Thermatool-Application-Select.pdf

W o r k C o i l s I m p e d e r s F e r r i t e C a s i n g s J a w s & B l a d e s

Application and Selection Guide

Solid State Welder Work Coils General Information . . . . . . . . . . . . . . . . . . . Page 1

Solid State Welder Work Coils–Selection . . . . Page 4

Solid State Welder Coil Holders–Selection . . . Page 6

Vacuum Tube Welder Work Coils General Information . . . . . . . . . . . . . . . . . . . Page 7

Vacuum Tube Welder Work Coils–Selection . . Page 8

HF Welding Contacts . . . . . . . . . . . . . . . . . . . Page 9

Impeder Application and Selection . . . . . . . . . . Page 10

Impeders General Information . . . . . . . . . . . . . Page 12

Flow Through Impeders . . . . . . . . . . . . . . . . . . Page 13

Exposed Ferrite Impeders . . . . . . . . . . . . . . . . Page 14

Return Flow Impeders . . . . . . . . . . . . . . . . . . . Page 15

Integral Mandrel Impeders . . . . . . . . . . . . . . . . Page 16

Over Mandrel Impeders . . . . . . . . . . . . . . . . . . Page 17

Impeder Cluster Assembly . . . . . . . . . . . . . . . . Page 18

Impeder Casings . . . . . . . . . . . . . . . . . . . . . . . Page 19

Ferrite Grade 2006 Selection . . . . . . . . . . . . . . 0

Ferrite Grade 2006 General Information and Application . . . . . . . Page 23

Cutoff Blades . . . . . . . . . . . . . . . . . . . . . . . . . . Page 24

Cutoff Blades . . . . . . . . . . . . . . . . . . . . . . . . . . Page 25

Cutoff Jaws . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 26

Cutoff Jaws Ordering Information . . . . . . . . . . . Page 27

Suggested Technical Materials. . . . . . . . . . . . . Page 28

This application and selection guide has been developedto assist you in identifying, selecting and orderingThermatool work coils, contacts, impeders, impeder casings and ferrites, and cutoff jaws and blades.

The sections in this guide are color-coded to make it easyto find the information you need fast. The sections andtheir color codes are as follows:

Section I: Work Coils for Solid State and Vacuum Tube HF Welders

Section II: Contacts for HF Welders

Section III: Impeders, Casings and Ferrite

Section IV: Cutoff Jaws and Blades

Thermatool experts on applications, engineering andspare parts are always available to help you. For assistance, please call 203-468-4100 or fax at 203-468-4285.

Each section of this guide concludes with “How to Orderfrom Thermatool.” It defines the key information requiredto order work coils, impeders, casings, ferrite, jaws andblades. Typically, this includes tube diameter, material, mill direction and other important variables. Please refer tothis section to assist you in your selection and purchasingdecisions.

Thermatool has a team of specialists available to assistyou in selecting the appropriate ferrite, impeder, casingand/or work coil for your application. To contact this group,please call Thermatool at 203-468-4100 and ask for theSpare Parts Group or fax at 203-468-4285.

How to Use this Guide

How to Order from Thermatool

Table of Contents

Thermatool Application and Selection Guide

W o r k C o i l s I m p e d e r s F e r r i t e C a s i n g s J a w s & B l a d e s

Thermatool solid state welder work coils aredesigned and manufactured specifically for usewith Thermatool Solid State Welders with CFI2

Technology. They are available in three standardconfigurations: tubular coils (see figure 1), bandedcoils (see figures 2 and 3) and split coils (see figure 4). They are part of a system whichincludes the coil and the coil holder specificallyengineered to optimize the performance of thewelding system.

Tubular coils are constructed from high-conductivitycopper tubing and are available in single-turn,two-turn and three-turn configurations. They arerecommended for tube OD’s (outside diameter’s)from 13mm (0.5�) to 32mm (1.25�).

Banded coils are constructed from high-conductivitycopper and insulated with epoxy paint. They areavailable in single-turn and two-turn configurations.Because they are designed with greater radialclearance, alignment problems and arcing to thetube are greatly reduced.

Split coils are constructed of high-conductivitycopper material and include a spray-cooleddesign to ensure long life, easy maintenance and repair.

The high-voltage coils used with vacuum tubewelders usually do not work well with low-voltagesolid state welders. Thermatool has developed afamily of work coils designed to optimize solidstate HF welding.

For a particular tube-welding application, one type of coil will usually work better than another.Generally, the single-turn coil will work better withlarge mills operating at the small end of their tubediameter range, and the two-turn coil will workbetter with small mills producing at the high end oftheir tube diameter range.

Tube material will also affect the work coil design.Our most widely used coils are best for producingpipes or tubes made from low-carbon steel– themost common pipes and tubes produced. High-conductivity materials such as aluminum mayrequire different work coil designs. These may beobtained by contacting Thermatool CustomerService at 203-468-4100 and explaining yourapplication requirements.

For more information about work coil effectiveness,please contact Thermatool to request a copy ofthe Welder Set-up and Operation Workbookand/or the High Frequency Pipe & Tube WeldingHandbook.

Solid State Welder Work Coils – General Information

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Tubular CoilsTubular coils are made from high-conductivity coppertubing (0.250� (6mm) or 0.375� (10mm)) and are insulated with 0.065� Teflon tubing. They are designedto match the impedance of Thermatool solid statewelders and to optimize the output power of the HFsystem. They are painted bright orange for high visibility.

Single-Turn Banded CoilsThermatool single-turn banded coils are constructedfrom high-conductivity copper tubing and insulated withepoxy paint. They are recommended for tube OD’s from 2.375� (60mm) to 4.5� (114mm) with a radial clearance range from 0.375� (9.4mm) to 0.5� (13.4mm).

Solid State Welder Work Coils – General Information

Fig. 1 Tubular Coil with tubular terminations.

Fig. 2 Single-Turn Banded Coil with tubular terminations.

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Multi-Turn Banded CoilsThermatool multi-turn banded coils are constructed of copper bands with brazed cooling tubes. They are insulated with epoxy paint and finished in brightorange for high visibility. They are recommended fortube OD’s from 0.625� (16mm) to 2.25� (57mm), andhave a nominal clearance range from 0.25� (6.0mm)to 0.33� (8.4mm).

Split CoilsThermatool work coils with split construction aremade from durable copper and are designedwith a spray-cooled system to ensure long life,and easy maintenance and repair. All split coilsare finished in bright orange for high visibilityand safety.

Fig. 3 Multi-Turn Banded Coil with tubular terminations.

Fig. 4 Split Coil with flange terminations.

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Solid State Welder Work Coils for Small Diameter Tubes (standard design)

Tube Outside Dia.Maximum

mm inch

Coil ID

mm

Coil Length(overall)

mm Turns Thermatool Part Number

for left-to-right mill for right-to-left mill

CoilType

13 0.5 19 19 2 tubular WL0025-005LH WL0025-005RH




16 0.625 26 55 2 banded WL0210-001LH WL0210-001RH

22 0.875 32 55 2 banded WL0210-002LH WL0210-002RH

29 1.125 40 73 2 banded WL0210-003LH WL0210-003RH

32 1.25 45 73 2 banded WL0210-004LH WL0210-004RH

38 1.5 51 87 2 banded WL0210-005LH WL0210-005RH

44 1.75 57 103 2 banded WL0210-006LH WL0210-006RH

51 2.0 64 127 2 banded WL0210-007LH WL0210-007RH

57 2.25 70 127 2 banded WL0210-008LH WL0210-008RH

64 2.5 80 47 1 banded WL0029-002 WL0029-002

76 3.0 90 47 1 banded WL0029-003 WL0029-003

79 3.125 95 47 1 banded WL0029-004 WL0029-004

89 3.5 105 47 1 banded WL0029-005 WL0029-005

102 4.0 120 67 1 banded WL0029-006 WL0029-006

114 4.5 140 76 1 banded WL0029-007 WL0029-007

CHART A

How to Order Solid State Welder Work Coils

Use chart A to identify the work coils for tubes between 13mm (0.5�) and 114mm (4.5�)and chart B for tubes between 60mm (2.375�) and 326mm (12.9�). Follow these steps:

1. Determine the outside diameter (OD) of the product to be produced.

2. Using chart A and/or chart B, find the “Maximum tube OD” (in column 1) that is closestto the OD of the product to be produced.

3. Follow the line over to the columns on the far right titled “Thermatool Part Number.”Then select the part number that fits your mill configuration (left to right or right to left).

For prices, call Thermatool spare parts at 203-468-4100 or fax at 203-468-4285.

Note: All Thermatool coils and coil holders have a part number stamped on them. Please look for the part numberto speed up the process of ordering and receiving new solid state welder work coils and coil holders.

Solid State Welder Work Coils – Selection

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How to Order Solid State Welder Work Coils

The information required to order a solid state welder work coil follows:

1. The diameter and material of the tube to be welded.2. Coil termination type (either tubular or flange).3. Mill direction (left to right or right to left– from the operator’s station).4. Coil type (tubular, banded or split).5. Number of turns.6. Cooling type (internal or spray).7. Coil holder type (tubular termination or flange termination).


Note: All Thermatool coils and coil holders have a part number stamped on them. Please look for the part number to speed up the process of ordering and receiving new solid state welder work coils and coil holders.

Solid State Welder Work Coils for Medium and Large Diameter Tubes (standard design)

Outside Tube Dia.Maximum

mm inch

Outside Tube Dia.Minimum

mmCoil ID

mm

Coil Length

mm Turns Thermatool

Part NumberCoilType

54 60 2.375 75 47 1 banded WL0158-001

60 70 2.750 85 47 1 banded WL0158-002

71 79 3.125 95 47 1 banded WL0158-003

80 89 3.500 105 47 1 banded WL0158-004

90 99 3.750 115 76 1 split WL0193-001

94 101 4.000 125 76 1 split WL0193-002

102 115 4.500 140 100 1 split WL0193-003

116 139 5.500 160 120 1 split WL0193-004

140 155 6.125 175 135 1 split WL0193-005

156 168 6.625 190 165 1 split WL0193-006

168 185 7.250 215 210 1 split WL0318-001

186 207 8.150 240 240 1 split WL0318-002

208 227 9.000 260 250 1 split WL0318-003

228 239 9.500 275 210 1 split WL0318-004

240 259 10.200 290 290 1 split WL0318-005

260 277 10.900 315 315 1 split WL0319-001

278 305 12.000 345 345 1 split WL0319-002

304 315 12.400 360 400 1 split WL0319-003

315 326 12.900 375 450 1 split WL0319-004

CHART B

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Thermatool coil holders are made of durable copper material and are designed to properlyposition the work coil in the weld area. They areengineered to optimize “vee” length and provide alow inductance connection for “zero” voltage drop.

Thermatool type I (tubular termination) coil holders eliminate arcing at the lead assembly andensure properly matched work loads.

Thermatool type II (flange termination) coil holdersare designed for higher power-current transfer,enhanced mechanical support for work coils, and better electrical connection between the holderand the work coil.

How to Order Solid State Welder Coil Holders

Solid state welder coil holders are available in two basic types (Type I and Type II); Type I coil holders are used with work coils with tubular terminations. Type II coil holdersare used with work coils with flange terminations.

Type I coil holders are available in three lengths:1. WL 0365-001 is the standard length coil holder (190mm).2. WL 0365-002 is 50mm longer than the standard coil holder (240mm).3. WL 0365-003 is 100mm longer than the standard coil holder (290mm).

Type II coil holders are available in two widths and in versions for left to right mills andright to left mills:1. WL 0331-001 is the standard width coil holder for left to right mills (75mm).2. WL 0331-002 is the standard width coil holder for right to left mills (75mm).3. WL 0177 is the extended width coil holder for left to right mills (190mm).4. WL 0161 is the extended width coil holder for right to left mills (190mm).


Fig. 5 Type I coil holder.

Fig. 5 Use with work coils withtubular terminations.

Solid State Welder Coil Holders

widthFig. 6 Type II coil holder.

Fig. 5 Use with work coils withflange terminations.

Fig. 4-2 Offset coil - both leads in-line with one coil end turn.

Fig. 4 In-line co with coil e

Fig. 8 Offset coil– leads in-line with one coil end turn.

Fig. 7 In-line coil– leads in-line with coil end turns.

Fig. 9 Shell type coil design for larger diameter pipe permits increased coil length for single-turn coil. Split construction facilitates coil changeover.

Vacuum Tube Welder Work Coils – General Information

Thermatool induction welding coils are available in four types: In-Line (Figure 7), Offset (Figure 8),Shell (Figure 9) and Banded (Figure 10).

In-line coils have 1/2� diameter hard-drawn copperleads and are recommended for use with vacuumtube welders. Offset coils have 3/8� diameterleads, and are intended to be used with dual output, older vacuum tube type welders. Shell and banded type coils are used where one- ortwo-turn coils are required on large size pipe production. These coil types permit attaining therequired coil length (CL) with one or two turns.They also provide split coil construction whichallows changing coils without rethreading the mill.

Fig. 10 Banded type coil achieves increased coil length with few turns. Split coil construction is shown here.

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8

10 .39 15 .59 4 C1071-1D

12.5 .49 17.5 .68 4 C1071-2D

15 .59 20 .78 4 C1071-3D

20 .78 27 1.05 4 C1071-4D

25 .98 34 1.33 3 C1071-5D

30 1.17 40 1.56 3 C1071-6D

35 1.37 45 1.76 3 C1071-7D

40 1.56 52 2.03 3 C1071-8D

50 1.95 63 2.46 3 C1071-9D

60 2.34 75 3.93 3 C1071-10D

75 2.93 90 3.52 3 C1071-11D

90 3.52 110 4.30 3 C1071-12D

110 4.30 130 5.08 3 C1071-13D

130 5.08 150 5.86 3 C1071-14D

150 5.86 170 6.64 3 C1071-15D

Vacuum Tube Work Coils

Tube SizeOutside Dia.

mm inches

Coil SizeInside Dia. Turns

mm inches TurnsCoil

Part Number

All welder work coils are made from high-conductivity copper and are wound clockwise (for right to left mill direction) unless specified otherwise.

CHART C

How to Order Vacuum Tube Welder Work Coils

To select and order vacuum tube welder work coils, the following information is required:1. The model number of the welder (i.e. VT 80, TI 100, TMI 100, etc.).2. The outside diameter of the tube or pipe being produced.

Use chart C above to identify the appropriate welder work coil for TI and TMI generationvacuum tube welders.

1. Identify the outside diameter of the product to be produced.

2. Using chart C, find the outside diameter (in column 1) that is closest to the OD of theproduct to be produced.

3. Follow the line over to the column on the far right titled “Coil part number”, select the part number for the coil.

For prices, call Thermatool at 203-468-4100 or fax at 203-468-4285.

Vacuum Tube Welder Work Coils – Selection

Thermatool HF Welding Contacts

Standard TypesTwo types of contacts are standard in Thermatoolhigh frequency tube and pipe welding equipment.They are shown below. Figure 11 is of an extendednose contact tip, and figure 12 is a straight contact tip.

Standard contacts are used in most tube contactwelding installations. However, when welding sometypes of nonferrous materials, the contacts may haveto touch the tube edges closer to the squeeze rollsthan is feasible with these two types. Extended nosecontacts are shaped as the name implies, and thetips can extend farther into the space between thesqueeze rolls without interference than can the othertypes. This enables a shorter vee-length to be used.

Contact ConstructionThe body of the contact is copper, with internal coolingwater passages which are drilled close to the tips and the contact material. They are attached to thesecondary leads or to the adapters by means ofscrews. The water inlet and outlet to each contact isthrough an “O” ring connection to the lead or theadapter. There are no hose connections on the contacts.

Contact Tip MaterialThe tip, which makes direct contact to the tube, ischosen for its current-carrying and wearing qualities,and the material being welded. These tips arebrazed to the forward underside of the contact body.Several different types of materials are used.

It should be noted that the use of copper contact tipscan result in copper deposition from arc burns. Thecopper can permeate the steel grain boundaries andcause embrittlement. This is of concern when thepipe being welded is to be used for transportinghydrocarbons with higher H2S contents. The choiceof non-copper contacts such as tungsten or tungsten-silver may prevent the problem.

Contact Tip SizeContact tips are furnished in various standard sizes.The optimum size to use in a given situation dependsupon a number of factors. For small diameter tubes itis desirable, for instance, that the contact width beas narrow as possible. This is to reduce even furtherthe current which flows around the back of the strip.With larger tubes it is frequently desirable to use awider contact surface so as to reduce unit pressureand mechanical wear. The tip which is furnished hasrectangular cross sections, so that they can bebrazed to the contact body edgewise or flatwise. Theoptimum tip length also depends somewhat upon theparticular situation. Thermatool customer service canrecommend the proper size and the method ofmounting for each installation.

Fig. 11 Extended Nose Contact Tip - A.

Fig. 12 Straight Contact Tip - B.

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How to Order Thermatool HF Welding Contacts

To select and order Thermatool contacts, the following information is required:

1. The model number of the welder (i.e. VT 80, TC 100, TMC 100, CFC 100).

2. The output power rating of the welding system (100kw, 150kw, etc.).

3. The serial number of the welding unit.

Many different generations of Thermatool contact welding equipment havebeen installed. To be certain of selecting the right contacts for your equipment, please call Thermatool’s spare parts group for assistance at203-468-4100 or fax at 203-468-4285.

Pricing information for HF welding contacts is available by contacting theThermatool spare parts group.

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Tube OutsideDiameter

Coil InsideDiameter

CL = CID

Direction of Travel

C CIDOD

CLCoil Length

A

1/8 in.

BImpeder

E

Fig. 13 Proper size and position of the coil and ferrite are essential for efficient performance. Impeder length is dependent on specific mill characteristics (seam guide, support structure, etc.).

Thermatool Impeders –Application and Selection

For maximum efficiency, impeders must be properlyselected. Thermatool impeders have the ferriteplaced 1/2� from the end of the fiberglass tube, sothe end of the impeder should be 5/8� beyond thecenterline of the weld rolls.

Referring to Figure 13, Dimension A will depend onthe design of the mill and weld roll diameter andshould be kept to a minimum, preferably not exceeding the tube diameter (OD).

The impeder diameter (Dimension C) should be aslarge as possible for maximum efficiency, but in practice its size is limited to approximately 75% ofthe tube diameter (OD). In general, the larger thediameter of the ferrite, the faster the weld speed.

The cross section of ferrite required for welding for larger pipe sizes is determined by actual vee-length,speed and frequency.

As a rule of thumb, the impeder length should beequal to Dimension A (vee-length) plus DimensionCL (coil length) plus Dimension E (B = A + CL + E).

It is recommended that Dimension E be greater thanDimension A (optional is E = 2A).

As a general rule, the impeder length (Dimension B)should be at least equal to 3.5 times the length ofthe coil (CL), or 3.5 times the coil inside diameter(CID) (i.e. B = 3.5 x CID = 3.5 x CL).

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0.500� 8mm (0.312�)

0.563� 9mm (0.350�)

0.625� 10mm (0.390�)

0.688� 11mm (0.430�)

0.750� 12mm (0.468�)

0.813� 13mm (0.512�)

0.875� 14mm (0.550�)

0.938� 14mm (0.550�)

1.000� 16mm (0.625�)

1.063� 16mm (0.625�)

1.125� 16mm (0.625�)

1.188� 19mm (0.750�)

1.250� 19mm (0.750�)

1.313� 22mm (0.875�)

1.375� 22mm (0.875�)

1.438� 22mm (0.875�)

1.500� 25mm (0.977�)

1.563� 25mm (0.977�)

1.625� 25mm (0.977�)

1.688� 25mm (0.977�)

1.750� 1.062�

1.813� 1.062�

1.875� 1.187�

1.938� 1.187�

2.000� 1.312�

2.063� 1.312�

2.125� 1.312�

2.188� 1.312�

2.250� 1.500�

2.313� 1.500�

CHART DRecommended Impeder Sizes for Induction Welding

Inside Dia. Impeder

Outside Dia. Inside Dia. Impeder

Outside Dia.Inside Dia. Impeder

Outside Dia.

2.375� 1.500�

2.438� 1.500�

2.500� 1.750�

2.563� 1.750�

2.625� 1.750�

2.688� 1.750�

2.750� 1.750�

2.813� 2.000�

2.875� 2.000�

2.938� 2.000�

3.000� 2.000�

3.063� 2.000�

3.125� 2.000�

3.188� 2.000�

3.250� 2.250�

3.313� 2.250�

3.375� 2.250�

3.438� 2.250�

3.500� 2.250�

3.563� 2.250�

3.625� 2.250�

3.688� 2.250�

3.750� 2.250�

3.813� 2.500�

3.875� 2.500�

3.938� 2.500�

4.000� 2.500�

4.063� 2.500�

4.125� 2.500�

4.188� 2.500�

4.250� 2.500�

4.313� 2.500�

4.375� 2.500�

4.438� 2.500�

4.500� 2.500�

4.563� 3.000�

4.625� 3.000�

4.688� 3.000�

4.750� 3.000�

4.813� 3.000�

4.875� 3.000�

4.938� 3.000�

5.000� 3.000�

5.063� 3.000�

5.125� 3.000�

5.188� 3.000�

5.250� 3.000�

5.313� 3.000�

5.375� 3.000�

5.438� 3.000�

5.500� 3.000�

5.563� 3.500�

5.625� 3.500�

5.688� 3.500�

5.750� 3.500�

5.813� 3.500�

5.875� 3.500�

5.813� 3.500�

5.875� 3.500�

6.000� 3.500�

Note: All dimensions are in inches except where noted.

How to Order Thermatool Impeders

The impeder is usually a ferrite rod inside a fiberglass or quartz shield. The purpose of the shield is to protect theferrite from damage and to channel the cooling water around the ferrite. However, it is the ferrite that controls themagnetic field generated by the work coil. Hence the dimensions of the ferrite–not the dimensions of the shield–affect the results of the process.

Impeders should be chosen and positioned according to the following guidelines:

1. The ferrite’s diameter should be as large as is practical. In general, its diameter should be 75% of the tube ID.2. In large pipe or tube fabrication, where multiple ferrite rods are used or in cases where internal scarfing devices

limit placement of the ferrite within the tube, the ferrite should be placed as close to the vee as possible.3. The length of the impeder should be chosen so that the “head roll” end of the ferrite (not the end of the housing)

extends approximately 0.125�-0.25� beyond the apex of the vee (past the head rolls), and the other end of theferrite extends approximately two tube diameters up-stream from the work coil.

4. Identify the inside diameter of the pipe or tube to be produced.5. Identify the optimal condition inside the tube during production (can it be wet, or should it be kept dry?)6. ID scarfing (is ID scarfing applied?)


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A

B

C

D

Direction of Travel

All Thermatool impeders are designed and manufactured to meet Thermatool’s stringent originalequipment specifications. They use Thermatool ferritegrade 2006 material which is specifically formulatedfor induction welding. This requires a combination ofhigh saturation flux density, low electrical and magnetic losses and high permeability.

The Impeder’s RoleRegardless of the type of equipment used for pipeand tube welding, the fundamental objective is toapply power or electrical energy to edges of theformed tube. The edges are sufficiently heated suchthat when squeezed together, a forged weld will result.With HF induction welding, the high frequency currentis “induced” in the formed tube by a coil which surrounds, but does not touch, the tube, hence thename “induction” welding. It is the heat generated bythe current flow along one edge of the “vee” ADC(Figure 14) to the squeeze point, and back along theother edge, which generates the heat in the weldzone.

In HF induction welding the objective is to route asmuch of the current as possible along the strip edgesADC (Figure 14) which are to be welded. Some of the current will have the tendency to flow around the internal surface, thus reducing current and the heat atthe weld point. The impeder is used to increase theimpedance of the ID path (ABC), forcing the current toflow along the strip edges (ADC) maximizing the heatavailable for the welding process. The greater theimpedance, the more efficient the welding operationwill be.

The role of the impeder in the HF induction weldingprocess cannot be over-emphasized because of theimpact it can have on production rates and weld quality.

Ferromagnetic MaterialsIn recent years, the degree of sophistication of customizing grades of ferrite to welding applicationshas begun to pay off in increased productivity.

HF induction welding initially was developed in the1950’s when the only ferrite rods available were the Q body (nickel-zinc) materials. Since then, improvedtechnology has led to the use of H body (manganesezinc) materials which in conjunction with recent welderdesign developments, has resulted in a quantum leapin productivity.

Today, impeder ferrites are created for and usedexclusively in HF induction welding. They possesshigh magnetic saturation coupled with high curie temperatures to extend their useful operating range in pipe and tube applications.

Fig. 14 In induction welding, the high frequency magnetic field from the coil induces an alternating current in the outsidesurface of the open seam tube. The current can takeeither of two parallel return paths: in the vee (ADC) oraround the inside surface of the tube (ABC).

Thermatool Impeders – General Information

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Flow Through ImpedersFlow through impeders are the most widely used of alltypes. Thermatool’s design uses ferrite having longitudinalslots for additional cooling. Since the performance of allferromagnetic materials is a function of temperature, it iscritically important to keep the core as cool as possible.All of our impeders have been carefully engineered toensure that adequate cooling is provided under all normal operating conditions.

These impeders consist of one or more ferrite coresinside a synthetic resin-bonded fiberglass tube. A standardflare fitting is epoxied and pinned into one end of thetube, and a retaining collar is fitted to the opposite end of the tube. Coolant enters through the flare fitting, andafter cooling the ferrite is discharged just beyond the weldpoint. The impeders are designed such that a pressure of40 PSI (275 kPa) will ensure an adequate flow of coolant,under all but the most extreme welding conditions.

Flow through impeders are available with three differenttypes of outer casing material.

Coupling Casing

Ferrite

Coolant Passage

Fig. 15 Standard flow through impeder.

PartNumber

Diameter (mm)

Diameter (in.) Type Thread

Coupling

Epoxyglass Casing (inch sizes)FTE-0250-XXX 6.4 0.250 1/4� Solder 1/4�-28FTE-0313-XXX 7.9 0.313 1/4� Solder 1/4�-28FTE-0375-XXX 9.5 0.375 1/4� Solder 1/4�-28FTE-0438-XXX 11.1 0.438 1/4� Solder 1/4�-28FTE-0500-XXX 12.7 0.500 1/4� Flare 7/16�-20FTE-0563-XXX 14.3 0.563 1/4� Flare 7/16�-20FTE-0625-XXX 15.9 0.625 1/4� Flare 7/16�-20FTE-0688-XXX 17.5 0.688 1/4� Flare 7/16�-20FTE-0750-XXX 19.1 0.750 1/4� Flare 7/16�-20FTE-0813-XXX 20.6 0.813 1/4� Flare 7/16�-20FTE-0875-XXX 22.2 0.875 1/4� Flare 7/16�-20FTE-0938-XXX 23.8 0.938 1/4� Flare 7/16�-20FTE-1000-XXX 25.4 1.000 1/4� Flare 7/16�-20FTE-1125-XXX 28.6 1.125 3/8� Flare 5/8�-18FTE-1250-XXX 31.8 1.250 3/8� Flare 5/8�-18FTE-1375-XXX 34.9 1.375 1/2� Flare 3/4�-18FTE-1500-XXX 38.1 1.500 1/2� Flare 3/4�-16

Epoxyglass Casing (metric sizes)FTE-12-XXX 12 0.472 1/4� Solder 1/4�-28FTE-14-XXX 14 0.551 1/4� Flare 7/16�-20FTE-15-XXX 15 0.591 1/4� Flare 7/16�-21FTE-16-XXX 16 0.630 1/4� Flare 7/16�-22

Silglass Casing (inch sizes)FTS-0688-XXX 17.5 0.688 1/4� Flare 7/16�-20FTS-0750-XXX 19.1 0.750 1/4� Flare 7/16�-20FTS-0813-XXX 20.6 0.813 1/4� Flare 7/16�-20FTS-0875-XXX 22.2 0.875 1/4� Flare 7/16�-20FTS-0938-XXX 23.8 0.938 1/4� Flare 7/16�-20FTS-1000-XXX 25.4 1.000 1/4� Flare 7/16�-20FTS-1063-XXX 27.0 1.063 3/8� Flare 5/8�-18FTS-1188-XXX 30.2 1.188 3/8� Flare 5/8�-18FTS-1313-XXX 33.3 1.313 1/2� Flare 3/4�-16FTS-1500-XXX 38.1 1.500 1/2� Flare 3/4�-16FTS-1750-XXX 44.5 1.750 1/2� Flare 3/4�-16FTS-2000-XXX 50.8 2.000 5/8� Flare 7/8�-14FTS-2250-XXX 57.2 2.250 5/8� Flare 7/8�-14FTS-2500-XXX 63.5 2.500 5/8� Flare 7/8�-14FTS-2750-XXX 69.9 2.750 5/8� Flare 7/8�-14FTS-3000-XXX 76.2 3.000 1� FPT 1�-11-1/2FTS-3500-XXX 88.9 3.500 1� FPT 1�-11-1/2FTS-4000-XXX 101.6 4.000 1� FPT 1�-11-1/2FTS-4500-XXX 114.3 4.500 1� FPT 1�-11-1/2FTS-5000-XXX 127.0 5.000 1� FPT 1�-11-1/2FTS-5500-XXX 139.7 5.500 1� FPT 1�-11-1/2FTS-6000-XXX 152.4 6.000 1� FPT 1�-11-1/2

Silglass Casing (metric sizes)FTS-10-XXX 10 0.394 1/4� Solder 1/4�-28FTS-12-XXX 12 0.472 1/4� Flare 7/16�-20FTS-14-XXX 14 0.551 1/4� Flare 7/16�-20FTS-16-XXX 16 0.630 1/4� Flare 7/16�-20

PartNumber

Diameter (mm)


Coupling

Ferroglass Casing (metric sizes)FTF-05-XXX 5 0.197 1/4� Solder 1/4�-28FTF-07-XXX 7 0.256 1/4� Solder 1/4�-28FTF-08-XXX 8 0.315 1/4� Solder 1/4�-28FTF-09-XXX 9 0.354 1/4� Solder 1/4�-28FTF-10-XXX 10 0.394 1/4� Solder 1/4�-28FTF-11-XXX 11 0.433 1/4� Solder 1/4�-28FTF-12-XXX 12 0.472 1/4� Flare 7/16�-20FTF-13-XXX 13 0.512 1/4� Flare 7/16�-20FTF-14-XXX 14 0.551 1/4� Flare 7/16�-20FTF-15-XXX 15 0.591 1/4� Flare 7/16�-20FTF-16-XXX 16 0.630 1/4� Flare 7/16�-20FTF-17-XXX 17 0.669 1/4� Flare 7/16�-20FTF-18-XXX 18 0.709 1/4� Flare 7/16�-20FTF-19-XXX 19 0.748 1/4� Flare 7/16�-20FTF-20-XXX 20 0.787 1/4� Flare 7/16�-20FTF-21-XXX 21 0.827 1/4� Flare 7/16�-20FTF-22-XXX 22 0.866 1/4� Flare 7/16�-20FTF-23-XXX 23 0.906 1/4� Flare 7/16�-20FTF-24-XXX 24 0.945 1/4� Flare 7/16�-20FTF-25-XXX 25 0.984 1/4� Flare 7/16�-20FTF-28-XXX 28 1.102 1/4� Flare 7/16�-20FTF-32-XXX 32 1.260 3/8� Flare 5/8�-18FTF-34-XXX 34 1.339 3/8� Flare 5/8�-18FTF-38-XXX 38 1.496 1/2� Flare 3/4�-16

CHART ETypical Flow Through Impeder Diameter

and Coupling Sizes

• Flow through impeders come in lengths of 9�, 13�, 17�, 25�, and 33�.

• Longer length and larger diameters as well as many special configurations are available.

14

Exposed ferrite impeders use a method of assembly inwhich the ferrite is attached directly to the coolant inlet,so that the casing serves no structural purpose and isonly used to direct the coolant around the ferrite. Thisovercomes the need for a retaining plug or pin at theexit end of the impeder and permits the ferrite to extendbeyond the casing. The laminar flow of coolant past theferrite immediately washes away any hot metal particlesthat may be ejected from the weld zone, preventingdamage to the impeder.

A secondary advantage of this type of impeder is thatsince there is no casing present at the narrowest part ofthe tube (right at the weld point), a larger-than-normalimpeder may generally be used, with a correspondingincrease in weld speed per kilowatt.

Exposed ferrite impeders are ideally suited for weldinghot rolled steel strip, aluminized or pre-galvanized strip,stainless steel and other difficult materials. They arealso the best choice for air- or gas-cooled applications.

Coupling Casing

Fluted Ferrite

Exposed Ferrite Impeders

Fig. 16 Exposed ferrite impeder.

PartNumber

Diameter (mm)


Coupling

Ferroglass Casing (metric sizes)EFF-07-XXX 7 0.256 1/4� Solder 1/4�-28EFF-08-XXX 8 0.315 1/4� Solder 1/4�-28EFF-09-XXX 9 0.354 1/4� Solder 1/4�-28EFF-10-XXX 10 0.394 1/4� Solder 1/4�-28EFF-11-XXX 11 0.433 1/4� Solder 1/4�-28EFF-12-XXX 12 0.472 1/4� Flare 7/16�-20EFF-13-XXX 13 0.512 1/4� Flare 7/16�-20EFF-14-XXX 14 0.551 1/4� Flare 7/16�-20EFF-15-XXX 15 0.591 1/4� Flare 7/16�-20EFF-16-XXX 16 0.630 1/4� Flare 7/16�-20EFF-17-XXX 17 0.669 1/4� Flare 7/16�-20EFF-18-XXX 18 0.709 1/4� Flare 7/16�-20EFF-19-XXX 19 0.748 1/4� Flare 7/16�-20EFF-20-XXX 20 0.787 1/4� Flare 7/16�-20EFF-21-XXX 21 0.827 1/4� Flare 7/16�-20EFF-22-XXX 22 0.866 1/4� Flare 7/16�-20EFF-23-XXX 23 0.906 1/4� Flare 7/16�-20EFF-24-XXX 24 0.945 1/4� Flare 7/16�-20EFF-25-XXX 25 0.984 1/4� Flare 7/16�-20EFF-28-XXX 28 1.102 1/4� Flare 7/16�-20EFF-32-XXX 32 1.260 3/8� Flare 5/8�-18EFF-38-XXX 38 1.496 1/2� Flare 3/4�-16

CHART FTypical Exposed Ferrite Impeder Diameter

and Coupling Sizes

PartNumber

Diameter (mm)


Coupling

Epoxyglass Casing (inch sizes)EFE-0250-XXX 6.4 0.250 1/4� Solder 1/4�-28EFE-0313-XXX 7.9 0.313 1/4� Solder 1/4�-28EFE-0375-XXX 9.5 0.375 1/4� Solder 1/4�-28EFE-0438-XXX 11.1 0.438 1/4� Solder 1/4�-28EFE-0500-XXX 12.7 0.500 1/4� Flare 7/16�-20EFE-0563-XXX 14.3 0.563 1/4� Flare 7/16�-20EFE-0625-XXX 15.9 0.625 1/4� Flare 7/16�-20EFE-0688-XXX 17.5 0.688 1/4� Flare 7/16�-20EFE-0750-XXX 19.1 0.750 1/4� Flare 7/16�-20EFE-0813-XXX 20.6 0.813 1/4� Flare 7/16�-20EFE-0875-XXX 22.2 0.875 1/4� Flare 7/16�-20EFE-0938-XXX 23.8 0.938 1/4� Flare 7/16�-20EFE-1000-XXX 25.4 1.000 1/4� Flare 7/16�-20EFE-1125-XXX 28.6 1.125 3/8� Flare 5/8�-18EFE-1250-XXX 31.8 1.250 3/8� Flare 5/8�-18EFE-1375-XXX 34.9 1.375 1/2� Flare 3/4�-18EFE-1500-XXX 38.1 1.500 1/2� Flare 3/4�-16

Epoxyglass Casing (metric sizes)EFE-12-XXX 12 0.472 1/4� Solder 1/4�-28EFE-14-XXX 14 0.551 1/4” Flare 7/16�-20EFE-15-XXX 15 0.591 1/4� Flare 7/16�-21EFE-16-XXX 16 0.630 1/4� Flare 7/16�-22

Silglass Casing (inch sizes)EFS-0688-XXX 17.5 0.688 1/4� Flare 7/16�-20EFS-0750-XXX 19.1 0.750 1/4� Flare 7/16�-20EFS-0813-XXX 20.6 0.813 1/4� Flare 7/16�-20EFS-0875-XXX 22.2 0.875 1/4� Flare 7/16�-20EFS-0938-XXX 23.8 0.938 1/4� Flare 7/16�-20EFS-1000-XXX 25.4 1.000 1/4� Flare 7/16�-20EFS-1063-XXX 27.0 1.063 3/8� Flare 5/8�-18EFS-1188-XXX 30.2 1.188 3/8� Flare 5/8�-18EFS-1313-XXX 33.3 1.313 1/2� Flare 3/4�-16EFS-1500-XXX 38.1 1.500 1/2� Flare 3/4�-16EFS-1750-XXX 44.5 1.750 1/2� Flare 3/4�-16EFS-2000-XXX 50.8 2.000 5/8� Flare 7/8�-14EFS-2250-XXX 57.2 2.250 5/8� Flare 7/8�-14EFS-2500-XXX 63.5 2.500 5/8� Flare 7/8�-14EFS-2750-XXX 69.9 2.750 5/8� Flare 7/8�-14EFS-3000-XXX 76.2 3.000 1� FPT 1�-11-1/2EFS-3500-XXX 88.9 3.500 1� FPT 1�-11-1/2EFS-4000-XXX 101.6 4.000 1� FPT 1�-11-1/2EFS-4500-XXX 114.3 4.500 1� FPT 1�-11-1/2EFS-5000-XXX 127.0 5.000 1� FPT 1�-11-1/2EFS-5500-XXX 139.7 5.500 1� FPT 1�-11-1/2EFS-6000-XXX 152.4 6.000 1� FPT 1�-11-1/2

Silglass Casing (metric sizes)EFS-10-XXX 10 0.394 1/4� Solder 1/4�-28EFS-12-XXX 12 0.472 1/4� Flare 7/16�-20EFS-14-XXX 14 0.551 1/4� Flare 7/16�-20EFS-16-XXX 16 0.630 1/4� Flare 7/16�-20

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Return Flow Impeders (Figure 17) are recommendedwhen it is important to keep the inside of the weldedtube dry. Impeder coolant enters and exits the impederthrough a special coaxial coupling and is either discharged outside the tube or re-circulated.

Return flow impeders have coaxial inlet and outlettubes and require the use of a special coaxial coupling(Figure 17). Four sizes of couplings are available toaccommodate impeders from 10mm (0.391�) to 76mm(3�) in diameter. These couplings are supplied withsuitable coaxial attachments on one side and terminatewith two short tubes which may be extended to suitthe mill on which they will be used.

All Return flow impeders are provided with 1/2� thickend plugs. For best results, the end of the impedershould be 5/8� past the weld roll centerline. If desired,the impeders can be supplied with the end plugsdrilled and tapped to accommodate a wiper assemblyor centering device to support the impeder and prevent it from wearing out due to friction.

Inlet-OutletCoolant Lines Casing

Ferrite

Co-axial Coupling CoolantPassages

Fig. 17 Return flow impeder with coaxial coupling.

All above sizes are normally supplied as 9� longassemblies. Longer sizes are available. The couplingslisted above are intended to be soldered to two coppertubes for coolant inlet and outlet.

Return Flow Impeders CHART GTypical Return Flow Impeders

RFM-09-XXX 9 0.354 1/16� FPT 5/32�

RFM-10-XXX 10 0.394 1/16� FPT 5/32�

RFM-11-XXX 11 0.433 1/16� FPT 5/32�

RFM-12-XXX 12 0.472 1/16� FPT 5/32�

RFM-13-XXX 13 0.512 1/8� FPT 3/16�

RFM-14-XXX 14 0.551 1/8� FPT 3/16�

RFM-15-XXX 15 0.591 1/8� FPT 3/16�

RFM-16-XXX 16 0.630 1/4� FPT 1/4�

RFM-17-XXX 17.45 0.687 1/4� FPT 1/4�

RFM-19-XXX 19.05 0.750 1/4� FPT 1/4�

RFM-22-XXX 22.23 0.875 1/4� FPT 1/4�

RFM-24-XXX 23.80 0.937 3/8� FPT 5/16�

RFM-25-XXX 25.40 1.000 3/8� FPT 5/16�

RFM-27-XXX 26.97 1.062 3/8� FPT 5/16�

RFM-30-XXX 30.15 1.187 3/8� FPT 5/16�

RFM-33-XXX 33.32 1.312 1/2� FPT 3/8�

RFM-38-XXX 38.10 1.500 1/2� FPT 3/8�

RFM-44-XXX 44.45 1.750 1/2� FPT 3/8�

RFM-51-XXX 50.80 2.000 1� FPT 5/8�

RFM-57-XXX 57.15 2.250 1� FPT 5/8�

RFM-64-XXX 63.50 2.500 1� FPT 5/8�

RFM-70-XXX 69.85 2.750 1� FPT 5/8�

RFM-76-XXX 76.20 3.000 1� FPT 5/8�

RFM-89-XXX 88.90 3.500 1� FPT 5/8�

RFM-102-XXX 101.60 4.000 1� FPT 5/8�

RFM-114-XXX 114.30 4.500 1� FPT 5/8�

RFM-127-XXX 127.00 5.000 1� FPT 5/8�

RFM-140-XXX 139.70 5.500 1� FPT 5/8�

RFM-152-XXX 152.40 6.000 1� FPT 5/8�

PartNumber

Diameter(mm)

Diameter(in.)

ThreadSize

Inlet Tube

16

Integral Mandrel Impeders

Thermatool integral mandrel impeders (Figure 18)have an integral stainless steel bar to carry the torsional and tensile loads for an ID cutting or beadrolling head back to the attachment point on the mill.Heavy brass plugs at both ends are threaded toaccommodate the tow rod, and set screws are provided to prevent rotation. Tow rod material shouldbe nonmagnetic particularly in the area of the coil fluxto minimize induction heating.

The ends of the tow rod are threaded to suit thethreads on the impeder, and a flat should be milled orground at the top so that the set screw on the impedercan be tightened to prevent rotation. Mill coolant issupplied to the impeder through the hollow tow rod,and a short length of pipe is used to couple the scarfing head to the impeder (Figure 18). The coolantis discharged through holes drilled in the bottom ofthis section, so that coolant is kept away from theweld bead. By preventing the weld bead from beingcooled by impeder coolant, much more consistent IDscarfing can be achieved. The impeder should bepositioned so that the end of the brass bushing at thedownstream end is 1-1/2� beyond the centerline of theweld rolls. This will ensure that the ferrite is properlypositioned for best weld efficiency.

On small diameter tubes, integral mandrel impedersplace a much larger mass of ferrite in the weld zonethan conventional ID scarfing systems. Because ofthis, it is usually possible to weld at higher speeds, orto use less power at the same speed.

Threaded sizes shown are standard sizes and are normallyavailable from stock. Other threads are available.

Threaded Ends for Tow RodCasing Stainless Steel Bar

Coolant Passages Ferrite

Fig. 18 Integral mandrel impeder for use on small diameter tubes where space is not available for a solid mandrel.

CHART HTypical Integral Mandrel Impeder Sizes

ThreadPart

NumberDiameter

(mm)Rod Diameter

(in.)

IMI-050-XXX 0.50 0.19 3/8�-24

IMI-056-XXX 0.56 0.19 3/8�-24

IMI-063-XXX 0.63 0.25 3/8�-24

IMI-069-XXX 0.69 0.25 3/8�-24

IMI-075-XXX 0.75 0.25 1/2�-20

IMI-081-XXX 0.81 0.25 1/2�-20

IMI-088-XXX 0.88 0.31 5/8�-18

IMI-094-XXX 0.94 0.31 5/8�-18

IMI-100-XXX 1.00 0.31 5/8�-18

IMI-106-XXX 1.06 0.38 5/8�-18

IMI-113-XXX 1.13 0.38 5/8�-18

IMI-119-XXX 1.19 0.38 5/8�-18

IMI-125-XXX 1.25 0.38 5/8�-18

IMI-131-XXX 1.31 0.50 5/8�-18

IMI-150-XXX 1.50 0.50 3/4�-16

IMI-175-XXX 1.75 0.75 3/4�-16

IMI-200-XXX 2.00 0.75 1�-12

IMI-225-XXX 2.25 0.75 1�-12

IMI-250-XXX 2.50 0.75 1�-12

IMI-275-XXX 2.75 0.75 1�-12

IMI-300-XXX 3.00 0.75 1�-12

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Over Mandrel Impeders

Where more rigidity is required for internal scarfingand where adequate space is available, an over mandrel impeder (Figure 20) is recommended.

Rod diameters shown here are the maximum for eachsize impeder; however, smaller diameters can be provided to suit customer requirements. The impedersare provided with clearance holes for the specific mandrel rod diameters.

0.9375� 1/2�

1.0625� 1/2�

1.1875� 1/2�

1.3125� 1/2�

1.5000� 1/2�

1.75000� 3/4�

2.000� 3/4�

2.2500� 1�

2.5000� 1�

2.7500� 1�

3.0000� 1-1/2�

3.5000� 1-1/2�

OD Rod Diameter

Rigid Mandrel

CasingFerriteCoolant

Inlet

Coolant Outlet

1-1/2" minimum

Length to suit mill

Fig. 20 Over mandrel impeder for use where space permits a rigid mandrel.

Fig. 19 Integral mandrel installation.

CHART ITypical Over Mandrel Impeder Sizes

18

Flow Through Impeders

Coolant Inlets

Mandrel Manifold

Retaining Set Screw

Fig. 21 Impeder cluster assembly for large diameter pipe.

Impeder Cluster Assembly

With larger diameter pipe, it is advisable touse an impeder cluster. This is an assemblyof standard flow through impeders mountedto a manifold supported by the scarfingmandrel on a cantilevered bar. An impedercluster affords the ability to economicallyposition necessary ferrite in large tubeswithout resorting to expensive oversize single pieces of ferrite. Impeder clustersprovide improved ferrite cooling and easyand economical replacement of damagedferrite.

CHART JTypical Impeder Cluster Assembly Sizes

Cluster OD Minimum ID Number of Impeders

3.0� 1.0� 6

3.5� 1.5� 8

4.0� 2.0� 10

4.5� 2.5� 11

5.0� 3.0� 13

5.5� 3.5� 15

6.0� 4.0� 16

6.5� 4.5� 18

7.0� 5.0� 18

7.5� 5.5� 18

8.0� 6.0� 18

8.5� 6.0� 18

9.0� 6.0� 18

9.5� 6.0� 18

10.0� 6.0� 18

10.5� 6.0� 18

11.0� 6.0� 18

11.5� 6.0� 18

12.0� 6.0� 18

12.5� 6.0� 18

13.0� 6.0� 18

13.5� 6.0� 18

14.0� 6.0� 18

14.5� 6.0� 18

15.0� 6.0� 18

Thermatool Impeder Casings

Thermatool impeder casing is available in three different materials. Epoxy/glass casing conforms to theNEMA G-11 specifications and is a high temperatureformulation that has excellent mechanical strength.This is the least expensive grade. Silglass™ conformsto NEMA G-7 specifications and is a very high temperature silicone-based material that is ideal forreturn flow impeders and other types where long life isimportant. Because this material is fairly soft, it shouldbe supported so that it does not wear out due to friction with the strip. Ferroglass™ is a ferrite powder-filled epoxy/fiberglass that can increase weld speedsby as much as 50% when welding small diameter tubing. Its main application is in impeders smaller than 1� (25mm) in diameter. As diameter increases,the percentage of total ferrite contributed by theFerroglass casing becomes less, and the higher costis less easily justified.

Epoxy/Glass (NEMA Grade G-11): This type is the least expensive of the three, and is a good compromise between cost and performance. It is themost abrasion-resistant of the three, and is goodchoice when the impeder is not supported in the tube,and is therefore subject to mechanical wear from friction with the strip.

Ferroglass™: This is a ferrite powder-filledepoxy/fiberglass material, which greatly increasesspeed per kilowatt when welding small- to medium-diameter tubing. The inclusion of ferrite in the casingincreases the total mass of ferrite in the impeder andplaces it where it is most effective–close to the insidewall of the tube. The weld speed increase due to thisvaries with tube diameter and is most effective atsmall diameters, where it may contribute as much as50% more speed for the same weld power. As tubesize approaches 2� (51mm) OD, the speed increasedrops to a point where it does not justify the additionalcost of Ferroglass™ casing.

Silglass™: Silglass is our proprietary brand of siliconeresin bonded glass fibre. It was originally developedfor use on return flow impeders where its ability towithstand high temperatures for prolonged periods isessential. It is also an appropriate choice for largersizes of flow through impeders. It has less resistanceto abrasion than other types, so the impeder shouldbe supported in such a way that it does not dragagainst the strip. Silglass impeders are available in allsizes but are seldom used in flow through designsbelow 1� (25mm) OD.

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Note: For additional information about impeder casings,please contact the Thermatool spare parts group at 203-468-4100 or fax at 203-468-4285.

PartNumber

TDKNumber Size Description

FF 05-200 ZRS-5 05 x 200 Fluted Ferrite





















Thermatool Ferrite Grade 2006

Thermatool ferrite 2006 is the latest generation of specially formulated material selected exclusively foruse in all Thermatool impeders. It is a manganese-zincmaterial with a combination of high permeability, highsaturation flux density and an extremely low loss factor. Ferrite 2006 is recommended for high frequency welding applications and optimizes solid

state welding with Thermatool CFI2 technology. It isavailable in four configurations– flat sided, hollow, fluted and hollow fluted. It ensures achieving the highest welding speeds and long operating life. It iseasily recognized by its blue ends. Standard length is 200mm; however, other lengths can be supplied inmost cases as a special order.

20

CHART KThermatool Fluted Ferrite (FF)

Fluted Ferrite (FF)

How to Order Thermatool Ferrite

1. Identify the ferrite configuration required (Fluted, Flat Sided, Hollow, etc.).2. Define the OD and the length of the ferrite for Fluted (FF) and Flat Sided (FSF)

ferrite.3. Define the OD, ID and the length of the ferrite for Fluted Hollow ferrite (FHF) and

Hollow ferrite (HF).


PartNumber


FHF 10-03-200 ZRSH-10 x 3 10 x 03 x 200 Fluted Hollow Ferrite








































Fluted HollowFerrite (FHF)

CHART LThermatool Fluted Hollow Ferrite (FHF)


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PartNumber


PartNumber


FSF 03-200 ZR-3 03 x 200 Flat Sided Ferrite




















HF 06-03-200 ZRH-6 x 3 06 x 03 x 200 Hollow Ferrite

























22

CHART MThermatool Flat Sided Ferrite (FSF)

CHART NThermatool Hollow Ferrite (HF)

Flat SidedFerrite (FSF)

Hollow Ferrite(HF)


6000

5000

4000

3000

2000

1000

0 20 40 60 80 100 120 140 160 180 200

Temp. (°C)Saturations(Gauss)

Material (Ferrite)Saturation Flux Density (Gauss)Curie Temp. (°C)

A5500290

B5100240

D3200210

C4100190

A

B

C

D

Fig. 22 Saturation flux density vs. temperature for various grades of ferrite. Optimum performance requires proper cooling.

Thermatool Ferrite – General Information and Application

Characteristics of FerriteFigure 22 illustrates different characteristics betweentypes of ferrite and the significance of proper coolingfor optimum performance.

It also demonstrates that performance is not linear tothe curie point (temperature at which the ferrite losesits magnetic properties and becomes ineffective).Therefore care should be taken to provide maximumcooling, using a heat exchanger to stabilize temperature, if necessary.

The important characteristics in choosing a ferrite forinduction welding are:

• A high saturation flux density

• A high curie temperature

• Maximum stability through the operating temperaturerange

Ferrite rod and tube is available in many cross section shapes. Some of the most widely used arefluted designs with deep serrations. Fluted ferrite canhave double or more surface area than standard ferriterod, providing much improved cooling.

Placement of Ferrite MaterialPrecise placement of the ferrite material within thetube is a key factor in efficient performance. Ideally, ferrite should be up to and into the weld zone proper (Figure 3). The ferrite end should be 1/8� past thecenterline of the weld rolls. This position improves the impeder’s ability to focus the current on the weld zonewhere the energy is needed.

Because of the intense heat and spume, this is difficult. Various attempts have been made, using fluted and tubular shapes, to alleviate this problem.One of the more successful approaches is to attachthe ferrite to the fiberglass tube so that it extends outthe downstream end of the impeder, directly into theweld area. The effective tip is constantly kept awashwith coolant, keeping its temperature low and avoidingspume buildup.

In HF induction welding there must be enough of theright ferrite for the application. It must be placed in theproper position, with maximum cooling provided.

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Cutoff Blades

The Function of Blades and JawsThe heart of a flying cutoff system is in the dieset,where the cutting action occurs. The suitability of designand quality of manufacture of dieset components hasa major impact on the overall performance of the cutoff system; all the other advantages of the machineare compromised unless the blades and jaws in thedieset are of the finest quality and correctly installed.

Alpha’s continuing research with blade material, heattreatment and blade coating techniques has resultedin improved blades that are more long-lived and cost-effective. The industry’s first full-scale prototypeblade test facility dedicated to the study of blade performance has been established at Alpha’s development lab. A unique research machine hasbeen fabricated to test new development in this technology under simulated full-performance cuttingconditions.

Rapid Changes of Blades and JawsWith today’s mills operating at speeds in excess of800 feet per minute, the routine maintenance timerequired for changing blades and jaws must bereduced to an absolute minimum.

Standard on all Alpha cutoffs, a unique time-savingdesign provides the industry’s fastest, easiest andmost economical changeovers. Vertical and horizontalblades can each be changed in less than one minute.Changes are made right on the machine, on-line.

BladesThere are many types of blades on the market: vertical and horizontal, thicknesses from .060� to.500�, lengths from 2� to 20�, widths from 1� to 10�,coated and uncoated, in various grades of steel, pointconfigurations, bolt hole patterns and grindings.

Selecting the blades best suited for a particular application is very important for improving cut quality,extending mill uptime and increasing overall tubeproduct yields.

Vertical Blades

The vertical blade is the large blade that shears thetube in a downward motion, and is mounted in a(patented) quick change cartridge. A keyhole-shapedmounting hole and one screw is all that is required tomount the assembly into the dieset.

Rule of Thumb: Vertical Blade Thickness

Material Wall Thickness Multiplier

Low carbon steels 1.5 x WallStainless steel 1.75 x WallHigh carbon steel 2.0 x Wall

Standard Alpha Vertical Blade Thicknesses:

0.060� 0.090� 0.120� 0.150�

1.5mm 2.29mm 3.05mm 3.81mm

0.180� 0.250� 0.312�

4.60mm 6.35mm 7.92mm

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Cutoff Blades

Point StylesALPHASHEAR blades come in a variety of point configurations, each designed to yield a specific benefit.Each point style will perform differently depending onthe type of tubing to be cut. The variables are O.D.,wall thickness and material properties of the tube. Thecustomer will likely have to do some experimenting tofind the particular point configuration that produces thebest cut.

The following are the basic ALPHASHEAR blade pointconfigurations and their uses:

• Angle point–This is used when a customer is cuttingsquare tube presented to the cutoff on the corner, orcutting small or medium light wall round tube.(Examples are shown in Figures 1A, 1B and 1C).

The horizontal blade is the small blade that scarfs thetop of the tube, perpendicular to the vertical blade. Thematerial removed by the horizontal blade (or alsoknown as a scarfing blade) allows the vertical blade toproduce a dimple-free cut.

Rule of Thumb: Horizontal blade thickness is .006�(0.15mm) greater than the vertical blade thickness.

Standard Alpha Horizontal Blade Thicknesses:

0.066� 0.096� 0.126� 0.156�

1.67mm 2.43mm 3.19mm 3.95mm

0.186� 0.256� 0.318�

4.71mm 6.48mm 8.05mm

Blade Ordering InformationALPHASHEAR blades are priced based on orders of 25 pieces or more; quantity and blanket orderingdiscounts are available. When ordering, exact requirements must be established by dieset number,machine model number and machine serial number.In-stock blades will be shipped within 24 hours. Out-of-stock blades may take 5 or 6 weeks to manufacture.

• Radius point–One of themost common of the bladestyles used in cutoffs, thiswill cut almost any size orthickness of round tube.Special radius points cansometimes be used onsquare tube cut on the corner. (An example isshown in Figure 2).

Figure 1A Figure 1B Figure 1C

Figure 2

Horizontal Blades

Figure 3A Figure 3B Figure 3C

• Angle and radius point–Also known as double radius,it is usually used on larger diameter tubing where theside edges of the tube will be cut by the angle of theblade, and the top and bottom cut by the blade radius.(Examples are shown in Figures 3A, 3B and 3C).

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Cutoff Jaws

Jaws are the precisely dimensioned parts of highspeed tool steel that clamp the tube in the dieset whileit is being cut. In addition, jaws provide half the cuttingsurface. They also set the proper amount of clearancebetween the jaws and vertical blade to produce theoptimum cut quality, or shearing action.

The amount of clearance between the jaws can dramatically affect cut quality. Optimum clearancedepends on variables such as wall thickness, lubrication,material ductility and blade velocity. As a rule of thumb,blade clearance of 10 percent of the wall thickness oneach side of the vertical blade will result in a good,dimple-free cut with minimum burr. Achieving an optimumcut, however, may require some experimentation.

Adjusting the blade clearance is a simple task usingthe jaw setup fixture supplied with all Alpha double-cutmachines. Inspection and adjustments take placewhen the jaws are mounted in the fixture, which duplicates the actual setup in the dieset.

The Making of JawsSimilar to ALPHASHEAR blades, all Alpha jaws aremade from high speed tool steel which lasts far longerand produces a higher quality cut than mild steel. Mostjaws are designed to allow tube diameter tolerance of +/– .004�; the figure can vary depending on thematerial and shape of the tubing, and whether a singleor double cut is employed.

The steps involved in fabricating a set of jaws are asfollows:

1. Jaw blanks are cut from the tool steel, allowingample material for all subsequent machining andprocessing steps.

2. The blanks are ground on a Blanchard type grinderto true up all surfaces for precision machining.Typical tolerances on a set of jaws range from.0005� to .002�.

3. After inspection, the ground blanks are placed onNC-controlled machinery for rough machining.

4. The roughed-out jaws are then heat treated forhardening and durability using an atmospheric-controlled process.

5. The hardened jaws are then prepared for finishgrinding–the most critical step in their manufacture.Dimensions and tolerances must be held or malfunctions during operation can be expected.

Jaw Ordering InformationWhen ordering jaws from Thermatool/Alpha, or inquiring about prices and lead time, please includethe following information:

1. Machine model and serial number.

2. Dieset type and model number.

3. Size of tube being produced (wall thickness and outside diameter).

4. Corner radius of tube, if tube is other than round.

5. If non-round, how tube is presented to the cutoffmachine, i.e. on the diamond, flat, inclined somenumber of degrees, etc.

For your convenience, an Ordering Form can befound on page 28. Simply fill out, photocopy andfax to us at 203-468-4285.

6. After finish grinding and inspection, the jaws areprepared for shipment: etched with part numbers,demagnetized, oiled to prevent rust and protectivelywrapped.

From the time an order is placed to the time the jawsare shipped to the customer is usually 6 to 8 weeks. Insome emergency situations they can be produced inas little as 3 days.

Cutoff Jaws Ordering Information

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Customer Name

Purchase Order No.

Date

Material

Tube tolerance

Wall thickness

Rounds

Mother tube forming: (please check) � bottom line � center line

Dieset

Tube OD

Other information

Squares and Rectangles

Mother tube forming: (please check) � bottom line � center line

Material

Wall thickness

Tube tolerance

Mother tube OD

Corner radius

Machine configurationUpright or angular?

Dimensional Information

Please indicate the mill direction

A-Angle

B-Diameter

C-Width

D-Width

E-Tolerance

F-Corner radius

Thermatool Welding, Heating, Cutting and Bundling Systems

31 Commerce StreetP.O. Box 120769

East Haven, CT 06512-0769USA

Tel: 203-468-4100Fax: 203-468-4281

Website: www.thermatool.com

Thermatool Corp. Certified ISO 9001 10/99

Thermatool-Application-Select.pdf

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