BALL VALVE DOUBLE SIDE - MECPL...
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Coating improves Surface Wear Resistance on Ball & Gate Valves MEC THERMAL SPRAY FACILITIES COATING SYSTEMS FOR HVOF, PLASMA, FLAME SPRAY, ARC SPRAY & ROD SPRAY Tech. Bulletin#08/109.00 The use ofvalvesinmanyindustrialprocesseshasattracted more demands in terms of safe working s With these demands, the valve business has developed significantly over the last 10 years with respect to corrosionresistantmaterials,overlays&hardcoatings. In early days of ball valve manufacturing, there were many practising use like chrome plating on corrosion resistant substrates, nickel plating with associated heat treatment, stellites, and colmonoys. But each process had their limitations in the performance & properties,since the industrial acceptance of those processes were minimized. New stringent rules were implemented under Environmental Protection Agency in the last couple of decades. These ruleshavedrasticallylimitedthe amount of allowable hexavalent chromium ions, (carcinogenic), released during the hard chrome platingprocess. temperature, pressure, environmental working conditions and economic . New wear and corrosion resistant coatings have been developed and made it possible to increase the working envelop of valves, and fail free operation under the most extreme conditions, considerably improving the valve change overeconomics. The limitations of other conventional surface protective processes have thrown some light on the applications of thermalsprayforthesurfacewearresistanceofball&gate valves. Several organizations were setup to promote Thermal Spray, such as HVOF & Plasma Spray Technologies. Although the valve industry started utilizing the thermal spray coatings in the early days of its development, it only become more accepted and widespread in the early 80's once the associated costs become economically feasible. As the number of coated parts grew and the performance tracking proved its viability, more and more sceptics, including valve manufacturers, started to be convinced of its realbenefits. Working Environment of Valves Replacement of Hard Chrome Plating High Quality valves are used in special demanding environments and applications. The proper performance of these valves is many times critical to the whole process. The valves are frequently operated under the following extremeconditions: a) Fluidscontainingabrasiveparticles b) Corrosive fluids c) Operatingathightemperatures(>600°C) d) Operatingatpressuresover130MPa.
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Transcript of BALL VALVE DOUBLE SIDE - MECPL...
Coating improves Surface WearResistance on Ball & Gate Valves
MECTHERMAL SPRAY FACILITIESCOATING SYSTEMS FOR HVOF, PLASMA, FLAME SPRAY, ARC SPRAY & ROD SPRAY
Tech. Bulletin#08/109.00
The use ofvalvesinmanyindustrialprocesseshasattractedmore demands in terms of safe working
s With these demands, the valve business hasdeveloped significantly over the last 10 years with respectto corrosionresistantmaterials,overlays&hardcoatings.
In early days of bal l valvemanufacturing, there were manypractising use like chrome plating oncorrosion resistant substrates, nickelplat ing with associated heattreatment, stellites, and colmonoys.But each process had their limitationsin the performance & properties,sincethe industrial acceptance of thoseprocesses were minimized. Newstringent rules were implementedunder Environmental ProtectionAgency in the last couple of decades.These ruleshavedrasticallylimitedtheamount of allowable hexavalentchromium ions, (carcinogenic),released during the hard chromeplatingprocess.
temperature,pressure, environmental working conditions andeconomic .
New wear and corrosion resistant coatings have beendeveloped and made it possible to increase the workingenvelop of valves, and fail free operation under the mostextreme conditions, considerably improving the valvechange overeconomics.
The limitations of other conventional surface protectiveprocesses have thrown some light on the applications ofthermalspray forthesurfacewearresistanceofball&gatevalves. Several organizations were setup to promoteThermal Spray, such as HVOF & Plasma SprayTechnologies.
Although the valve industry started utilizing the thermalspray coatings in the early days of its development, it onlybecome more accepted and widespread in the early 80'sonce the associated costs become economically feasible.As the number of coated parts grew and the performancetracking proved its viability, more and more sceptics,including valve manufacturers, started to be convinced ofits realbenefits.
Working Environment of Valves
Replacement of Hard Chrome Plating
High Quality valves are used in special demandingenvironments and applications. The proper performanceof these valves is many times critical to the whole process.The valves are frequently operated under the followingextremeconditions:
a) Fluidscontainingabrasiveparticlesb) Corrosive fluidsc) Operating athightemperatures(>600°C)d) Operating atpressuresover130MPa.
COATINGS ARE PART OF VALVE DESIGN
COATING MATERIAL SELECTION
Carefulengineeringreviewoftheapplicationandselectionof coating material needs to be part of the valve designprocess.Referringtoexistingstandardsisdefinitely helpful,however it is not enough to guarantee continuousperformance.
The behaviour of a coating on a small size ball valve isentirely different to the performance of coating on a largediameter valve.The elastic deformation onthediameterofseat needs to be exactly accommodated by a flexiblecoating.
There are many choices of hard coatings available todayfor the valve industry. The pure ceramic materials, likeChrome Oxide, are generally used in the chemicalprocessing industry, whereas the carbides, like TungstenCarbide,aremainlyutilizedinthepetrochemicalandOil&Gas industries. Methods of applications will be selectedaccording to theirproperties&coatingmaterials.
The industry,boththemanufacturer andtheenduser,needto recognize that the coatings increase the life of thecomponent rather than it last forever. Once the valve is inoperation, the coating may be damaged by a variety ofmechanisms, such as chemical attack, thermal shock,erosion, wear or mechanical damage and its intendedfunctionalitywillbehampered.
The selection of coating material should always bereviewed against the specific application. The end usersoften make the mistake of generalizing their selection byproduct line, by particular plant area, or even worse, plantwide.
BALL VALVE COATING BY HVOF SYSTEM
METAL TO METAL TECHNOLOGY
An innovation from MEC which introduces a new surfacecoated ball and gate valves used in the petrochemicalindustry, will set new standards of wear resistance andreliability. Surface engineering developed at MEC hasproduced a hardcoating solution ofballandgate valves forMETAL TO METAL (MTM) seals, as typically used in the oiland petrochemicalindustries and forpower generation andmarine application.
MTM valves have very clear advantages over soft seatedvalves.
a) Abilitytooperateinawidetemperature range;fromcryogenictoveryhightemperatures.
b) Excellentcorrosion, wearandabrasive resistance.c) Firesafe&Extended(Service)LifeCycle.
The features of High Quality MTM Valvefeatures:
a) The valve will be tight, both at low orhighdifferentialpressures.
b) The valve hasahightightness efficiency inbothflowdirections.
c) Temperature, pressure and bearingforce fluctuations have no influenceontheseatperformance.
d) The valve remains tight, even whenhandlingfluids.
1. PERFECTFIT :
COATINGS ARE PART OF VALVE DESIGN
2. NOJAMMING
3. SMOOTH CONTROL
4. LOW TORQUE
5. LIFETIME
6. WIDE TEMPERATUREWORKINGRANGE
7. CORROSION,ABRASION&EROSIONRESISTANCE
8. ECONOMY
a) Valve jamming, caused by scaling and solids, arereduced toaminimum.
b) The restriction of Corrosion minimizes the jammingproblems.
a) The friction is regularized throughout the operationwindow.
b) Friction fluctuation were brought under control which istheenemyofpropervalvecontrol
a) Modern ball/seat surface materials show a lowtorque. A lower torque results in smaller actuators,savingcostsanddimensions
a) TheMTMseatshavealonglifetime(service)cycle
a) MTM Seats are able to operate reliable and troublefree in a wide temperature range, from cryogenic tohightemperatures
a) A good coating selection and a good knowledge ofthe working conditions will ensure the best possibleprotection against corrosion, abrasion and erosionproblems
a) Long lifetimesb) Low maintenancec) Reducechangeovertimeofspareparts.
COATING OF SMALLER DIA (1 INCH)BALL VALVES BY HIGH VELOCITY
LIQUID FUE SPRAY SYSTEM
The selection of coating material is very important factorand should always be reviewed against the specificapplication. The end users often make the mistake ofgeneralizing their selection by product line, by particularplant area, or even worse, plant wide. Few of the HVOFpowders which generally used for Ball Valve & Seat Ringcoating,are:
Amperit518 WC-Co88/12
Amperit556/588 WC-Co-Cr86/10/4
Amperit544 WC-Ni 88/12
Amperit529 WC-HasteloyC
Amperit584/588 CrC-NiCr75/25
Amperit551 WC-CrC-Ni73/20/7
Typical Coating Materials (Powders)
Typical Coating Processes
The MTM seal technologyapplies an HVOF (Gas /Liquid Fuel) thermal spraycoating to the metalsubstrate of the valvecomponents which arethen diamond ground andpolished to a super-finishfor a very intimate surfaceand tight fit betweencomponents.
This process gives a verysmooth wear-resistant anda b r a s i o n - r e s i s t a n c esurface, able to withstandthe highly abrasive andcorrosive fluids which flowthrough the valves atextreme pressure, and attemperature greater than600 deg.C.
During HVOF process, high noise level(>130 dBa) is generated. It is advisable to operate the system insound proof booth (Acoustic Room) which protects both personnel & environment. The figure Shownabove is a modernThermalSprayCellcompletewithRobot&TurnTable.
METALLIZING EQUIPMENT CO. PVT. LTD.E-101, M.I.A., Phase-II, Basni, Jodhpur-342005 (India)
Ph. : +91 291 2747601 Fax : 2746359E-Mail : [email protected] / [email protected]
Web : www.mecpl.com
Delhi Mumbai Bangalore Secunderabad09312890541 022-24934370 0 [email protected] [email protected] [email protected] [email protected]
CertifiedISO9001by ROBOT
SPRAYWATCH
MEMBER OF
A) Complete High Velocity Oxy-Fuel / Liquid Fuel Coating System on turnkey basis atcustomer site.
B) CarryoutcoatingJobatMECfactoryinJodhpur(India).
C) Develop specific coatings for special applications at our R&D Laboratory, approved byDepartmentof Scientific&IndustrialResearch,Govt.ofIndia.
Offers from MEC
A typical Modern Thermal Spray Room
