SHIPBUILDING - ESAB Česká · PDF fileThe creation of this article was promoted by...

T H E E S A B W E L D I N G A N D C U T T I N G J O U R N A L V O L . 5 8 N O . 1 2 0 0 3

SHIPBUILDING

Contents Vol. 58 No. 1 2003

Articles in Svetsaren may be reproduced without permission but with an acknowledgement to ESAB.

PublisherBertil Pekkari

EditorBen Altemühl

Editorial committeeBjörn Torstensson, Johnny Sundin, Johan Elvander, Lars-Erik Stridh, Lars-Göran Eriksson,

Dave Meyer, Tony Anderson, Peter Budai, Arnaud Paque, Klaus Blome

AddressSVETSAREN, ESAB AB, Marketing Communication

c/o P.O. Box 8086, 3503 RB Utrecht, The Netherlands

Internet addresshttp://www.esab.comE-mail: [email protected]

Lay-out: Duco Messie, printed in the Netherlands

THE ESAB WELDING AND CUTTING JOURNAL VOL. 58 NO.1 2003

Photo courtesy Stocznia SzczecinskaNowa, Poland. The Bow Sun, the world’slargest duplex chemical tanker. TheFCAW of a series of these tankers will becovered in the next issue of Svetsaren.

New developments within the AluminiumShipbuilding IndustryRecent developments in the construction offast patrol and transportation vessels for theUS military by Bollinger/Incat Inc., applyingthe latest higher strength varieties of the5083 aluminium marine alloy.

FSW – possibilities in ShipbuildingESAB LEGIO TM friction stir weldingmachines expand the scope of application ofaluminium in shipbuilding by providingaccurate welded components that requireminimal fit-up work, and by allowing the useof high strength aluminium grades that wereformerly regarded as un-weldable.

Efficient production of Stiffeners forShipbuildingESAB’s new IT-100 automatic T-beam weld-ing machine offers highly productive, auto-mated welding in an unmanned productionenvironment to shipbuilders and other fabri-cators with a need to produce beams.

ESAB Railtrack FW 1000 aids fabricationefficiency of the world’s largest aluminiumyachtMechanised MIG welding with RailtrackFW 1000 for horizontal and vertical buttwelds has greatly improved the welding effi-ciency in the building of the world’s largestalumium yacht at Royal Huisman, TheNetherlands.

How much heat can various steels andfiller metals withstand?The article reports on research into the maxi-mum heat input acceptable for high tensileconstruction steels.

ESAB Brazil provides BrasFELS shipyardwith extra FCAW productivity for offshorevessels The BrasFELS shipyard, in Angra dos Reis,Brazil, increases welding productivity withOK Tubrod 75 basic cored wire for low-tem-perature applications.

Secure downhill MAG welding of butt- andfillet welds with ESAB OK Tubrod 14.12The article reports on highly productivedownhill welding procedures used by Germanshipyards for thin-walled applications usingOK Tubrod 14.12 metal-cored wire.

Thermal Bevelling TechniquesThe article discusses the thermal bevellingtechniques available from ESAB, highlightingseveral cutting processes and a variety ofplate edge preparation applications.

Stubends & SpatterShort news and product introductions.

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The creation of this article was promoted by currentactivities within the United States military, the extraor-dinary developments in aluminium shipbuilding thathave been taking place in Australia, and the creationof new high strength aluminium alloys, primarily inEurope, for the shipbuilding industry.

I was fortunate enough recently to visit Incat TasmaniaPty Ltd. (Shipbuilding) off the southeast coast ofAustralia. This manufacturer has over the years takenaluminium shipbuilding to exciting new levels. In 1977they launched their first high-speed catamaran, andtoday they are manufacturing the new generation of 98-metre (100 plus yards) wavepiercers that are being eval-uated by the United States military (see figure 1).Incat has constructed more than 50 vessels of varyinglengths. The company’s first passenger/vehicle ferry wasdelivered in 1990, a 74-metre Wave Piercing Catamaranwith a maximum deadweight capacity of 200 tonnes.

The more recent 98m Evolution 10B range has a dead-weight four times that amount. While Incat-built ferriesinitially revolutionized transport links around theUnited Kingdom, today its ships operate in North andSouth America, Australasia, the Mediterranean, andthroughout greater Europe. Incat’s extensive shipbuild-ing activity is conducted from a modern facility withover 32,000 m2 under cover, located at Hobart’s Princeof Wales Bay Tasmania.

Aluminium Welded Ships Within The UnitedStates Military. In response to great interest from the US military inhigh-speed craft, a strategic alliance has been formedbetween Incat, the premier builder of the world’s fastestvehicle/passenger ferries, and Bollinger, a provenbuilder of a variety of high speed, reliable and efficientpatrol boats for the US Navy and Coast Guard.

Svetsaren no. 1 • 2003 • 3

By Tony Anderson - Technical Services Manager - AlcoTec Wire Corporation

The article describes recent developments in the construction of fast patrol andtransportation vessels for the US military by Bollinger/Incat Inc., applying the latesthigher strength varieties of the 5083 aluminium marine alloy. The section on weld-ability addresses the open-end questions that surround these very new alloys.

New developments within theAluminium Shipbuilding Industry

Figure 1. The Spearhead - new generation of 98-metre wavepiercers

The US government has awarded Bollinger/Incat USAthe charter for a High Speed Craft (HSC) for a multi-service program operated by various arms of the USmilitary. The HSC Vessel, now known as Joint VentureHSV-X1, is being used for evaluation and demonstra-tion trials in order to assess the usefulness of such tech-nology in US military and Coast Guard applications.Another charter, the USAV TSV-1X Spearhead is the USArmy’s first Theater Support Vessel (TSV) and is part ofthe Advanced Concept Technology Demonstrator(ACTD) program by the Office of the Secretary ofDefense and the US Army. TSVs promise to change theway the US Army gets to the fight by allowing person-nel to quickly deliver intact packages of combat-readysoldiers and leaders with their equipment and supplies.

Another order, from Military Sealift Command,Washington, D.C., calls for the lease of a 98m craftfrom Bollinger/Incat USA, LLC, Lockport, La., tosupport US Navy Mine Warfare Command. The shipwill be capable of maintaining an average speed of 35knots or greater, loaded with 500 short tons, consistingof 350 personnel and military equipment, have a mini-mum operating range of 1100 nautical miles at 35knots, and a minimum transit range of 4000 nauticalmiles at an average speed of 20 knots. The craft will becapable of 24-hour operations at slow speeds (3-10knots) for small boat and helicopter operations.

New Developments in High StrengthAluminium Alloys for Marine ApplicationsUntil fairly recently, the most popular base materialused for aluminium shipbuilding, 5083, has had very lit-tle rivalry from other alloys. The 5083 base alloy wasfirst registered with the Aluminium Association in 1954,and while often referred to as a marine aluminium alloy,has been used for many applications other than ship-building. The popularity of the 5083 alloy within theshipbuilding industry has been largely based on its avail-ability and also its ability to provide an aluminium alloywith excellent strength, corrosion resistance, formabili-ty and weldability characteristics. Other lower strengthalloys, such as 5052 and 5086, have been used for themanufacture of usually smaller, lower stressed and typi-cally inland lake boats, but 5083 has been predominantin the manufacture of ocean-going vessels.

In recent years, progress has been achieved by alu-minium producers in the development of improvedaluminium alloys specifically targeted at the shipbuild-ing industry. In 1995 the aluminium manufacturer,Pechiney of France, registered the aluminium alloy5383 and promoted this material to the shipbuildingindustry as having improvements over the 5083 alloy.These improvements provided potential for significantweight savings in the design of aluminium vessels andincluded a minimum of 15% increase in the post-weld

4 • Svetsaren no. 1 • 2003

Figure 2. GMAW being used on high strength large aluminium structural components atIncat’s Shipyard in Australia

yield strength, improvements in corrosion propertiesand a 10% increase in fatigue strength. These develop-ments, coupled with formability, bending, cutting, andweldability characteristics, at least equal to that of5083, made the 5383 alloy very attractive to designersand manufacturers who were pushing the limits to pro-duce bigger and faster aluminium ships.

More recently in 1999, the aluminium manufacturer,Corus Aluminium Walzprodukte GmbH in Koblenz(Germany), registered the aluminium base alloy 5059(Alustar) with the American Aluminium Association.This alloy was also developed as an advanced materialfor the shipbuilding industry providing significantimprovements in strength over the traditional 5083alloy. The 5059 alloy is promoted by Corus as provid-ing improvements in minimum mechanical propertiesover alloy 5083. These improvements are referenced asbeing a 26% increase in yield strength before weldingand a 28% increase in yield strength (with respect toalloy 5083) after welding of H321/H116 temper platesof the AA5059 (Alustar alloy).

Welding the New Aluminium AlloysThe welding procedures used for these high strengthalloys are very similar to the procedures used whenwelding the more traditional 5083 base alloys. The5183 filler alloy and the 5556 filler alloy are both suit-able for welding 5383 and 5059 base alloys. Thesealloys are predominantly welded with the GMAWprocess using both pure argon and a mixture ofargon/helium shielding gas. The addition of helium ofup to 75% is not uncommon and is useful when weld-ing thicker sections. The helium content provides high-er heat during the welding operations, which assists incombating the excessive heat sink when welding thickplate. The extra heat associated with the helium shield-ing gas also helps to reduce porosity levels. This is veryuseful when welding the more critical joints such ashull plates that are often subjected to radiographicinspection.

The design strength of these alloys are available fromthe material manufacturer, however, there wouldappear to be little as-welded strength values incorpo-rated in current welding specifications. Certainly theserelatively new base alloys are not listed materials with-in the AWS D1.2 Structural Welding Code –Aluminium, and consequently no minimum tensilestrength requirements are included in this code. If thismaterial continues to be used for welded structures,there will be a need to address this situation by estab-lishing appropriate tensile strength values and toinclude them in the appropriate welding codes.

Early testing on the 5059 (Alustar) base alloy indicat-ed that problems could be encountered relating to theweld metal being capable of obtaining the minimumtensile strength of the base material heat affectedzone. One method used to improve the weld tensilestrength was to increase the amount of alloying ele-ments drawn from the plate material into the weld.This was assisted by the use of helium additions to theshielding gas, which produces a broader penetrationprofile that incorporates more of the base material.The use of 5556 filler alloy rather than the 5183 fillercan also help to increase the strength of the depositedweld material.

Obviously these high performance vessels require highquality welding. The training of welders, developmentof appropriate welding procedures, and implementa-tion of suitable testing techniques are essential in pro-ducing such a high performance product.

The futureWith the increasing demand to create larger and fasterships, particularly for military service, and the develop-ment of new improved, high-performance aluminiumbase materials, it is apparent that aluminium weldinghas acquired an interesting and important place withinthe shipbuilding industry. Also, with the pending intro-duction of this unique technology into the UnitedStates, it is important that designers, manufacturers,and particularly welders and welding engineers are ade-quately trained and familiar with this new technology.


About The Author:

Tony Anderson is Technical Services Manager ofAlcoTec Wire Corporation, MI, USA, Chairman ofthe Aluminium Association Technical AdvisoryCommittee on Welding and Joining, Chairman ofthe American Welding Society (AWS) Committeefor D10.7 Gas Shielded Arc Welding of AluminiumPipe, Chairman of the AWS D8.14 Committee forAutomotive and Light Truck Components WeldQuality - Aluminium Arc Welding and ViceChairman of the AWS Committee for D1.2Structural Welding Code - Aluminium.

Assembly work has never been easierImagine if a large catamaran could be constructedfrom building blocks, just like a toy boat. All pieceswould fit perfectly to each other and dimensional accu-racy and changes could be mastered to full degree.Friction Stir Welding takes the first step towards suchassembly work in shipbuilding. Due to the low heat-input during joining and resulting very low residualstresses, the welded components are accurate and min-imal fit-up work is needed. The resulting savings inboth time and money are obvious. Since this createscompetitive advantage to the users of FSW pre-fabri-cates, documented information of actual savings is notvery often reported. However, Midling et. al. 2000,gives an idea of the possibilities gained by friction stirwelded pre-fabricated panels from a panel producerspoint of view:

• Industrial production with a high degree of completion.• Extended level of repeatability ensuring uniform

level of performance, quality and narrow tolerances.• The flexible production equipment and capacity allows

customer built solutions with reliability of delivery.

• The completed panel units are inspected andapproved at present by classification authorities suchas DNV, RINA and Germanischer Lloyds.

• The high level of straightness of the panels ensure easyassembly at yard, which means less manual welding.

• Supplementary work for the customer, such as lessneed for floor levelling and preparation for floor cov-erings also is a major cost saving with FSW panels.

What is gained after the welding?One of the most attractive features of friction stirwelded products is that they are ready-to-use. No timeconsuming post-weld treatment such as grinding, pol-ishing or straightening is needed. With proper designthe elements are ready-to-use directly after welding.However, it is important to keep in mind that designswhich are made for MIG or TIG welding, are not nec-essarily suitable for friction stir welding. The limitingfactor often being the relatively high down-force need-ed when friction stir welding. A proper support in aform of backing bar or design change are often needed(Figure 2). Once done, repeatability reaches levels pre-viously not experienced in welding.


By: Kari Lahti, ESAB AB Automation, Gothenburg, Sweden

Aluminium is increasingly being recognised as an alternative, weight-savingconstruction material in shipbuilding. Friction Stir Welding expands the scopeof application of this material by providing accurate welded components thatrequire minimal fit-up work, and by allowing the use of high strength aluminiumgrades that were formerly regarded as un-weldable. ESAB LEGIO™ modularfriction stir welding machines bring this new welding process within reach atmoderate investment costs. Here we discuss the main benefits of friction stirwelded aluminium components in ship structures.

FSW – possibilities in Shipbuilding

Figure 1. Friction stir welded, straight panels under inspectionat ESAB FSW Center of Excellence in Sweden.

Figure 2. Designs suitable for friction stir welding of 2-skinprofiles in aluminium. Illustration: ESAB

When producing large surfaces like walls or floors,besides the straightness of the panels, also the resultingreflections are an important and expensive issue toconsider. A lot of time is spent polishing and "making-up" surfaces which are architecturally visible. In FSWprefabricated panels, the reflections are merely causedby the surface appearance of the aluminium plates andprofiles in the as-delivered state, not by the reflectionscaused by welding heat input.

Why use aluminium instead of steel?One excuse of not using aluminium has always been"that it is not as strong as steel." True – and not true. It,of course, depends also on the alloy to be used, and sur-prisingly enough, there are aluminium alloys which areas strong or even stronger than steels. For example theso called "ALUSTAR" has yield and tensile strenghtscomparable to low-alloyed steel S235. AlCu4SiMg(AA2014) – an alloy typically used in aerospace appli-cations –has siginficantly higher strength than alloys in5xxx- and 6xxx series which are typically used in ship-building. Some of these alloys just have not been usedin shipbuilding before, due to their poor weldability!

With friction stir welding, some of these barriers can beovercome – just imagine, for example, using strongalloy AA7021 for making aluminium floor panels eventhinner, and gain weight savings by "thinking different-ly". In Figure 3 the weldability of various aluminiumalloys is shown as a reminder. The typical alloys used inshipbuilding are from 5xxx –series due to their goodcorrosion resistance, or from 6xxx –series due to thestrength. A dissimilar combination between these twoalloys is of course also possible (Larsson et. al. 2000).

An easy way to make small-scale pre-fabri-cated panels or componentsFigure 4 gives an idea of relatively easy implementationof FSW in shipbuilding. ESAB’s new LEGIO™ con-cept is ideal for fabrication of small batches of frictionstir welded panels. The equipment is placed on theworkshop right next to the asembly of the shiphull. Thepicture is from Estaleiros Navais do Mondego S.A.Shipyard in Portugal. Even small batches can effec-tively be welded on-site.

The LEGIO™ concept represents a modular, moderndesign available for friction stir welding. A series ofstandardised welding machines puts FSW at every-one’s reach. Welds with highest quality are producedeven in small batches. Table 1 summarises the range ofmachines available in the LEGIO™ system. A size "3"should cover the needs of most shipyards.


Figure 3. Weldability of different aluminium alloys. ” TWI.

Figure 4. FSW LEGIO™ 3UT installed next to shiphullproduction line at Estaleiros Navais do Mondego S.A.Shipyard in Portugal.

Figure 5. Hat profiles stacked for shipping. Definitely nostraightening needed after the welding process. Photo: Hydro Aluminium.


Table 1. The family picture of the new modular LEGIO™ family for easy implementation of friction stir welding.

Size Vertical Spindle AA 6000 AA 5000 AA 2000 CUdownforce effect AA 7000 (oxygen free)

FSW 1 6 kN 3 kW 3 mm 2 mm 1.5 mm 0.8 mmFSW 2 12.5 kN 5.5 kW 5 mm 3.5 mm 2.5 mm 1.5 mmFSW 3 25 kN 11 kW 10 mm 7 mm 5 mm 3 mmFSW 4 60 kN 18 kW 18 mm 10 mm 9 mm 7 mmFSW 5 100 kN 22 kW 35 mm 20 mm 18 mm 12 mmFSW 6 150 kN 45 kW 60 mm 40 mm 35 mm 25 mmFSW 7 200 kN 90 kW 100 mm 75 mm 70 mm 40 mm

How to proceed?Friction Stir Welding is much easier to implement thanmost other welding processes. The welding operatordoes not need any special skills, since the parametersare repeatable and high quality is easily achieved timeafter time. You don’t need to be big and powerful toinvest in Friction Stir Welding – the modular way. Itmay, however, make You big and powerful by shorten-ing cycle times and improving the quality of Yourproducts. Just dare to do it!

References:Larsson H., Karlsson L., Svensson L-E, 2000. FrictionStir Welding of AA5083 and AA6082 Aluminium. In:Svetsaren 2(2000). 5 pp.Midling O.T., Kvåle, J.S. 1999. Industrialisation of thefriction stir welding technology in panels productionfor the maritime sector. In: The 1st InternationalSymposium on Friction Stir Welding. Thousand Oaks,CA, USA 14-16 June. 7 pp.

About The Author:

Mr. Kari Erik Lahti graduated from HelsinkiUniversity of Technology, Finland, 1994 with aM.Sc. degree in welding technology. After workingas a research scientist in the field of welding metall-lurgy, he joined Oy ESAB in Finland 1997 and star-ted as product manager for welding automation.In 1998 Kari Lahti finalised his Ph.D. in "nominalstress range fatigue of stainless steel fillet welds"Since 2002 he has been working at ESAB ABGöteborg, Sweden, currently as marketing managerfor advanced engineering products.

1. Introduction ESAB has marketed and distributed robust, manual T-beam welding equipment for many years, equipmentdesign generally following market demand. Although,a typical T-beam welder was partly mechanized, all set-tings of the welding machine had to be carried outmanually by an operator due to its prescribed weldingprocedures. Therefore, the design and control technol-ogy of such machines is fairly simple, relying heavily onhighly skilled operators to produce parts of consistent-ly high quality.

Many companies, especially shipyards, are experienc-ing increasing competition from many other worldwideoperating enterprises. To survive, in an often toughand continuously shrinking market, shipyards mustnow find new ways to increase their internal produc-tivity. One way to increase productivity is to increasefactory automation. Production equipment whosedesign provides the factory with a higher degree ofautomation also increases efficiency and quality levels.

For example, modern control technology makes it alsopossible to schedule “tighter” production runs by pre-setting the production equipment with instruction setsimportant for unmanned operation. The control sys-tem can also be connected to an internal MRP systemfor even more efficient production efficiency.

As suppliers of state-of-the-art welding equipment,ESAB has seen an increasing demand for more sophis-ticated production systems equipped with the latest con-trol technology. To meet this demand, ESAB has devel-oped an automated T-beam welding system, which canbe used in an unmanned production environment.

2. Equipment for T-beam ProductionSituated upstream and downstream of the T-beam weld-ing machine there are a number of material handlingequipment cells, including:

• In-feed conveyor usually situated after a cuttingmachine.

• Grinding and shot-blasting equipment.• Web raising station.• Web alignment station upstream to the T-beam

welder.• T-beam welder with peripheral equipment.• Out-feed conveyor with raising/lowering capability. • Cooling bed.• Straightening equipment.• Shot-blasting equipment.• Priming booth. • Cutting equipment for notches and holes.• Centralized control system.

Modern production equipment needs to be flexible towork efficiently in an automated environment. It istherefore of great importance to be able to integratethese work cells into a centralized computer system,which is then able to communicate with modern infor-mation systems (e.g. MRP).

2.1 In-feed conveyorThe beam welding system becomes more productive ifthe beam is supported and conveyed through themachine in a very precise manner. In other words, theprecision of the in-feed conveyor will directly affectthe precision of the finished beam (Figure 1).A raising station situated upstream of the in-feed con-veyor will place the web in the middle of the flange and


By Herbert Kaufmann, ESAB AB, Welding Automation

ESAB’s new IT-100 automatic T-beam welding machine offers highly pro-ductive, automated welding in an unmanned production environment toshipbuilders and other fabricators with a need to produce beams.Optimum welding speed, beyond 1m/min., is provided by double-sidedtandem submerged arc heads. Web and flange are automatically longi-tudinally centered in the in-feed conveyor, whereas on-line straighteningof the beams is provided by inductive heating, avoiding time-consumingpost-weld straightening procedures.

Efficient production of Stiffeners forShipbuilding

then feed it into the in-feed conveyor. The beam thenstops after it passes through the first set of the verticalfeed rollers. The flange width will be measured and itsdimension will be transferred to the controller of thebeam welder.

Even if the measured flange width differs along thebeam length, centering the web exactly on the centerof the flange now becomes easier. If the measureddimension of the flange is out of tolerance an alarmwill sound and then the operator can decide if the tar-get beam should be welded or not.

Before reaching the T-beam welder, longitudinal cen-tering adjustment of the web and flange has been com-pleted after the beam has passed through all three pairsof rollers. T-beams with a positive or negative value canbe produced even though the offset defaults to “zero”.

The traverse speed of the in-feed conveyor is synchro-nized with the beam welding speed, which is controlledby the T-beam welder.

2.2 T-beam welderThe newly developed IT-100 Automatic T-beam weld-ing machine has been optimized for the production ofsymmetrical T-beams. With small modifications, themachine will weld other types of profiles and beams(Figure 2).

All pre-set values for the T-beam welder, for example,of the beam sizes and associated weld parameters canbe made by the operator or obtained from a customer’sproduction planning system. It is therefore possible torun the T-beam line with mixed production schedulesof varying sizes of T-beams, without interrupting theongoing production.

Several features of the new IT-100 Automatic areworth mentioning. With the IT-100 Automatic, beamscan now be welded without having to tack weld theweb and flanges. Another important improvement isthe automatic centering feature which always positionsthe web into the center of the flange even if the flangewidth varies. Also, welding 5 mm from the start andthe end of the T-beam guarantees efficient utilizationof T-beam material for the finished beam.

The system’s main controller is an Allan Bradley PLCtype Control Logic 5550. Internal communication isvia a DeviceNet bus. All external devices are linked tothe controller by an Ethernet bus system. The con-troller also uses a modem for remote supervision, tomake programme alterations, and to become assess-able for service diagnostics from the outside. Installa-tion and specific production parameters (weldingparameters and work piece dimensions) can beentered from the operators panel (Panel View 600).The operator can protect all settings with passwords.

The controller is also equipped with a built-in qualitymonitoring system. Parameters such as axis position,weld speed, voltage and current deviations are contin-uously monitored. Alarms will sound if parameters areoutside predetermined limits.

By tracking the consumption of consumables (wire andflux) the IT-100 Automatic will generate an alarm ingood time before new wire or flux needs to be loaded.


Figure 1. Infeed conveyor, front view.

Technical data:Length of infeed conveyor 6000 mmHeight of conveyor 720 mmWeight 6 tonsNo of flange/web rollers totally 6 (3 pairs of rollers)Rapid speed max. 16 m/min

Figure 2. ESAB’s T-beam welder IT-100 Automatic.

Technical DataWidth of Flange 102 – 600mmThickness of flange 10 – 41mmHeight of Web 150 – 915mmThickness of Web plate 6 – 25mm

2.3 Platform To save space all essential components have been placedon a platform located over the T-beam welders and partsof the in-feed conveyors. The corresponding span isapproximately two parallel T-beam lines (10 x 8 Meters)(Figure 3).

Essential components include control cabinets, a fluxfeeding system, and the hydraulic power unit and cool-ing units. Additional space is also available on thisplatform for storing flux and wire. All cables includingmain power connections are installed in cable traysunderneath the platform. Fences surround and guardthe platform area which is accessible only through twosets of stairs.

3 Beam straightening methodsAnother important feature in ESAB’s new T-beamwelding line is the ability to produce straight T-beamswith a high degree of precision and repeatability with-out utilizing a “post-weld” straightening procedure.Any necessary straightening process is done during thewelding phase and, therefore, subsequent manualstraightening procedures are unnecessary.Due to the heat input from the welding process, thefinished beam will have a certain positive camber(bow). Without ESAB’s straightening process a typicalcamber for a 16m long beam would be between 60 and100mm, depending on the amount of heat input duringthe welding process. Corrective straightening opera-tions afterwards will most likely adversely affect thebeam’s accuracy and straightness and possibly intro-duce other residual stresses in the beam.Cutting notches or holes into the beam after thestraightening process will affect the straightness of thebeam, again because of the release of some of theremaining stress in the beam section.

There are different production methods used to pro-duce straight beams. In the following section there arefour different straightening methods discussed.

3.1 Mechanical Flange straightening• Manual operation requiring a special machine.• Must be done by skilled operators. • Time consuming process.• Cannot be done during welding.• Risk of buckling distortion in the web.• Many types of distortion phenomena can be corrected.

3.2 Manual Flame straightening• Difficult to achieve high accuracy.• Time consuming process.• Use of water after welding causes corrosion prob-

lems in subsequent operations.• Must be done by skilled operators. • Many types of distortion phenomena can be cor-

rected.

3.3 Flame straightening with Propane burnersmounted to the T-beam welder (Figure 4)• Heated simultaneously during welding.• Difficulty predicting heat input.• Manual setting of heat input.• Poor repeatability.• Distortion in only one dimension can be corrected

(Camber).

3.4 Induction line heating straighteningBoth mechanical and thermal straightening techniquesare used to straighten beams subjected to plate shrink-age. Mechanical straightening requires large, expen-sive machines, which produce process “wrinkles”. Aswith thermal straightening, this technique adds anoth-er step to the beam production line.

Thermal straightening requires that the opposite(upper) side of the beam is heated – which laterinduces a compensating shrinkage. This is supposed tocompensate for the initial shrinkage induced duringthe welding process mentioned above and can be donewith Propane burner heating (see 3.3). The use of


Figure 3. Platform for storage of peripheral equipment.

Figure 4. ESAB’s T-beam welder IT258 with Propane torchheating/straightening.


induction heating equipment (Figure 5 + 6) offers sev-eral advantages:

• The concentrated heating produces a higherstraightening effect.

• Less risk of overheating the surface.• No noise.• Direct heating of the beam produces less heating of

the environment.• No toxic fumes.• Heat input is controlled.• Good temperature control.• Excellent repeatability.• Heat input can be set automatically

(programmable).

Induction heating is easy to adapt to an existing line.The required power for an induction heating systemfor larger T-beam production is approximately 60 to100 kW (EFD:s Minac 60 or 100 Dual system). The useof a Dual system (with two coils) is recommendedwhere one heating coil is used simultaneously on eachside of the Web.

By balancing the power input at Curie temperature,this system can be, “self-regulating”. The rapid heatingallows the thermal straightening to be done at the sametime as the welding providing a one-step productionprocedure. This is very cost effective due to substantialreduction in manpower and energy consumption.

When an alternating current flows through a coil, eddycurrents are induced in a metal object placed inside thecoil. Heat is developed where these eddy current flows.

On the other side of the T-beam an identical inductioncoil with guide rollers heats the hub.

4. Welding Process The IT-100 submerged-arc welding (SAW) configura-tion uses two single wires (DC+ AC) on each side ofthe web (Figure 7). The torch arrangement uses a lead-ing DC wire and a trailing AC wire. Offset between thewires is 12 mm. Power sources include the LAF 1250and TAF 1250. The welding controller is an AllanBradley PLC type Control Logic 5550

4.1 Welding EquipmentThe power sources proposed for this application arethe LAF 1250 DC power source and the TAF 1250 AC(square wave) power source.The welding system includes ESAB’s well-proven andreliable A6 components. Each of the welding torchescan be adjusted in three dimensions using slides andscales for accurate set-up. Wire drums (365 kg) areplaced on the platform above the beam weldingmachine. All wire feeders and wire straightening set-tings are also equipped with scales for easy adjustmentafter changing wire.

Figure 5. Induction heating principle.

Figure 7. DC-AC Torch arrangement in ESAB`s T- beam welder.

Figure 6. Induction coil with guide rollers during heating forstraightening of T-beams.

4.2 High speed SAW weldingWeld undercuts and arc blow due to welding at highercurrents are often the limiting factor for weldingspeed. In most situations multiple wires allow elonga-tion of the arc heat source to enable faster weldingwithout undercuts. To avoid or reduce arc blow, thebest solution is a tandem welding arrangement using aleading DC and a trailing AC torch.Weld speeds above 1 m/min can be easily achieved. Forhigh speed quality welding, it is also important to weldon clean plates free of mill scale and rust. Shot blastingor grinding of all original parts is essential (Figure 8).

5. Theoretical analysis of the distortion afterwelding a symmetrical T-beam The intense heat input from the welding process andthe molten steel, which is deposited into the joint, con-tribute to thermal expansion and contraction of theheated parts. Also residual stresses released in therolled and raw-cut material will have some influence onthe final shape of the beam.If the welding is done on only one side of the web theplate will bend upwards and sideways (sweep and cam-ber). If two welds are done simultaneously, one on eachside of the web, the beam tends only to exhibit beam-camber due to the shrinkage produced after welding.

Distortion can be minimized in symmetrical designs byapplying the heat into the material in a symmetricalmanner. The remaining distortion on the final part canrarely be tolerated in subsequent assemblies and mustbe eliminated with thermal or mechanical methods(see part 3 above).

5.1 Type of distortion in symmetrical T-beams:Camber:Bending distortion produced by longitudinal shrinkageupwards. Can be neutralized by applying similar heatinput as during the welding process into the upper part(above the neutral axis) of the T-beam.

There are different methods to calculate the size of thecamber. With modern CAD systems, mathematicaland thermal problems can be modeled easily. Thebiggest challenge is to determine the heat transfer andthe associated distribution in the beam that is neededas input for the calculation. Traditional methods ofdetermining the size of the camber use establishedbeam bending theory (within the elastic range of dis-tortion) where the beam is exposed to compressiveforces and torque on each end of the beam:

(1) δ = M x L2 / 8 x E x L = PW x b x I2 / 8 x E I

Whereδ = Camber in mm.PW = Shrinking force in N.L = length of beam in mm.E = modulus of elasticity in N/mm2.

I = moment of inertia in N/mm4.

b = distance from flange to neutral axis.

Shrinking force “Pm” per mm2 for different weldingmethods has been determined by Malisius (see refer-ences below). Typical shrinking forces for fillet weldsare 6300 N/mm2

With this formula, an approximate camber value can beeasily calculated. For a beam web size, flange size, andtotal length of 475 x 13mm, 125 x 25mm, and 16m,respectively, a resultant camber of 53mm is calculatedassuming a fillet weld on each side (leg length =8mm).

The result in this case seems to be too small comparedwith empirical data found in the field. The differencecan perhaps be explained by considering additionalforces associated with the shrinking effect of theflange. One effect could be attributed to the tempera-ture difference between the web and the flange meas-ured at the welding site. The temperature differenceseems to be the reason why the flange (but not theweb) length increases by δ l during welding. The heatwill enter into the flange much faster than the Webbecause the cross sectional area of the flange is muchsmaller than the web’s.


Figure 8. Cross section of welded T-beam.

I

δ

δ ≤ 0.3 mm/m

Figure 10. Elongation of flange during welding

Pax Pax

δ I

(2) δ l = δT x α x l

if δT = 30 degrees, α =11,7 x 10E-7 and l=16m then is δ l= 5.3mm

Shrinking force Pax which will reduce the beam lengthby δ l

(3) Pax = A x δ l/l x E (Hookes law)

If A= area of flange 125 x 25mm =3125mm2 and E =210 MN/m2. With the known figures the shrinking forcePax= 220000 NFigure 9. Camber.


However, it is difficult to determine the temperaturedifference δT. An average temperature must be usedas the temperature distribution in the flange dependson the mass ratio between the web and the flange.

The total shrinking force becomes:P = Pw + Pax = 403200 + 220000 = 623 kNBy using formula (1) again the total camber ∆ nowbecomes 82 mm. This is more in line with the empiricalresults.

Sweep:Bending distortion due to longitudinal sidewaysshrinkage caused by unsymmetrical welding heat input(e.g. different weld parameters in fillet welds or biglongitudinal offset between torches).The sideways sweep phenomenon can be calculated ina similar way, but its associated shrinking force must bedetermined experimentally. It is important to limit un-symmetrical heat input to the beam and also to makesure that the web is centered and perpendicular to theflange (Figure 11).

Perpendicularity between web and Flange:Perpendicularity deviations are usually caused byusing different weld parameters for fillet welds or frombig longitudinal offset between torches (Figure 12).

Angular Change (of flange) in fillet weld:Caused by different temperatures between top andbottom of flange. Bending distortion caused by trans-versal shrinkage sideways and upwards (Figure 13).Release of Residual stresses from previous heat treat-ment and rolling operations:Residual stresses contained in the raw sheet materialdue to milling and cutting operations will have anunpredictable impact on the straightness of the fin-ished part. It will particularly influence the repeatabil-ity of the straightening process.

s ± 0.9mm/m

Figure 11. Sweep.

d= ± 1.5 / 100 x b

Figure 12. Perpendicularity.

Figure 13. Angular Change.

Reason

Bending distortion by longitudinal shrinkage upwards.

Bending distortion by longitudinal shrinkage upwards.Unsymmetrical heat input from the welding process (different weld parameters in fillet welds. Big longitudinaloffset between torches).

Different weld parameters in fillet welds, big longitudinaloffset between torches.

Caused by different temperatures between top and bot-tom of flange. Bending distortion by transversal shrinkagesideways and upwards.

Releasing of residual stresses from earlier heat treatmentand rolling operations of raw material.

Measure

Can be neutralized by applying heat ontop of the T-beam (see point 3 above).

Perpendicularity (see below) needs to becorrected.Change setting of weld parameters andreduce offset of torches.

Change weld parameters and reducetorch offset.

Use mechanical "pull down" straighteningfeature of T-beam welder.

Use heat treated material, use cuttingprocess with lower heat input.

Type of distortion

Camber

Sweep

Perpendicularity(between Web andFlange)

Angular change (of flange)

Release of residualstresses

c ± 0.5 x b/100

Summary of all types of beam distortions

5.2 Straightening by line-heatingBy applying heat to the top of the beam during thewelding process it is possible to produce straight beams(see point 3.4). The theory behind this is to achieve abalance between the heat applied by the weldingprocess (below the neutral axis of the T-beam) and bythe heat applied by the proposed straightening process(above the neutral axis of the T-beam).

The best way to predict the required heat input of thestraightening process is to create an empirical tablewith data derived from full-scale experiments. Thefinal condition of the beam is usually obtained afterapproximately 1 hour after welding was finished.Theoretical calculations require a lot more data. Heatdistribution in a beam can be measured and then beused as part of these calculations. The heat distributionin a T-beam (same size as used in above calculations) isshown in figure 14.

A beam is free from distortion (camber) when the heatinput from the welding process can exactly be balancedby the heat input from the induction heater:

∑ heat input above Neutral Axis = ∑ heat input belowNeutral Axis

or expressed by formula:

(4) ∫w Xb x �(xweldtemp) dx = ∫H Xa x �(xheating) dx(Temperature x length to neutral axis)

WhereXb = distance to neutral axis (welding).�(xweldtemp) = heat distribution in the T-beam from

welding process.Xa = distance to neutral axis (heating).�(xheating) = heat distribution in the T-beam from

heating process.

By solving the integrals in formula and by using theheat distribution as shown in the figure the heat inputon both sides of the neutral axis must be equal.

6 References1996, Andersen N. High deposition welding with sub-arc – forgotten andoverlooked potential, Svetsaren Vol. 51, No.3, p. 12 –19.

1987 Conner L. P.Welding Technology, Welding Handbook, EighthEdition, Vol. 1, American Welding Society, p. 241 – 264.

1989, ESABKrympning, Deformationer, Spändinger. ESAB´s handbågsbibilitek 9 (in danish).

1991, Gustavsson J.Automatic production machinery for the fabricationof welded steel beams and profiles. Svetsaren Vol. 45No.2, p. 46-30.

1977 Malisius R.Schrumpfungen, Spannungen und Risse beimSchweissen 4. Auflage, 154 p, DVS Verlag, ISBN 3-87155-785-4.

1996, Persson M.Manufacture of welded beams. Svetsaren Vol. 51,No.3, p. 20-21.


Figure 14. Heat distribution in a T-beam during the weldingoperation.

About The Author:

Herbert Kaufmann, M. El. Sc. and M. Mech. Sc., joi-ned ESAB in 1988 as Technical Director at ESABAutomation Inc., USA. He is currently working asProject Manager within the EngineeringDepartment of ESAB Welding Equipment in LaxåSweden.


Translation of an article first published in Laswijzer, the customer magazine of ESAB The Netherlands.

By: Guus Schornagel, ESAB, The Netherlands.

Improved welding efficiency has been a major consideration for Dutch boatbuilder, RoyalHuisman, in the planning, design and construction of The Athena – the world’s largestaluminium yacht. This has been achieved by implementing mechanised MIG welding withRailtrack FW 1000 for horizontal and vertical butt welds on the yacht’s hull.

ESAB Railtrack FW 1000 aidsfabrication efficiency of theworld’s largest aluminium yacht

If you can dream it, we can build it. The making of a sailing yacht is an intensesynergy between art and science,between heart and hand: It is a strikingharmony between rough sketches onfoolscap and crisp printouts on mylar; atranslation of vague mental conceptioninto hard-edged lofting; a focusing of dif-fuse artisy into plasma-sharp cutting; thelanding of euphoric flights of imaginationby a micro chip's swift calculation.(Excerpted from "Juliet: The Creation of aMasterpiece" text by Jack A. Somer andphotographs by Peter Neumann).

Royal HuismanThe history of this Dutch yard dates back to 1884 whenthe Huisman family started to build many differenttypes of wooden boat. From 1954, all boats were fabri-cated in steel and, in 1964, the yard was among the firstin Europe to construct boats in aluminium. In the fol-lowing years, Huisman expanded this specialisation tothe point where, today, all their products are madefrom aluminium. The company’s in-house motto is "if you can dream it, we can build it."

The yard employs some 325 personnel, including thoseof Rondal, a supplier of masts, deck fittings and winch-es. Huisman personnel work directly for the customerwhich results in a high degree of flexibility and effi-ciency during the build process. The yard has its ownadvanced composites department, painting halls, and

an advanced furniture workshop that produces inter-nal designs to satisfy the wishes of individual clients.Huisman is renowned for its global customer base. The legendary Flyer I and Flyer II, winners of theWhitbread Race around The World, with captainConnie van Rietschoten, are perhaps the most famousexamples of Huisman’s performance.

The AthenaOn November 22 in 1999, after a year of intensive prepa-ration and design, the contract was signed for the con-struction of the world’s largest three-master schooner -The Athena. With a total length of almost 90 meters, sheis the largest yacht ever to be constructed in aluminium.The Athena project came to life on the drawing board ofdesigners Pieter Beeldsnijder and Gerard Dijkstra andwill be completed in September 2004.


About the author

Guus Schornagel joined ESAB in 1966, and until hisretirement in 2001 he had various technical-commer-cial positions, among others as PR manager forESAB The Netherlands. Currently, he works as afreelance technical writer for Laswijzer, the customermagazine of ESAB The Netherlands.

Significant features of the vessel are:• total length: 90m• width: 12.20m• depth: 5.5m• three 60m masts• two 2000 HP Caterpillar engines• weight: 982 ton• total sails surface: 2474 m2

• crew: 21 persons

The hull, produced in Huisman’s indoor hall, took oneyear to construct. Hulls are usually constructed up-sidedown. However, the unusual dimensions of The Athenamade it necessary to build in the upright position.

The weldingThe construction of a ship hull requires an enormousamount of welding. Traditionally, manual MIG weldingwas applied for horizontal and vertical butt joints in thehull. However, the scale of this project made higherwelding efficiencies and economies very important.

In close cooperation with ESAB’s product specialist,Piet Lankhuyzen, the possibilities of using ESABRailtrac equipment were investigated.Demonstrations and tests were carried out at the yardand further production advice was offered by anotheryard, Barkmeyer in Stroobos, that had several years ofsatisfactory experience with Railtrack equipment.Royal Huisman finally opted for ESAB’s Railtrac FW1000 Flexi Weaver with a 30 meter long rail and vacu-um suction brackets. The thickness of the hull platesvaries between 10 and 15mm and the equipment isused for both horizontal as well as vertical joints. Thewelds are primarily built-up in three layers, one rootpass and two cap beads.

Production experienceHuisman’s production manager, Henk Petter, is verysatisfied with the results so far. He cites "reduced arctime, the consistent weld quality, the absence of lack offusion defects, and, very importantly, the fact that thework has become less strenuous for the welders" as themost appealing improvements.

"The welders have been involved right from the start",says Henk, "which facilitated the implementation andacceptance of the new technology. The close co-opera-tion between the yard and ESAB has played a crucialrole in this process."

Railtrac FW 1000• Suited for welding magnetic and non-magnetic

materials in all positions.• Quick fit-up and user friendly.• 5 programmable settings.• Calibrated settings in cm, mm and seconds.• Programmable function for crater fill-up.

• Instructive handbook for programming.• Flexible rail without rack made of standard aluminium

profile.• Rail can be lengthened or shortened as required.• Optional unit for torch angle adjustment.• Tilting weaving unit for fillet welds (optional).• Rotatable weaving unit for horizontal movements

on vertical slanting joints (optional).• Hovering head for mechanical height adjustment

(optional).• Remote control for parameter setting.

The cooling rate determines the propertiesThe mechanical properties of a welded joint signifi-cantly depend on the cooling rate of the joint, and thisin turn is influenced by the heat input (welding ener-gy), plate thickness and working temperature (inter-pass temperature). The most significant microstructurechanges from the viewpoint of the properties of theweld metal and the heat-affected zone take place dur-ing the cooling of the joint within the temperaturerange of 800-500ºC. It is usually the cooling time t8/5,i.e. the time required for this temperature range to bepassed, which is used to describe the cooling rate.

It is recognized that high heat input (kJ/cm, kJ/mm),i.e. a long cooling time t8/5 (s) weakens the mechanicalproperties of the joint - both its tensile strength andimpact toughness. Toughness is generally more sensi-tive than tensile strength to high heat inputs. Forexample, heat input is high when the welding speed(travel speed) is low, as shown in the equation:

Welding current x Arc voltageWelding energy =

Welding speed(arc energy)

6 x I (A) x U (V) E = (kJ/mm)

1000 x v (mm/min)

Heat input= thermal efficiency factor x welding energy (arc energy).

Q = k x E (kJ/mm)

Thermal efficiency factor (EN 1011-1): • Submerged arc welding: 1• MIG/MAG and MMA welding: 0.8

Figure 1 shows schematically the effect of cooling timeon the hardness and impact toughness of the heat-affected zone. Optimal properties will be obtained forthe joint when the cooling time is within range II.

Figure 1. Effect of cooling time on the hardness and theimpact toughness of the heat-affected zone of the weldedjoint.

When cooling time is short, i.e. when the weld coolsquickly (e.g. low heat input or considerable plate thick-ness), the hardness within the heat-affected zoneincreases greatly as does the tendency to hydrogencracking because of hardening. On the other hand, theimpact toughness properties are good, i.e. the transi-tion temperature is low. Likewise, if the cooling time isvery long, hardness will remain low but the impacttoughness properties will be impaired, i.e. the transi-tion temperature rises to higher temperatures and ten-sile strength may decrease.

Heat input to be restrictedTo ensure sufficient impact toughness in the weldedjoint, it is necessary to restrict the maximum heatinput. This need to restrict maximum heat input is somuch the greater, the more demanding is the particu-lar steel’s impact toughness (i.e. the lower the guaran-tee temperature of the impact toughness is), the high-er its strength class and the smaller its plate thickness.

When the issue is that of impact toughness requirementsat -40ºC or lower, for example when applying thickwelds in submerged arc welding applications, then theupper limit for heat input is of the order of 3-4 kJ/mm.


How much heat can various steels andfiller metals withstand?By Juha Lukkari, ESAB Oy, Helsinki, Finland and Olli Vähäkainu, Rautaruukki Steel, Raahe, Finland

The mechanical properties of welded joints and, in particular their quality in pro-duction welds, is amongst the most important considerations when developingwelding procedures. High heat input (welding energy), in particular, weakens thetoughness properties of welded joints.

I II III

Hardness

Transitiontemperature

Cooling time t8/5

High heat inputs cause powerful grain size growthwithin the overheated heat-affected zone, immediatelyadjacent to the fusion line. Moreover, this causes theformation of microstructures, within the heat-affectedzone, that are disadvantageous from the viewpoint ofductility; for example, grain-boundary ferrite, polygo-nal ferrite and side plate ferrite. Furthermore, impuri-ties (sulphur and phosphorus) segregate to the grainboundaries, which also impairs ductility. Similar char-acteristics also apply to the weld metal.

Rautaruukki is, possibly, the first, steel mill in theworld to have drawn up heat input graphs for its pro-duction steels. The graphs were based on the results ofextensive tests in which fine-grained steels were sub-jected to different heat inputs for welding. Impacttoughness was tested by studying different zones in thewelded joints.

The lower the heat input, the more passes have to bemade, and the lower, generally, is the deposition rate.This has the effect of diminishing the productivity ofwelding. The general aim is to use high heat inputs,which is restricted by the heat-input limits issued bythe steel mill on a particular steel grade. Rautaruukkihas published heat input restrictions on its steels in theform of welding energy or heat input graphs, e.g. in thebooklet Hitsaajan opas (Welding guide), Figure 2.

Restricting heat input can also be indicated by means ofcooling time t8/5. Rautaruukki presents the maximumallowable cooling times for various steel grades in thebooklet, Table 1. The booklet also sets out the instruc-tions for determining cooling times, which can be doneby calculation, or graphically by means of a nomogram.

Rautaruukki repeats researchSince the publication of the first heat input graphs, in1972, Rautaruukki has conducted many studies intothe effects of heat input - most recently in 2001-2002.On the basis of these tests, the heat input recommen-dations for the foremost Rautaruukki hot-rolled steelswill be reviewed and where necessary the instructionswill be reformulated. By applying the heat input rec-ommendations it will be possible to ensure maximumproductivity of welding joints along with the impacttoughness and tensile strength firmness requirementsimposed on joints.

The plate thicknesses used were 12mm (two-run welds,not reported in this shortened article), 20mm and40mm. Submerged arc welding, which readily enableshigh heat inputs, was the process applied. The heatinput in the tests varied between 20 and 80 kJ/cm.

The first group comprises conventional and commonlyused steels, fine-grained steel RAEX Multisteel (corresponds to EN 10025: S355J2G3 and S355K2G3)and the general structural steel S355J2G3 (EN 10025):

• Strength properties: ReH = min 355 N/mm2

(≤ 16mm) and min 345 N/mm2 (s≥16≤40mm), Rm= 490-630 N/mm2.

• Impact toughness (RAEX Multisteel): min 40 J/-20ºC.• Impact toughness (S355J2G3): min 27 J/-20ºC.


S355J2G3 (= Fe52D) 30 -20S355N 30 -20S355NL 20 -40S420N 25 -20S420NL 15 -40S355M 40 -20S355ML 30 -50S420M 35 -20S420ML 25 -50S460M 35 -20S460ML 25 -50S500M 35 -20S500ML 25 -50

Steel grade t8/5 TEN 1) 2)

(s) (ºC)

Table 1. Maximum values for cooling time t8/5 as issued forRautaruukki steels.

6.05.65,24.84.44.03.63.22.82.42.01.61.20.8

Heat Input (kJ/mm) EN 10025S355NS355J2G3

EN 10113-2S420N

S355NL

S420NL

Figure 2. Heat input limits for Rautaruukki steels when weld-ing butt joints.

10 20 30 40 50 60Plate thickness (mm)

1) Cooling time t8/5.2) Testing temperature for impact toughness.

The second group comprised thermo-mechanicallyrolled (TM) steels, whose ability to withstand highheat inputs is, as is well known, good:

• RAEX 420 M/ML (EN 10113-3: S420M/ML): • Strength properties: ReH= min 420 N/mm2 (≤ 16mm) and min 400 N/mm2

(s>16≤40 mm), Rm= 500-660 N/mm2.• Impact resistance (M): min 40 J/-20ºC.• Impact resistance (ML): min 27 J/-50ºC.

• RAEX 460 M/ML (EN 10113-3: S460 M/ML):• Strength properties: ReH= min 460 N/mm2

(≤ 16mm) and min 440 N/mm2 (s>16≤40 mm), Rm = 530-720 N/mm2.

• Impact toughness (M): min 40 J/-20ºC.• Impact toughness (ML): min 27 J/-50ºC.

• New markings: RAEX 420 ML= RAEX 420 ML OPTIM (EN 10113-3: S420 ML).

• New markings: RAEX 460 ML = RAEX 460 ML OPTIM (EN 10113-3: S460 ML).

The filler metals were the ESAB wire-flux combina-tions typically used with these steels, Table 2.

The wire-flux combination used with fine-grained steelRAEX Multisteel and the general structural steelS355J2G3 was the non-alloyed OK Autrod 12.22 +OK Flux 10.71 and for TM steels it was the nickel-alloyed OK Autrod 13.27 with flux OK Flux 10.62.This combination produces good impact toughness inmulti-run welding down to –60ºC.

Test plates were tested to determine their tensilestrength by means of a transverse tensile test and theirimpact toughness was examined along different zonesin the joint (weld metal, fusion line and heat-affectedzone: fusion line + 1 mm and fusion line + 5 mm).

The impact test results are presented in Tables 3-6, andthese results are dealt with in the following.

The results were good, some even surprisingly excellent.What else can one say when the entire joint withstandsa heat input of 80 kJ/cm and when the impact energypersists at 100-200 J at test temperature of –50ºC!

Impact toughness of 40mm jointThe results for 40 mm TM steel plates were extremelygood and they easily met the requirements of Tables 3and 4. The applied heat inputs were extremely high, 70kJ/cm and 80 kJ/cm. S420 M/ML and S460 M/ML wereable to easily withstand heat inputs as high as theseand the impact energy of the heat-affected zoneexceeds 100 J at the test temperature of –50ºC. Eventhe weld metal would appear to be able to withstandthis. In the case of steel S460 the value of the impactenergy of the weld metal also exceeded 100 J at –50ºC.

Also, steels RAEX Multisteel and S355J2G3 and theirweld metals were surprisingly able to withstand heatinputs as high as 70 kJ/cm when impact resistance wastested at –20 ºC, Tables 5 and 6. However, the safe limitis most probably much lower than this.

It should be borne in mind that the impact toughnessof the weld metal is also significantly affected by theweld structure (run sequence) and the reheating of fol-lowing runs, which may be manifested in the tables forwelds involving 45º-, half-V, and 60º-V grooves. In thecase of a weld having a different run sequence, theimpact energy value could be different, e.g. it could belower, even if the heat input were the same.

Impact toughness of a 20 mm jointThe heat input in welding TM steels was 55 kJ/cm.Steels and weld metals withstood such high heat inputsextremely well. Impact toughness was tested, at therequired test temperatures, down to –50 ºC, Table 3and 4.

When welding the steels RAEX Multisteel andS355J2G3 the heat input varied between 30 kJ/cm and55 kJ/cm. The cooling times become considerablylonger than when welding 40 mm plates even thoughthe heat input is considerably lower. The maximumheat inputs appear to be excessive from the point ofview of the weld metal, and the upper limit is perhapsaround 45 kJ/cm with the impact test temperaturebeing –20ºC, Tables 5 and 6.The same remarks concerning the run sequence applyin this case for impact properties of the weld metal asare mentioned for 40 mm plate.

Heat input and plate thicknessHeat input, alone, may be misleading. Heat inputshould always be considered together with plate thick-ness. These, together with the interpass temperature,specify the cooling rate of the weld.

The tables reveal, for example, that a heat input of 80kJ/cm with plate thickness of 40 mm gives a coolingtime t8/5 of 59 s. With plate thickness of 12mm, the cool-

OK Autrod 12.22 S2Si - OK Flux 10.71 - S A AB 1 67 AC H5 Wm: 12.22+10.71 S 38 4 AB S2Si - OK Autrod 13.27 S2Ni2 - OK Flux 10.62 - S A FB 1 55 AC H5Wm: 13.27+10.62 S 46 6 FB S2Ni2 OK Autrod 12.34 S3Mo - OK Flux 10.62 - S A FB 1 55 AC H5Wm: 12.34+10.62 S 50 5 FB S3Mo -

Wire, flux and EN 756 EN 760 weld metal

Table 2. The filler metals used in submerged arc welding andtheir EN classifications.



20 45º-1/2-V 55 98 5 Wm 177 162 155Fl 179 225 198Fl+1 240 205 162Fl+5 283 274 270Parent material 299 299 270Requirement: M min 40 - -Requirement: ML - - 27

40 60º/90º-X 80 59 3+3 Wm 136 73 44Fl 207 199 185Fl+1 243 233 242Fl+5 299 229 119Parent material - - 230Requirement: M min 40 - -Requirement: ML - - min 27

20 45º-1/2-V 55 98 5 Wm 156 112 79Fl 127 71 63Fl+1 123 149 127Fl+5 228 188 181Parent 214 191 173materialRequirement: M min 40 - -Requirement: ML - - min 27

40 60º/90º-X 80 59 3+3 Wm 203 157 102Fl 210 164 156Fl+1 241 207 195Fl+5 261 258 168Parent material - - 326Requirement: M min 40 - -Requirement: ML - - min 27

Plate Joint Heat Cooling time Number of Impact test: Impact Impact Impactthickness preparation input t8/5 passes location energy energy energy(mm) Q (s) -20ºC -40ºC -50ºC

(kJ/cm) (J) (J) (J)

Table 3. The impact toughness of welded joints in S420 M/ML steel.

• Submerged arc welding.• Filler metals: OK Autrod 13.27+OK Flux 10.62.• Preheating: No.• Interpass temperature: 50-80 ºC.• Wm = weld metal, Fl = fusion line, Fl+1 = fusion line + 1 mm etc.• Impact energy: mean of three tests.

Table 4. The impact toughness of welded joints in S460 M/ML steel.

• Submerged arc welding.• Filler metals: OK Autrod 13.27+OK Flux 10.62.• Preheating: No.• Interpass temperature: 50-80ºC.• Wm = weld metal, Fl = fusion line, Fl+1 = fusion line + 1 mm etc.• Impact energy: mean of three tests.

Plate Joint Heat Cooling time Number of Impact test: Impact Impact Impactthickness preparation input t8/5 passes location energy energy energy(mm) Q (s) -20ºC -40ºC -50ºC

(kJ/cm) (J) (J) (J)

ing time for the weld is the same (60 s) even though theheat input is only one-third of the above, i.e. 25 kJ/cm.Thick plates withstand considerably higher heat inputsthan thin plates.

This research, leads to the conclusion that, when dealingwith multi-run welding of thick plates, surprisingly highheat inputs can be used in submerged arc welding appli-cations without impact toughness properties being exces-sively impaired.

Strength not a problemWhen transverse tensile tests were performed onwelded joints, the majority of the test specimens brokeon the parent material side - all the results fulfilled the

requirements set on the parent material (not reportedin this shortened article). Even the highest heat inputsof 70-80 kJ/cm did not soften joints to such an extentthat this would have been essentially manifested in thetensile test results.

SummaryAs a means of reducing labour costs and of improvingproductivity, maximum heat input must be appliedwhen welding. However, in order that sufficient impacttoughness properties might be obtained in the weldedjoint, it is at times necessary to restrict the maximumheat input. The need for restriction is so much thegreater, the lower the temperatures at which goodimpact toughness properties are required, the greater


20 45º-1/2-V 31 35 6 Wm - 110 62 Fl - 101 31 Fl+1 - 225 196Fl+5 - 104 45

“ 37 45 5 Wm - 129 55 Fl - 136 88 Fl+1 - 207 160 Fl+5 - 108 66

“ 43 60 5 Wm - 84 61Fl - 109 56 Fl+1 - 167 144 Fl+5 - 91 91

“ 55 98 4 Wm - 100 57 Fl - 111 39 Fl+1 - 179 136 Fl+5 - 79 70

“ 60º-V 50 81 2+1 Wm 42 25 17Fl 101 66 35 Fl+1 115 78 37 Fl+5 183 134 52 Parent material: - 114 64 Requirement: - min 40 -

40 60º/90º-X 70 40 3+3 Wm 72 69 35Fl 111 63 35 Fl+1 80 53 27 Fl+5 105 51 27

“ 45º-K 71 43 3+4 Wm - 40 38 Fl - 109 70 Fl+1 - 90 79 Fl+5 - 175 174 Parent material: - 186 165 Requirement: - min 40 -

Plate Joint Heat Cooling time Number of Impact test: Impact Impact Impactthickness preparation input t8/5 passes location energy energy energy(mm) Q (s) 0ºC -20ºC -40ºC

(kJ/cm) (J) (J) (J)

Table 5. The impact toughness of welded joints in RAEX Multisteel.



20 45º-1/2-V 31 35 6 Wm - 95 61 Fl - 112 79 Fl+1 - 178 125 Fl+5 - 43 19

“ “ 37 45 5 Wm - 103 58 Fl - 120 60 Fl+1 - 132 52 Fl+5 - 51 20

“ “ 43 60 5 Wm - 113 52 Fl - 80 44 Fl+1 - 90 58 Fl+5 - 74 45

“ “ 55 98 4 Wm - 73 31 Fl - 57 32 Fl+1 - 112 56 Fl+5 - 50 29

“ 60º-V 50 81 2+1 Wm 48 21 13 Fl 47 31 20 Fl+1 55 35 25 Fl+5 76 71 23 Parent material: - 43 28 Requirement: - min 27 -

40 60º/90º-X 70 40 3+3 Wm 70 56 27 Fl 94 62 34 Fl+1 73 45 27 Fl+5 104 46 33 Parent material: - 83 - Requirement: - min 27 -

Plate Joint Heat Cooling time Number of Impact test: Impact Impact Impactthickness preparation input t8/5 passes location energy energy energy(mm) Q (s) 0ºC -20ºC -40ºC

(kJ/cm) (J) (J) (J)

are the tensile strength requirements, and the thinnerthe plate being welded.The research showed that modern-day steels and weld-ing filler metals can withstand surprisingly high heatinputs when welding thick plates and using multi-runarc welding.

In a light-hearted sense, one could say that the resultsfor the heat-affected zones and weld metals were suchthat the “traditional impact toughness competition”between steel manufacturer Rautaruukki and fillermanufacturer ESAB ended in a draw!

Table 6. The impact toughness of welded joints in S355J2G3 steel.


About The Authors:

JUHA LUKKARIIs Head of Technical Service Department at ESABOy, Helsinki, Finland

OLLI VÄHÄKAINUIs Product Manager at Rautaruukki Steel, Raahe,Finland

AcknowledgementWe thank BrasFELS production management for theirsupport in producing this article.

In Brazil, offshore fields supply 80% of the country’soil requirements, some 60% coming from very deepwaters, underlining the importance of offshore opera-tions for the Brazilian economy. As a consequence,there is a very high level of offshore activity.BrasFELS has recently built two FPSO vessels for theCaratinga and Barracuda oil fields (Figure 1), and hasanother two FPSO vessels in its order book.

OK Tubrod 75The Caratinga FPSO was completed earlier this year.Two consumables were widely applied, OK Tubrod 71Ultra (E71T-1) for FCAW of components for a servicetemperature down to –30°C and the basic OK 55.00(E7018-1) stick electrode for the welding of EH36 witha CVN impact requirement down to –40°C. For the construction of the Baracuda FPSO, a higherwelding productivity was required and the yard evaluated

other consumables and processes. Replacement ofMMA with OK 55.00 by FCAW was considered aviable option for increased productivity, provided thatthe new consumable yielded at least the same mechan-ical properties. OK Tubrod 75, a development ofESAB’s Brazilian cored wire factory, was evaluated byBrasFELS and was judged to be the best available.

OK Tubrod 75 is an all-position basic cored wire (E71T-5/E71T-5M) for use in both CO2 and Ar/CO2 shieldinggas. For reasons of availability and optimum outdoorgas shielding, the BrasFELS yard prefers the use ofCO2. Table 1 surveys the chemical composition andmechanical properties of OK Tubrod 75 in the as-weld-ed condition. Table 2 gives an overview of the satisfac-tory results of tensile, bend, impact and hardness testsderived from the Welding Procedure Specifications inEH36. ESAB Brazil assisted the BrasFELS yard in theestablishment of these procedures and obtained thenecessary ABS approval (4SA, 4YSA H10).

Table 3 and 4 give the Welding Procedure Specificationsin 2G and 3G positions for a 60° V-joint with a nominalroot opening of 8mm and a land of 1mm, in 25mm platethickness. Root passes are welded on ceramic backingstrips.


ESAB Brazil provides BrasFELS shipyard with extra FCAW productivityfor offshore vessels By: José Roberto Domingues, Technical Manager Consumables and Cleber J.F.O Fortes, Technical Assistant, ESAB Brazil.

The BrasFELS shipyard, in Angra dos Reis, Brazil is involved in the conversion ofpetroleum tankers to FPSO (Flotation-Production-Storage-Operation) vessels. OK Tubrod 75 all-position basic cored wire, a Brazilian development with European,US and Korean equivalents, passed the yard’s extensive qualification tests to provideextra FCAW productivity.

Figure 2. Conversion to FPSO vessel.

Figure 1. Barracuda & Caratinga Project.

ProductivityThe conversion from MMA to FCAW yielded similarbenefits in productivity as those previously achieved byBrasFELS when they introduced OK Tubrod 71 Ultra.The comparative performance of table 5 is based on astandard cost calculation applied by the yard. Theresulting improvement in relative welding costs is near-ly 35% which is a welcome reduction for any shipyard.

Note: OK Tubrod 75 is a local product for the Brazilianmarket. Basic ESAB types for offshore fabricationwith a comparable performance are:

OK Tubrod 15.24 and FILARC PZ6125 for Europe.Dual Shield T5 for the US and Asia Pacific.


About the authors

José Roberto Domingues is Technical ManagerConsumables for ESAB Brazil. He is responsible for theR&D and quality control of welding consumables andtheir applications. He joined ESAB in 1988.

Cleber J.F.O. Fortes is Technical Assistant in the field ofarc welding consumables. He has been involved in wel-ding for over 20 years, and joined ESAB in 2001.

Typical chemical composition of the weld metal (%)C Si Mn

CO2 0.040 0.50 1.50Ar+CO2 0.055 0.53 1.68

Typical mechanical properties of the weld metalStrength Yield Elong. Impact(MPa) (MPa) (%) (J) at -40ºC

CO2

(DC-) 480 400 22 90

Ar+CO2

(DC+) 480 400 22 40

Ø Dep. Net dep. Relativerate rate cost

(mm) (kg/h) (kg/h) (%)

OK 55.00 4.0 1.75 0.52 100OK Tubrod 75 1.2 2.78 1.11 65.5

Table 1. Typical properties of OK Tubrod 75.

Table 5. Welding costs.

Welding Process: FCAW Position: 2GBase Material: EH 36 Thickness: 25.4 mmFiller Metal: OK Tubrod™ 75 Ø 1.2 mmClassification: AWS A 5.20 E71T-5 (M)Shielding Gas: CO2 / 18 L/minPreheat: 21ºC min. Interpass: 250ºC max.Technique: Maximum weave 25.0 mmElectrode extension: 10 - 15 mmCurrent / Polarity: DC-

Weld Current Voltage Travel HeatLayer Speed Input

(A) (V) (mm/s) (kJ/mm)Root 140 24 1.1 3.12nd Pass 130 24 3.5 0.9Fill 160 25 4.7 0.9Cap 175 25 4.7 0.9

Welding Process: FCAW Position: 3GBase Material: EH 36 Thickness: 25.4 mmFiller Metal: OK Tubrod™ 75 Ø 1.2 mmClassification: AWS A 5.20 E71T-5 (M)Shielding Gas: CO2 / 18 L/minPreheat: 21ºC min. Interpass: 250ºC max.Technique: Maximum weave 25.0 mmElectrode extension: 10 - 15 mmCurrent / Polarity: DC–

Weld Current Voltage Travel HeatLayer Speed Input

(A) (V) (mm/s) (kJ/mm)Root 150 23 0.6 5.82nd Pass 130 22 1.3 2.2Fill 130 22 3.0 1.0Cap 130 22 3.3 0.9

Table 3. Welding procedure data, 2G position.

Table 4. Welding procedure data, 3G position.

60º

25.4mm

8.0mm1.0mm

Figure 3. Bevel configuration.

Tensile tests2G 550 MPa, ductile fracture in base metal

580 MPa, ductile fracture in base metal3G 530 MPa, ductile fracture in base metal

540 MPa, ductile fracture in base metal

Side bend tests: no cracks

Impact tests (J) at -40ºCWeld centre Fusion line Fusion line Fusion line

+2 mm +5 mm

2G 36 / 44 / 48 126 / 44 / 44 30 / 40 / 30 70 / 72 / 34av. 42.7 av. 71.3 av. 33.3 av. 58.7

3G 36 / 28 / 28 22 / 58 / 76 40 / 32 / 66 90 / 56 / 52av. 30.7 av. 52.0 av. 46.0 av. 66.0

Hardness tests (HV5)Base metal Weld metal Heat affected zone

2G 157 - 185 201 - 236 185 - 2863G 160 - 177 189 - 244 191 - 248

Table 2. Destructive tests.

OK TUBROD 75

COMPARATIVE PERFORMANCE

WELDING PROCEDURE, 2G POSITION

WELDING PROCEDURE, 3G POSITION

DESTRUCTIVE TESTS

Secure fillet weld penetration with downhillMAG weldingOngoing development of the OK Tubrod 14.12 metal-cored wire has resulted in a consumable with a verysecure penetration that avoids the above mentionedwelding defects associated with downhill MAG weld-ing. The weld penetration depth has been recordedbetween 1.3 and 2.0mm when using CO2 shielding gasand between 1.0 and 1.5mm for M21 mixed gas. Thesedepths are comparable to the very secure penetration


Secure downhill MAG welding of butt- and fillet welds with ESAB OK Tubrod 14.12Translation of an article first published in Fenster, the ESAB Germany customer magazine.

By: Dipl. Ing. Frank Tessin, ESAB GmbH, Solingen, Germany.

The downhill welding of fillet welds by the MAG process is regarded as an insecuremethod by many in the welding industry, and is, therefore, rarely used. Some Germanshipyards, however, have successfully developed and applied downhill welding proce-dures for thin-walled applications using OK Tubrod 14.12 metal-cored wire.

Root defectsWelding defects in the root of the weld, associated withdownhill MAG welding, have made shipbuilders reluc-tant to apply this method, in spite of the productivitybenefits offered by the process. Typical root defects are:

• Lack of penetration.• The occurrence of slag or slag particles in the back

of the root when using flux-cored wires.• Lack of fusion when using solid wire.

observed in uphill welding with rutile flux-cored wires.OK Tubrod 14.12 is normally welded with – polarityand welding parameters are carefully adjusted toobtain optimum weld penetration. With a single bead,fillet welds with a thickness of a=2.5 to 3.5mm are per-fectly feasible. Thicker fillet welds must be uphill weld-ed with rutile flux-cored wire or downhill depositingmulti-beads with OK Tubrod 14.12.

It is essential to avoid pushing-up the arc, in order toobtain a large fillet weld thickness. In this case, the arcwill burn onto a large weld pool which will go at theexpense of the good weld penetration.

Additional benefitsAdditional benefits of the downhill MAG welding offillet welds with OK Tubrod 14.12 are:

• A concave weld cross section without undercut.• A smooth fine-rippled weld surface.• A low heat input (4-5 KJ/cm).• Minimal distortion.• A high welding speed (50-70 cm/min.).

A new fabrication method for butt weldsExploring the possibilities of this high penetrationwelding consumable, german shipyard HDW Kiel,tested the vertical down welding of butt welds. Theresults were remarkably positive and led to a com-pletely new production technique by which I-joints, inplate thickness 3 to 7mm, and V-joints, in plate thick-ness >8mm, are welded extremely fast and without


Figure 7. Weld pool ofthe root layer.

Root

Figures 4 to 6. building-up of runs, square butt weld, t = 7 mm; vertical down welding.

2mm gap 3mm gap

4mm gap 5mm gap

Figure 8. I-butt, t = 6 mm. Gap bridging possibility of the OK Tubrod 14.12 at gap variation.

Figure 2a. Penetration, verticaldown welding with solid wire.

Figure 2b. Penetration, verticaldown welding with metalpowder wire XX (pos. pole).

Figure 3. safe penetrationin vertical down weldingwith OK Tubrod 14.12.

Root with final run on either sideRoot with 1st final run

ceramic backing material. The I-joints are given a larg-er than normal root gap, and during welding a phe-nomenon occurs that has not been observed before inwelding. Under the influence of the arc and the veryhot weld pool, the plate edges are securely meltedwithout any fusion faults, while the root is contractedalong the centerline of the joint.The root is exactly located in the neutral zone of theplates, resulting in a total absence of angular distortiondue to shrinkage – a problem that is almost alwayspresent when welding thin plates and requires cumber-some straightening work.

A further benefit of this type of root is that it has a verysmooth tie-in, avoiding fusion faults when welding sub-sequent layers.This technique is applicable for plate thicknesses from5-7mm. For thinner plates, the common two layertechnique is being used, with a smaller root gap. Withplate thickness above 8mm, there is a risk of fusiondefects. Because of the high welding speed, the heatinput is no longer sufficiently high to melt the weldedges thoroughly. This can be solved easily, however,by changing the joint to a V-design where the plateedges require less energy to be melted. From the yard’sresearch it was concluded that the downhill welding ofV-joints is possible up to plate thickness of 12-15mm.For the welding of I-joints up to 7mm thick, a few mil-limeters root gap tolerance is acceptable without lead-ing to any problems (figure 8).

Metallurgically perfectThe welded joints are easily tested by X-Ray. Fusionfaults introduced by lack of skill give clear indications.The excellent mechanical properties have been con-firmed by various tensile, bend and CVN impact tests.Weld metal and HAZ hardness increase has not beenobserved.

A higher productivity and increased flexibilityProductivity calculations yield a welding time that isreduced by 80% for 4mm thick plate, compared withsolid wire MAG welding. The savings on straighteningwork are even substantially higher. Even for 8mmplate, compared with rutile flux-cored wire, savings areachieved, apart from reduced straightening work. Another aspect to be considered in relation to V-jointsis the flexibility. Should fit-up work result in too largea root gap, one can always revert to uphill welding withrutile wire and ceramic backing. Root gaps that are toosmall can be covered downhill with OK Tubrod 14.12metal-cored wire. Corrective work during fit-up of thejoints is, therefore, never needed.


About the author

Frank Tessin, M.Sc, is Product Manager Cored Wiresat ESAB in Germany.He studied mechanical engineering and started wor-king for ESAB in 1992.Since two years, he is also Key Account Manager forESAB's automotive business in Germany.

Conclusions and outlook HDW has obtained approval from GermanischenLloyd, Lloyds Register, and BWB for the welding offillet welds and butt joints for shipbuilding steel gradesA up to D36. The process has been used now for a cou-ple of years and has resulted in clear savings andincreasing weld quality. The fillet welds are slightlyconcave without undercut, and the weld surface issmooth with a fine ripple. The butt welds are narrowand show only a small over-thickness. The vertical down welding of fillet welds with OKTubrod 14.12 is relatively easy to learn and investmentin new welding equipment is not needed. Welders willsoon produce good quality welds, while applying thefast travel speeds involved. This is not equally valid forthe vertical down welding of butt welds, however. Ittakes time for welders to develop the skill and to pro-duce consistently high quality welds. Vertical down welding with OK Tubrod 14.12 is nowa-days the most economic solution for joining thin-walled plates. At the yards involved, it has becomecommon practice to place constructions in the verticalposition to benefit as much as possible from the eco-nomic advantages.The new method will undoubtedly change the future ofthin plate welding, in general. Further progress may beexpected from consumable development and dedicat-ed use of industrial shielding gas mixtures.

At first glance, the bevelling of plate edges may lookeasy, but it requires considerable knowledge and expert-ise to build an installation that cuts accurately and fastand that is, at the same time, user-friendly. Over morethan 70 years, ESAB Cutting Systems has used its glob-al experience in cutting installations to further improveeach generation of control units. The result is continu-ing improvements and simpification in programmingand the use of cutting installations. This constant inno-vation, results in lower bevelling costs, higher produc-tivity, and increased customer competitiveness.

Bevel shapesThe welding of medium and large thickness platesrequires a weld joint preparation which can be either aV-,Y-,K- or X- bevel, depending on the weldingprocess, application and plate thickness.

When welding, the accuracy of the angle and the cutquality are very important, but the straightness of thecut is critical. If it is not perfectly straight, the root gapwill vary and unacceptable weld defects are more like-ly to occur; this apart from the fact that the joint vol-ume increases and more filler material is needed.

This is precisely the reason why ESAB has carefullydesigned high accuracy height control devices andincorporated them into all its bevelling tools. Thesedevices are independent from the cutting process itself,which varies with the cutting needs of fabricators.

Another important aspect for consideration is the cut-ting length. It is larger than the plate thickness and cor-responds to the plate thickness/COS angle.


Thermal Bevelling TechniquesBy: Arnaud Paque, ESAB Cutting Systems, Karben, Germany.

The article discusses the thermal bevelling techniques available fromESAB highlighting several cutting processes and a variety of plate edgepreparation applications.

H2

L2H2

H1

H1

If Angel = 45º

H2=L2

Figure 1a, 1b, 1c. V-,Y-, X- and K- bevels

Figure 2. Cutting angle.

Figure 3. Cutting length.

V- and Y- bevels with an angle of 20 to 45° are normallyused for plate thicknesses from 10mm to 75mm.

X-bevels with an angle of 20 to 45° are applied from 15mmto 75mm plate thickness.

K-bevels with an angle of 20 to 45° are used from 20mm to 75mm plate thickness.

Cutting lengthAngle

Plate thickness

Cutting processesDifferent thermal cutting processes can be used forbevelling and all have their specific advantages:

Oxy-fuel cutting.The earliest technology to be incorporated in gantry cut-ting machines, and still one of the most cost-effective cut-ting processes. Oxy-fuel cutting is, however, limited tothe use of carbon steel and is not suited for aluminium,stainless steel, brass or copper. When used for bevelling,it is limited to a plate thickness of 75mm and a 45° angle.

Plasma cutting.Can cut all electrically conductive materials, includingstainless steel, aluminium, and copper alloys. Plasmacutting is the best choice for thinner materials, especial-ly for non-carbon steels. The cutting speed is up to 6times higher than with oxy-fuel cutting. The cuttingthickness depends on the plasma source, but the processis commonly used for plate material up to 30mm thick.

Laser cutting.The laser cutting process itself allows cutting carbonsteel up to 30 mm, but the bevelling capacity does notexceed a plate thickness of 12mm. It provides anextremely accurate cut with a very small kerf widthand an excellent edge quality, making any secondarymachining process obsolete.

Weld edge preparation of a rectangular plateWhen a plate just needs to be cut to the right size, intransverse and longitudinal directions, a manual bevel-ling head can be used (+/-90°). The angle setting from15° to 45° is made manually, and the head can make astraight cut without contour.

The height of the head is adjusted via a wheel castorwhich guarantees a constant height control.

Main features:• Floating device with castor wheel for cutting

V-,Y-,K-, and X-bevels from ~10 tot 75mm materialthickness and capacitive height control for verticalcutting up to 120 mm.

• Up to 45° manual angle setting adjustment of thelateral torches.

• 200 mm motorised height adjustment.• Manually rotatable head (+/- 90°) which can be

installed on the SUPRAREX type of machines.

This solution provides a very good investment/per-formance ratio.

Weld edge preparation of a contourThis involves most of the applications requiring bevelshapes. In this typical case, the bevelling head followsthe contour and must always be perpendicular to thecontour. The ESAB numerical controller controls, inreal time, the tangential position of the head relative tothe contour, in order to guarantee optimal accuracy.The programming is easily achieved by the use ofAuxiliary Functions (AF), enabling a full control bythe NCE. The endless rotating head allows bevelling toany shape, even a spiral.

Figure 4. Manual bevelling head.

Figure 5. Manually rotatable head.

Figure 6. The endless rotat-ing head allows bevelling toany shape.

Figure 7. The tangential posi-tion of the head relative to thecontour.


Main features:• Endless rotating head which allows any kind of

bevel shape.• Linear potentiometer height control with air cooled

sensor foot, for bevel cutting of V-, Y-, K- and X-joints, offering:• Highly accurate bevel height control of +/- 0.3° for

absolute cutting straightness, due to the externalsensor foot.

• The sensor air cooled foot has a long life cycle.• An air stream blown through the sensor foot

ensures the removal of small slag particles andkeeps the head at a constant height, resulting inless straightness variation.

• The sensor foot can be pneumatically lifted for posi-tion rotation and is equipped with a drop-off safetydevice for plate ends or holes.

• Up to 45° manual angle setting of the lateral torch-es and 70 to 185mm lateral torch adjustment.

• Vertical height setting via capacitive ring.• 200mm motorised height control.• The head is automatic (CNC) and infinitively rotat-

ed for contour. It can be installed on SUPRAREXmachines, type P2 and P3.

Weld edge preparation of a contour andautomatic bevel adjustmentThis bevelling head has the same functions as the pre-vious head, but all torch settings, such as lateral torchadjustment and bevel angle per torch, are fully CNCcontrolled.

In the fabrication of, for example, wind mill towers, itis quite common to connect plates of different thick-nesses, requiring separate weld edge preparations. Inaddition, and also occurring in the shipbuilding indus-try, the joint angle varies from one side to another, oreven varies continuously. In these cases, the numericalcontroller has to control and adjust the angle and thelateral torch adjustment, automatically.

The use of such a fully automated bevelling head guar-antees: • a high productivity, because the machine is not

stopped at each change of bevel setting.• a high accuracy due to the CNC controlled setting of

the bevel angle.


Figure 8. Up to 45° manualangle setting of the lateraltorches.

Figure 9. The endless rotat-ing head allows any kind ofbevel shape.

All programming is easily achieved by using AuxiliaryFunctions, making this sophisticated head very easy touse.

Main features:• Endless rotating (CNC) which allows any kind of

bevel shape.• CNC controlled lateral torches and angle setting.• Linear potentiometer height control with air cooled

sensor foot, for bevel cutting of V-, Y-, K- and X-joints, offering:• absolute high accurate bevel height control of +/-

0.3° for absolute cutting straightness, due to theexternal sensor foot.

• The sensor air cooled foot has a long life cycle.• An air stream blown through the sensor foot

ensures the removal of small slag particles andkeeps the head at a constant height, resulting inless straightness variation.

• The sensor foot can be pneumatically lifted for posi-tion rotation and is equipped with a drop-off safetydevice for plate ends or holes.

• CNC angle setting of the side torches from 20° to49° with lateral torch adjustment.

• Vertical height setting via capacitive ring.• 200mm motorised height control• This head can be installed on the NUMOREX and

TELEREX machines.

Figure 10. Any kind ofbevel shape is allowedby the endless rotatingCNC controlled head.

Figure 11. CNC angle settingof the side torches from 20°to 49° with lateral torchadjustment.

Figure 12. In the fabrication of windmill towers, plates of dif-ferent thicknesses are often connected.

Weld edge preparation of a contour andautomatic plasma bevelThis unit is the most robust and precise plasma bevel-ling head. All electrically conductive material can bebevel cut from -45° to +45° with a fixed bevel angle, orcontinuously. The endless rotating head allows cuttingof any shape. The plasma process cuts bevels up to 6times faster than the oxy-fuel process, particularly onthin material. It is mostly used for cutting V-bevels orto compensate its own natural degree bevel angle onthe cut face.

To reach optimal bevel straightness and cut part accu-racy, ESAB has equipped their controller with auto-matic compensation software for all natural deviationsof the plasma process:

• The plasma naturally generates a few degree ofbevel angle.

• The bevel angle naturally varies somewhat with thematerial thickness.

In order to automatically compensate for these devia-tions, ESAB has created and integrated an organisa-tion programme - which is a customer updatable data-base that compensates and guarantees the beveldegree accuracy to 1°. As many databases as necessarycan be created depending on the material range.

As previously stated, height control is one of the mostimportant factors to be considered. With the plasmaprocess, the cutting arc length changes with the bevelangle and is, therefore, not accurate enough to be used


as a reference for the height control. Moreover, thecondition of the consumables changes during their life-cycle. This is the main reason why ESAB very precise-ly controls the height with an external height foot sen-sor that guarantees extreme cut accuracy.

Industries, such as shipbuilding require specific bevel-ling applications where the architecture of NCE pro-gramming brings out its full power. In fact, it’s quitecommon in shipbuilding to create a panel with differ-ent plate thicknesses, which must also be bevel cut. Inother words, all the power is inside the NCE, pro-gramming being easy and user-friendly. By also using,the cutting parameters databases which can set all cut-ting parameters (amperage, gas pressure etc.), themachine can work automatically. In this typical appli-cation, straightness must be guaranteed, meaning thatthe NCE has to interpolate the plate thickness, in realtime. With the organisation programme module andthe cutting parameters database, this can be very effi-ciently achieved with the straightness being absolutelyperfect for the welding application.

Main features:The bevel angle rotating point (angle-lateral calcula-tion) can be automatically shifted from the upper tothe lower side of the plate (depending on kerf and cut-ting direction).

• Bevel height control accuracy less than ± 0.3 mm.• The bevel angle can be continuously (interpolated)

changed within one linear contour block or withinnumerous following blocks.

• The programmed cutting speed will be continuouslyadjusted for the change of bevel angle.

• Bevel angle setting accuracy: ± 0.2°• Straightness of the cutting edge: ± 0.5 °

within 1000mm.• The organisation programme module.• Can compensate the angle variation up to ±1º.• Can consider the upper melting radius.• Can reduce the repeatable dimension tolerances to

± 2mm & bevel ≤ 30 º at 15mm thickness.• Installation on NUMOREX and TELEREX type

machines.

Figure 13. The precision plasma beveling head.

Figure 14. Bevel degree accuraty of 1º.

Figure 15. Panels with different platethicknesses are common in shipbuilding.

Weld edge preparation of a contour andautomatic laser bevelThe laser head also facilitates automatic, low powercutting and marking sequences. Due to the narrowkerf and low heat distortion, the laser process enables,under certain circumstances, complex bevels such as Y,K, and X, to be performed in 2 or 3 paths.

The laser head can carry out a bevel cut from – 45° to+45°, fixed or tapered-off. The resonator is directlyinstalled on top of the gantry enabling cutting and bev-elling operations of up to 4.5 - 5m width with almost nolimitation in terms of length. This is really convenientfor the laser bevel cutting of longparts. The multi-axis bevel cutting head works with thehighest level of precision. This ensures a smooth cut-ting process and results in a high quality laser cut.

Main features :• Endless rotating head (CNC) which allows any kind

of bevelling shape. To be installed only on theALPHAREX range of machines.

• Bevelling capacity up to 45° on 10mm carbon steeland 30° on 12 mm carbon steel.

• CNC controlled lateral torches and angle setting. • High accurate bevel height control via the capacitive

nozzle.• Less heat distortion.• Y-, K- and X -bevels possible under certain circum-

stances.• Marking and cutting possibilities.


Figure 16. The laser head can carry out a bevel cut from –45° to + 45°.

Figure 17. The smooth cutting process results in a highquality laser cut.

Figure 18. Bevelling capacity up to 45° on 10mm carbonsteel and 30° on 12mm carbon steel.

About the author

Arnaud Paque MSc. has been in the cutting industrysince 1989. He is Global Cutting Marketing Directorand Sales Manager Cutting for Western Europe.

Stub-ends Spatter&

A latest range of plasma cuttingmachines from ESAB uses newproduction technologies to improvematerial utilization and increaseplate handling efficiencies. The Eagle series of plasma cuttingmachines combines advanced pre-cision mechanical engineering withrecently developed Super RapidInitial Height Setting System(SRHISS) technology to increaseboth the speed and quality of cut-ting across a wide range of materi-als and plate sizes. The combina-tion of additional speed and bettermaterial utilization results in a newcutting solution that delivers thelowest possible unit cost for compo-nent production. A number of newdevelopments come as standardthat includes the ESAB anti-colli-sion system.

With the Eagle, both the markingand the cutting operations sharethe same torch and only one elec-trode is needed on the plasma for

the full thickness range. The cuttingsettings are adjusted automaticallyfrom an on board database which iscontrolled and monitored by aVision PC Controller.

The introduction of these latestEagle machines reinforces ESABCutting Systems’ strength in offer-ing complete and totally integratedturnkey solutions. These packagescombine cutting machine, processexpertise, numerical controller,programming, cutting table and fil-ters to deliver simple to use, highlymechanized solutions. With a cut-ting width of up to three metres andincorporating automatic adjust-ment of cutting parameters accord-ing to plate thickness, the Eagle canoperate at speeds of up to 35 metresper minute with high point to pointacceleration.

ESAB Eagle machines aredesigned to give a compact anduncomplicated appearance, but

beneath this outward design-sim-plicity exists an advanced mechani-cal design solution that incorporatesa transverse linear guiding systemfor increased stability and accuracy.The rails are positioned lower thanthe cutting table with a minimumspace of 250mm between the tableand the track to ensure an easyup/download of the work plate andcut parts.

The VisionPC controller is free-standing to minimize space and thecutting torch is installed with ananti-collision system that allowscomplete removal of the head. Thisfeature avoids the risk of impactdamage and provides for the easyinterchange of service parts by beingable to remove the torch from itssupport.

Different plate materials such ascarbon steel, aluminium and stain-less steel and of differing thicknesscan be cut in sequence whilst on thesame table, thanks to ESAB’snumerical controller (with automat-ic database) and precision plasmasource. For example, one press ofthe start button immediately initi-ates marking of the first plate, thenswitches to cutting mode beforeautomatically moving to mark upthe second plate and to repeatingthe cycle through to the third plate.Travel time is 35 metres per minuteand, despite the varying thickness ofthe work plates, the height re-set-ting cycle time is less than two sec-onds for each plate.

NEW EAGLE PLASMA CUTTING MACHINE COMBINES HIGH SPEEDPRECISION OUTPUT WITH EFFICIENT MATERIAL UTILIZATION


ESAB’s new AristoMig Universalwelding machines are suitable forwelding virtually all weldable met-als, ranging from mild steel to themost advanced nickel-based stain-less steels and aluminium. As wellas MIG/MAG and pulsed MIG, theunits can also be used for DC-TIG,pulsed TIG and MMA welding, orfor Carbon Arc gouging.

Notwithstanding this remarkableversatility, the AristoMig Universalmachines produce high-qualitywelds and allow the user to workextremely efficiently.

Customers can choose models with a320, 400, 450 or 500 Amp power sup-ply and there is an optional water-cooling unit that is suitable for bothMIG welding guns and TIG torches.Two compatible wire feeders are alsoavailable, namely the AristoFeed 30-4 and AristoFeed 48-4.

For controlling the welding system,customers can specify either thenew U6 control panel or theAristoPendant U8 control pendant.Both are highly advanced units onwhich up to 99 sets of weldingparameters can be stored, and the

ESAB’S UNIVERSAL WELDING MACHINES ARE ULTRA-VERSATILE

controllers are delivered with anumber of pre-programmed syner-gic lines that enable users to startwelding as quickly as possible. If a customer has a number ofAristoMig Universal machines car-rying out similar tasks, theAristoPendant U8 can be used totransfer welding parameters veryquickly via a memory card.

Furthermore, ESAB has also devel-oped a PC programme to handle thesynergic lines created on anAristoPendant U8. These synergiclines can then be downloaded toAristoMig Universal machinesequipped with either the U6 controlpanel or the AristoPendant U8.Thanks to the use of stored synergiclines and the versatility of the weldingmachine itself, the AristoMigUniversal is simple enough to be usedby inexperienced welders, but sophis-ticated enough that skilled users canachieve exceptional results in a verywide variety of applications.More information about theAristoMig Universal and associatedaccessories is available in a newESAB brochure.

ESAB and PERMANOVA of Mölndal, Sweden, have announ-ced an agreement under which thetwo companies will co-operateclosely in the development of laser-hybrid welding systems.

Bringing together ESAB's vastknowledge of welding & cutting andPERMANOVA's expertise in laserprocessing, the new combination isideally situated to serve the worldmarket with the very latest in laser welding and cutting technology.Both companies are already marketleaders in their sectors, and this pre-eminence will be reinforced with thenew agreement.

PERMANOVA, as a producer oflaser systems, is renowned world-wide for its expertise in laser process

tools and high power fiber optics. Itholds a strong position in the auto-motive industry with robotisedlaser solutions for welding, cutting,brazing, hybrid welding, hardeningand marking.

The main focus of the new combina-tion will be on laser-aidedMIG/MAG welding, a very produc-tive and high quality weldingprocess with a wide range of applica-tions in welded fabrication.

ESAB AND PERMANOVA JOIN FORCES IN LASER-HYBRID WELDING


ESAB is launching the ESABMigrange of versatile, heavy-duty weld-ing machines that is packed withadvanced features based on provenESAB technology. The powerful andeconomical semi-automatic rangegives both outstanding welding per-formance and exceptional reliability.

Designed for heavy industrial use,the high-power ESABMig deliversup to 500A at a 60% duty cycle, andis suitable for welding mild andstainless steel from 1.0mm thickand aluminium from 1.5mm thick.High productivity is assured thanksto the ESABMig’s stable arc thatgives excellent welding propertieswhen used with welding wire up to2.4mm in diameter.

Three induction outlets allow thesettings to be easily optimised togive superb welding performanceand characteristics with mixedgases and CO2. Further control isprovided by means of anadjustable crater fill function thatensures a smooth finish and elimi-nates cracks.

The sturdy and robust equipmentis available in a choice of two vari-ants: the ESABMig 400t and theESABMig 500t. Both machinesare housed in a sturdy galvanisedsteel casing with an optional built-in air filter for use in harsh indus-trial environments. Integralergonomic handles are providedto make the units easily portable.

Two new wire feeders, theESABFeed 30-4 and ESABFeed 48-4 complement the ESABMig weld-ing machines. Both feeders benefitfrom four-wheel drive and opti-mised feed roller profiles to ensureexcellent feeding qualities; electron-ic control of the drive wheels helpsto achieve an accurate and stablearc. The two feeders are availableeither with an enclosed spool holderor equipped to use ESAB’sMarathon Pac‘ bulk wire spools.

A synergic control function on thefeeders allows simple, accurate set-ting of the welding parameters, andthere are 14 pre-programmed syner-gic lines for easy single-knob con-trol. Furthermore, another two syn-ergic lines can be created to opti-mise the settings for customer-spe-cific applications. Significant savingsin time, as well as a wide workingradius, are possible by virtue of thefact that all settings can be made onthe wire feeder.

For increased productivity, theESABMig is easily mechanised usingthe built-in connectors for bothRailtrac and Miggytrac. ELP(ESAB’s LogicPump) gives automat-ic starting of the water pump when aPSF water-cooled welding gun is con-nected, thereby eliminating the riskof overheating the welding gun.

ESAB’s new PRH orbital TIGtube-welding tools are easy to oper-ate and capable of connecting thin-walled tubes with butt welds of thehighest quality, regardless of mate-rial; titanium can be welded as eas-ily as stainless steel.

For efficient, quality assured weldingcomprehensive gas shielding aroundthe tube is provided using a systembased on the chamber principle. Allrotating components including thetungsten electrodes are enclosed in asealed chamber formed by the outercasing, which also incorporatesclamping elements to locate andalign the tubes being welded.

PRH tools are available in threesizes, enabling welding of tubesbetween 3mm and 76.2mm diameter.Each PRH tool is water-cooled andforms a complete unit incorporatingthe return conductor. The welding heads are driven byencoder motors for the precise posi-tioning of each sector when weldingwith different sets of parameters.

PRH thus provides a highly effi-cient means of producing high qual-ity welds on metal tubing used inthe most demanding applications.

The equipment is designed forindustries where weld seam finish is

NEW ORBITAL TIG HEADS FOR HIGH QUALITY TUBE WELDING

NEW ESABMIG FOR HEAVY DUTY SOLUTIONS

a key determinant of the quality ofthe product. It is well suited tochemical, food and pharmaceuticalindustry applications in whichsmooth, even internal and externalweld seams are mandatory to satisfyhygiene considerations.


ESAB’s latest welding machinesare the OrigoTig 150 and theOrigoArc 150 designed for the userwho wants simplicity of operation,reliability and high welding per-formance from a compact, robust,easily portable machine. Suitablefor use both indoors and outdoors,the all-new machines operate froma single-phase 230V power supplyand can be used with long mains

leads to give access to areas dis-tant from the power supply.For TIG welding mild steel,stainless steel or many otherweldable metals, the OrigoTigunits offer several sophisticatedfeatures on the back of ESAB’sproven inverter technology. Witha choice of high frequency igni-tion or lift arc, the user is assuredof a reliable, safe start.

Furthermore, adjustable post gas andramp-down helps to avoid cracks andoxidation. The OrigoTig machinescan also be used for MMA welding,in which mode the functions includean automatic hot start, arc force andArcPlus™ to ensure excellent weldquality with simple settings.Users who do not require TIG weld-ing capability, the OrigoArc is a sim-pler machine, though still benefitingfrom ESAB’s inverter technologyand ArcPlus™ for easy starting andexcellent weld quality. Suitable foruse with alloyed and non-alloyedsteel, stainless steel and cast iron, theOrigoArc 150 can be used with elec-trodes up to 3.25 mm in diameter.Very straightforward to use, theOrigoArc simply has a current set-ting on the front panel.

Modern materials and innovativedesign ensure that both theOrigoTig and OrigoArc machinesare compact, robust and easilyportable. A carrying handle is pro-vided on the top of each unit, andthe simple, quick controls enable theuser to move into position and startwelding very rapidly.

ESAB LAUNCHES ALL-NEW PORTABLE WELDING MACHINES FORTIG AND MMA

A major development in the field ofFriction Stir Welding, the LEGIO™modular FSW machines.

With the launch of the LEGIO™modular friction stir welding(FSW) machine concept ESAB ismaking the FSW process applicableto a much wider industrial base.

Use of FSW has hitherto demandedsubstantial investment in a custom-engineered machine. By contrast, aLEGIO™ machine is built fromstandard modules capable of satis-fying most applications. The systemis capable of welding materials from1.2mm thickness to 65mm thicknessfrom one side.

ESAB has been the world's leadingdeveloper of FSW equipment sincethe process was first commercialisedin 1992. A large number ofSuperStir™ machines are now in

service worldwide. The LEGIO™FSW machine concept retains thesame level of functionality but modu-lar construction allows faster deliveryat significantly lower cost. In essence,the customer determines the workingarea, the bed configuration, theclamping arrangement, and the num-ber of heads. Several options arethen available to satisfy the applica-tion requirements, whilst the controlsystem has been developed specifi-cally to handle the FSW process.

The potential market is very largeas the process is extremely versatileand requires no special surfacepreparation. As well as welding twocomponents of the same grade ofaluminium, the FSW process canjoin dissimilar alloys or even jointwo completely different metals. Inmany cases FSW can be used to joinmaterials that cannot be welded byany other means.

UNIQUE MODULAR LEGIO™ FRICTION STIR WELDING EQUIPMENT The relatively modest cost ofLEGIO™ machines will allow fabri-cators to consider FSW for smallbatches of products. Industries like-ly to benefit from the equipmentinclude automotive, aerospace,marine, architectural, constructionand general engineering.


WELDING WIRE FEEDERS GIVECUSTOMERS AMPLE CHOICEAn exceptionally broad range ofrugged welding wire feeders andcontrollers is being launched byESAB for use with a variety of dif-ferent types of welding machine.There is a choice of three alterna-tive feeding mechanisms and ninecontrollers for use with step-con-trolled or thyristor-controlledpower sources.For wire diameters up to 1.2mm,the ESABFeed 30-2 feeder is a two-wheel-drive unit with 30mm diame-ter feed rollers. While the 30-4 feed-er has the same size rollers, it bene-fits from a four-wheel-drive arrange-ment that enables wire diameters upto 1.6mm to be fed. If wire up to2.4mm is to be fed, ESAB offers the48-4 four-wheel-drive feeder thathas 48mm rollers and a pair of drivemotors.

Regardless of which of the ninecontrol panels is selected, all feed-ers include features such astwo/four stroke, adjustable burn-

back time and creep start. Certaincombinations of control panel andpower source also deliver the fol-lowing additional functions: a digi-tal voltage/current meter; craterfilling; 14 pre-programmed synergiclines; and a facility to create twocustomised synergic lines.

To keep the set-up time as short aspossible, all of the connectioncables are of the quick-connecttype, and standard connectioncables are available to enable theworking zone to be extended as faras 35m from the power source.Irrespective of the length of theconnection and return cables,ESAB’s TrueArcVoltage systemensures that the welding currentand voltage are always measuredcorrectly, thereby helping to ensurea consistent weld quality.

If a water-cooled welding gun isbeing used, ESAB’s LogicPump(ELP) starts the water pump auto-matically as soon as welding com-mences. Moreover, if the wire feed-

er is to be used as part of a semi-automated welding system, aremote control output provides a42V AC power supply, start/stopcontrol and remote monitoring andcontrol of the welding current andvoltage, depending on the powersource employed.

To assist with portability, the feed-ers can be equipped with an option-al counterbalance, lifting eye orwheel kit.

More information is available in anew brochure.

ESAB’s latest CaddyTig 150 andCaddyArc 150 welding machinesare designed for use by professionalwelders who are out and about,working both indoors and outdoors.Moreover, the portability and flexi-bility does not come at the expenseof weld quality, which remains highthanks to the incorporation ofproven ESAB inverter technologyand several sophisticated features.

Both the CaddyTig and CaddyArcmachines benefit from an integralvoltage and current meter so that theuser can closely monitor the weldingprocess, and a remote control facilityenables the welding parameters to beadjusted from the torch, in additionto a remote on/off switch.

Suitable for both TIG and MMAwelding, the CaddyTig 150 has high-frequency ignition and Lift Arc,allowing the user to select the opti-mum setting for the ideal start; con-

trol of the pre and post gas flow andthe ramp up/down also helps toensure the weld quality is excellentat the start and finish as well as dur-ing weld passes. When used forMMA welding, there is a furtherfacility for adjusting the hot start,arc force and ArcPlus™ parameters.Up to four sets of welding parame-ters can be stored in the user-friendly controller’s memory of theCaddyTig, two for TIG and two forMMA. These parameter sets caneither be selected from the controlpanel or via the TIG torch switch.Users have the choice of pulse pro-gramming and/or manual pulseswitching when switching betweenthe two TIG parameter sets.

For those who do not need TIGcapability, the CaddyArc 150 can beused for MMA welding of most fer-rous metals, including alloyed andunalloyed steels, stainless steel andcast iron. The CaddyArc 150 han-

CADDYTIG AND CADDYARC WELDING EQUIPMENT IS RUGGED,PORTABLE, AND IDEAL FOR THE MOBILE PROFESSIONAL WANTINGHIGH QUALITY WELDS

dles electrodes from 1.6 to 3.2mmdiameter and has adjustable hotstart, thereby ensuring easy, reliablestarts. Furthermore, the adjustablearc force and the ArcPlus™ helpsto maintain an excellent weld quali-ty, and the high power reserveallows a long mains lead to be used.

ESAB’s CaddyTig and CaddyArcmachines all operate from a stan-dard 230V power supply and areequipped with a sturdy carryinghandle. If a unit is to be frequentlymoved, an optional shoulder strapand trolley are available.


ESAB´s Multiple wire SAWmachine is primarily designed forthe production of longitudinal andspirally welded pipes to maximisethe welding speeds. This is benefi-cial for the customer to achieve theultimate rate of production withoutany deteriation in weld quality.

The travel speed capability is up to10 m/min. This is used for singlewire GMAW (Buried arc transfer)

continuous tack welding with a largediam. (4.0mm) CO2 shielded wire.Common GMAW welding speedsreaches 1.7 m/min.

The Machine handles up to six wiresand can produce deposition ratestowards 100 kg/ hr, (compared to 14kg for single wire operation) this atwelding speeds in excess of 2.6 m/minon pipes with a 15mm wall thickness.

The increased welding speed meanslower heat input, thereby stillretaining the desirable mechanicalproperties, if the right selection of

the applicable flux and wire combi-nation is made.

The Machine is used at ESAB´sProcess Centre in Göteborg, on anongoing basis to develop customisedwelding procedures. This includesnew processes such as ESCW(Electrical Synergic Cold Wire) aswell as the development of new Fluxand Wire combinations for highquality line pipe steels such as X-70and beyond.

The PEH welding controller incor-porates all pre-settable and storablewelding parameters, start and stopsequences, heat input, weldingspeed and the flux on off and recy-cling functions to ensure a reliableand repeatable operation.

The welding joint is tracked mechan-ically (GMD) or with Laser for high-er accuracy at higher welding speedsto avoid welding wire misalignmentdefects in the weldment.

Computerised data logging is avail-able to store all welding parametersfor each welded pipe to enhance therecord keeping in support of theQuality Assurance department.

needs of a CaB welding station.These products support general pur-pose customer needs for conven-tional welding.

"M" is the modular range offeringhigh flexibility to support most cus-tomer requirements for a Columnand Boom welding station. Thesesystems meet most demands interms of performance and handling.

"C" is the customer specific range.This offers very high levels of flexi-bility to support the specific needs ofthe customer. Systems are tailormade according to the specifiedapplication and welding require-ment.

All ESAB CaB products are fullycompatible with the ESAB range ofpositioners and roller beds.

ESAB has launched an expandedrange of Column and Booms (CaB)for mechanised welding of beamsand profiles, large-diameter tubes,vessels and windmill towers. Theequipment can be configured forapplications ranging from basic to theultimate customer specific solution.

The ESAB CaB range now pro-vides column and booms in sizesfrom 2x2m to 10x10m or any per-mutation within that envelope.Column width dimensions are 300,460 and 600mm for the support ofvarious specifications of weldingheads, control equipment, operatorchair and flux handling equipment.

Systems are available in three spec-ification levels: "S" is the standard range with mod-erate flexibility to support the basic

MULTIPLE-WIRE ELECTRODESUBMERGED ARC WELDINGMACHINE

COMPLETE RANGE OF ESAB COLUMNS AND BOOMS


ESAB has developed a new genera-tion of solid stainless steel MIGwelding wires that feature a mattsurface appearance. These wiresprovide improved welding proper-ties and lead directly to enhancedMIG welding performance.

The matte appearance results from anew surface treatment that is part ofan improved manufacturing process.In addition to the surface beingmatte, rather than shiny, the diame-ter has a tighter tolerance and thestiffness is higher. Furthermore, strictcontrol of the cast and helix – both ofwhich are important properties forspooled wires – leads to additionalbenefits.

Taken together, these product char-acteristics give the new wires greatlyimproved feedability and a very sta-ble welding arc, resulting in depend-able performance for the MIGprocess, consistently high weld qual-ity, and minimal post-weld cleaning.ESAB matt stainless steel MIG wiresare available in a range of diameters

resistance are provided by ESAB’sAdvanced Surface CharacteristicsTechnology, ASC.

The new wire produces an excep-tionally stable and spatter-free weld-ing arc. In addition to enabling high-er duty work cycles, resulting inincreased productivity, this spatter-free welding arc also reduces thenecessity and cost of post weld grind-ing.

Contact tip wear, a traditional prob-lem with copper-free wires, has beenimproved to a level superior to cop-per-coated wire, so arc stability isguaranteed over a longer period anddowntime for tip changing is limited.

An environmental advantage thatcomes with copper-free wires is thegreatly reduced amount of copper inthe welding fume and its contribu-tion to a healthier environment inand around the welding workplace.Increasingly health authorities inmany countries are advocating the

ESAB has introduced OK AristoRod,a new family of solid copper-freeMAG welding wires that enablesfabricators to get the best out oftheir welding stations, whether theyare semi-automatic, mechanised orrobotised.

Due to the absence of a copper-coat-ing, there is less risk of clogging ofguns and liners with copper flakes,resulting in less maintenance and ahigher duty cycle. Excellent glidingproperties, low feeding forces, opti-mal current transfer, reduced con-tact tip wear and improved corrosion

ESAB’S NEW MATTE STAINLESS STEEL MIG WIRES IMPROVE WELDING PERFORMANCE

for most commonly used grades ofstainless steel. The wires are sup-plied in 15kg basket spools for semi-automatic welding and 250 or 475kgMarathonPac bulk drums for mech-anised and robotic welding.

As one of the world’s leading sup-pliers of welding equipment andconsumables, ESAB manufacturesits own solid wires for stainlesssteel, un-alloyed and low-alloyedsteel, and aluminium. The newmatte stainless steel MIG wireshave been developed as a directresponse to demand from the mar-ketplace for improved welding per-formance, drawing upon ESAB’sextensive experience and specialistknowledge of the production tech-nologies involved.

use of copper-free wires wheneverpossible to improve the safety ofthe workplace environment.

The new AristoRod range current-ly comprises OK AristoRod 12.50(EN G3Si/ER70S-6), OKAristoRod 12.57 (EN G2Si/ER70S-3) and OK AristoRod 12.63 (ENG4Si/ER70S-6). The range is avail-able on 18kg adapter-free basketspools and in environmentally recy-clable, octagonal cardboard drums,250 or 475kg MarathonPac. Theseare specifically suited for mecha-nised and robotised stations,because downtime for spool chang-ing is considerably reduced.

OK AristoRod - A NEW GENERATION OF COPPER-FREE WELDING WIRES FROM ESAB


A2 TRIPLETRAC, THREE-WHEELED SAW TRACTOR FORPRECISION JOINT TRACKINGESAB’s new A2 Tripletrac is athree wheel tractor developed forsuperior tracking during highlydemanding internal circumferentialwelding of large diameter cylindri-cal objects, using the submerged arcwelding (SAW) process.

Minimum internal diameter foroperation of Tripletrac is 1300 mm.Its key feature is the combinationof a steerable front wheel with posi-tioning of the welding head on thesame axis. This enables themachine to track the joint withsuperior precision.

Welding performance of Tripletracis similar to that of the highlyregarded four-wheel A2 Multitrac.The machine is suitable for use withESAB’s PEH or PEI process con-trollers, and is equipped for singlewire SAW as standard.

ESAB AUTOMATION DELIVERSCHAIN WELDING MACHINE TOKOREA.During February 2003, ESAB AB,Welding Automation delivered atype ZFKA 12 flash butt weldingmachine to Dai Han Anchor ChainMfg. Co. Ltd. in Korea, for the pro-duction of heavy chains. Dai Han isone of the biggest chain manufactur-ers in the world and a long-termESAB customer. ESAB’s first con-tract with Dai Han dates back to1978 and, since then, eight flash buttwelding machines, from size 5 up tosize 12, have been delivered.

WPS DATABASEOver the years, ESAB’s many sup-port services have developed innu-merable Welding Procedure Specifi-cations (WPS) for customers, world-wide. These are now being enteredinto an unrivalled database that canbe accessed by both ESAB’s techni-cal marketing teams and customers.This database comprises WPSes thathave proved successful in actual fab-rication welding at customers from avariety of industrial sectors or thathave resulted from applicationresearch.The database is accessible throughesab.com, under the section"Knowledge Centre", using theentry code "WPS:es", and a pass-word. To enhance the searchprocess, you will be asked for infor-mation such as process, type of steel,position and plate thickness.Subsequently, the database will tellyou when there are WPSes thatmatch your specific application.You will then be directed to yourlocal ESAB sales organisation forfurther information. In this way, ourspecialists will be able to verify thatthe suggested procedures can beused as they are, or need modifica-tion.

STAINLESS STEEL WORLDWINS AWS AWARD FOR ESABARTICLE ON THE THREEGORGES DAM PROJECTThe internationally renowned tech-nical magazine Stainless Steel Worldhas earned the AWS 2003 SilverQuail award for the best editorialcoverage on the subject of welding,published by magazines outside thefield of welding. The nominatedarticle, written by ESAB authorsLeif Karlsson, Nils Thalberg andJohn van den Broek, describes thehigh deposition welding of Francisturbine runners for the ThreeGorges dam project in China. Theaward was presented during the2003 AWS International Weldingand Fabrication Exposition and 84th

Annual Convention in Detroit,Michigan. The article was also pub-lished in Svetsaren 2002/2.

WELDING PROCESSESHANDBOOKThe Welding Processes Handbookis a concise, introductory handbookproviding detailed coverage of themost common welding processes.

The publication of this guide to weld-ing was originally prompted by adesire to provide an up-to-date refer-ence to the major applications ofwelding as they are used in industry.

The contents have been carefullyarranged so that it can be used as atextbook for European weldingcourses in accordance with guidelinesfrom the European WeldingFederation or International Instituteof Welding. Welding processes andequipment necessary for each pro-cess are described so that they applyto all instruction levels required.

The author, Klas Weman, has madea conscious effort to ensure thatboth the text and illustrative mate-rial is clear and arranged in a user-friendly way. He concentrates inparticular on providing a clear guideto the most important aspects.

Klas Weman is an engineer withgreat experience in the area ofwelding obtained both from hiswork at ESAB and as professor atRoyal Institute of Technology inStockholm.

Published by Woodhead PublishingLtd., Cambridge. 193 pages.

Contents:• Arc welding – an overview• Gas welding• TIG welding• Plasma welding• MIG/MAG welding• Metal arc welding with coated

electrodes• Submerged arc welding• Pressure welding methods• Other methods of welding• Cutting methods• Surface cladding methods• Mechanisation and robot welding• Soldering and brazing• The weldability of steel• Design of welded components• Quality assurance and quality

management• Welding costs


Kvaerner Masa Yards in Turku,Finland, owned by the industrialconglomerate Kvaerner ASA, isone of the world’s largest and mostmodern shipyards, designing andbuilding advanced cruise ships, pas-senger-car ferries and other techni-cally demanding vessels. On theirstiffener Twin/Triple* arc SAWwelding station, they use 37m longliners to feed OK Autrod 12.22wire from 450kg JumboMarathonPac. A world record toour best knowledge. We invite allour readers to beat this record anddeserve a special mentioning inSvetsaren.

Both sides of the stiffeners arewelded simultanuously onto huge22m plate fields. The portal isequipped with two hanging weldingcarriages with each two weldingheads. Per welding head three arcscan be ignited, so there is the possi-bility to have 12 arcs burning at thesame time. The welds are continu-ous or intermittent fillet welds witha throat thickness of 2.5-8mm andare deposited with a very high trav-el speed.

It stands to reason that arc distur-bances or feeding irregularities areunacceptable in such a highly effi-cient welding station and that anydowntime of the system is to beavoided. ESAB SAW wire, in thiscase OK Autrod 12.22 diameter 1.6or 2.0mm, fed from 450kg bulkpackaging is the ideal consumablefor this kind of high duty welding.

The special coiling technology usedby ESAB in the production ofMarathonPac ensures that thewires provide optimum anddependable feedability in greatlengths of liners and at high wirefeed speeds, and leave the weldinggun perfectly straight providingexactly positioned straight welds.No straightening devices are need-ed. The low friction of the wires inthe liner also provides excellent re-

strike properties which is veryimportant for intermittent welding. Last but not least, the downtime forspool changing, as frequentlyoccurring with standard 30kg wirespools, is brought back to anabsolute minimum by the use of450kg bulk packs, which stands fora major contribution to the efficien-cy of the welding station.

Kvaerner’s welding foreman, Mr.Sakari Saarenpää, confirms that hisfabrication enjoys all of the benefitsdescribed above, but he wanted tounderline one specific property." When we do intermittent welding,we have up to 7500 arc starts perday. Start defects are now min-imised. Also the positioning of thearc has improved a lot, resulting invery few weld defects. This, togeth-er with the drastically reduceddowntime for spool changing, hasimproved the productivity of thecomplete stiffener production linetremendously".

Mr Saarenpää’s team developed aceative solution to control long lin-ers when the welding carriage ismoving as far as 22 meters acrossthe plate field. They made the lin-ers roll in a channnel (Figures 2 and3) according to the principle of socalled "energy chains", a very com-mon model in electrical engineer-ing. Since the welding portal couldnot carry 5.4 tons of extraMarathonPac load, the bulk drumswere placed on the floor near thestation.

We declare the longest liner recordto be in the hands of KvaernerMasa Yards. Anyone usingMIG/MAG wire, cored wire orSAW wire from MarathonPac orJumbo MarathonPac is challengedto break it.

* Triple Arc is a further develop-ment of the Twin Arc process byMasa-Yards. There are three wiresconnected to one power source.

CONFERENCES

ESAB specialists will address lec-tures at the following conferences:

• American Welding Society 4thWeld Cracking: Causes & CuresConference - September 9 - 10,2003 New Orleans, LouisianaUSA

Tony Anderson, TechnicalManager AlcoTec Wire - CrackingIn Aluminum Alloys

• Joining of corrosion resistantmaterial, 2-4 October, 2003,Opatija, Croatia.

Leif Karlsson: The Synergic ColdWire (SCW) Submerged ArcWelding of Highly AlloyedStainless Steels.

• Stainless Steel World 2003Conference & Expo, 11-13November 2003, Maastricht,The Netherlands.

Leif Karlsson: The Synergic ColdWire (SCW) Submerged ArcWelding of Highly AlloyedStainless Steels.Leif Karlsson: ControllingSegregation in Ni-base Weld Metalsby Balanced Alloying.

• Fabtech International 2003Conference - November 16-19,2003 McCormick ConventionCenter Chicago, Illinois USA

Tony Anderson, TechnicalManager AlcoTec Wire - WeldingAluminum (2 Hour Presentation).

• ET´04 8th International alumini-um extrusion technology semi-nar, Kissimmee, Florida 18-21May 2004

Kari Erik Lahti: Wider Extrusionsat Lower Cost by Friction StirWelding.

USING MARATHONPAC WITH 37M LONG LINERS.

A WORLD RECORD?

By: Jussi Halonen, ESAB Oy, Finland.


ESAB’s commitment to the shipbuilding industry is as old as the

company itself. Today we are a leading supplier of complete cutting

and welding solutions.

Based on our knowledge and long experience we work closely

together with our customers to develop modern and productive

solutions for them. Our world wide presence means there is quali-

fied cutting and welding support available in almost every country

where shipbuilding and offshore construction take place. Your partner in welding and cutting

ESAB AB, Box 8004, SE-402 77 Göteborg, Sweden. Phone: +46 31 50 90 00, Fax: +46 31 50 93 90, Web: www.esab.com, E-mail: [email protected]

We started our company developing solutions for the shipbuilding industry.

And we still do.

Svetsaren, Esab AB, Marketing Communicationc/o P.O. Box 8086, 3503 RB Utrecht, The Netherlands

Tel. +31 30 248 5223. Fax. +31 30 241 1535Internet: http://www.esab.com

E-mail: [email protected]

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