Spot Welding Supplies - Electrodes, Holders, and Accessories - Tuffaloy Products

TUFFALOY WELDING DATA


RECOMMENDED USES OF RESISTANCE WELDING MATERIALS



GROUP A COPPER-BASE ALLOYS
RWMA Class 1 alloy TUFFALOY 88
CADMIUM-COPPER, suited to welding aluminum and magnesium alloys, coated materials, brass and bronze.

Class 1 alloy is superior to pure copper as an electrode material and is recommended as a general purpose material for resistance welding use. It may be used for spot welding electrodes, seam welding wheels and welding fixture components. It is not heat treatable.

RWMA Class 2 alloy TUFFALOY 77
CHROMIUM-COPPER, suited to welding cold-and hot-rolled steels, stainless steel, and low-conductivity brasses and bronzes.

Class 2 alloy is a superior resistance welding electrode material, recommended for high-production operations. It's used for welding electrodes, projection welding dies, seam welding shafts and bearings, flash and butt welding dies, and current-carrying structural components. Available in forms for use as welding gun arms, welding platens and secondary-circuit structural members. It is heat treatable.

TUFFALOY Z
ZIRCONIUM-CHROMIUM-COPPER is suited to welding galvanized steel and other metallic-coated steel.

This is a specially heat-treated alloy which meets the minimum electrical conductivity and hardness specifications of Class 2 alloy.

RWMA Class 3 alloy TUFFALOY 55 and 55A
NICKEL-COPPER (55) and BERYLLIUM-NICKEL-COPPER (55A) are suited to welding steels having high electrical resistance, such as stainless steel.

Class 3 alloy is recommended for projection welding dies, and flash and butt welding dies. With its higher strength it is also used on highly-stressed current-carrying parts such as electrode shanks and heavy-duty electrode holders. It is heat treatable.

RWMA Class 4 alloy TUFFALOY 44
BERYLLIUM-COPPER has extremely high hardness, and is recommended for projection, flash and butt welding dies. It has lower conductivity than Class 3 alloy but it is harder and more wear resistant. It should be considered where there is concern with high pressure density and severe wear, but where heating, due to its low conductivity, is not excessive.

It is used frequently in the form of inserts, die facings. and seam welder bushings. It is available in the annealed condition which is more readily machined and then subsequently heat treated.


GROUP B REFRACTORY METAL COMPOSITIONS


RWMA Class 10 TUFFALOY 1W
TUNGSTEN 55%-COPPER 45%, suited for facings and inserts for projection welding electrodes and flash and butt welding dies. It is recommended where (relatively) high electrical conductivity and some degree of malleability is desired.

RWMA Class 11 TUFFALOY 10W
TUNGSTEN 75%-COPPER 25%, suited to similar applications as Class 10, and for facing on electrode forming dies. It is harder than Class 10, and is for general use in projection welding electrodes.

RWMA Class 12 TUFFALOY 20W
TUNGSTEN 80%-COPPER 20%, suited for electro-forming and electro-forging die facings, and for electrode facings used to upset studs and rivets. A material for heavy-duty projection welding electrodes and dies.


RWMA Class 13 TUFFALOY 100W
TUNGSTEN

RWMA Class 14 TUFFALOY 100M
MOLYBDENUM
Class 13 & 14 materials are used primarily for welding or electro-brazing non-ferrous metals having relatively high electrical conductivity. They are suited to cross-wire welding of copper and brass, and for welding copper wire braid to brass or bronze terminals. Special set-ups and procedures are required,

R.W.M.A. RECOMMENDED ELECTRODE MATERIALS  FOR SPOT WELDING

Using Conventional Spot Welding Methods

 

LEGEND
Block Interpretation

 WELDABILITY
ELECTRODES AGAINST 
ELECTRODES AGAINST 
SPECIAL INFORMATION 

WELDABILITY

A- Excellent    

B- Good

ELECTRODES, R.W.M.A. Specifications

I- Group A, Class 1-Tuffaloy 88

II- Group A, Class 2 -Tuffaloy 77 & Tuffaloy Z

III- Group A, Class 3 -Tuffaloy 55

Materials indicated in squares are second choice, example                             

 II

SPECIAL INFORMATION

1- Special conditions required

2 - Good practice recommends cleaning before welding

3 - If plating is heavy, we strength is questionable.

 

Data based on Resistance Welding Equipment Standards, Bulletin 16, a publication of the Resistance Welder Manufacturers Association.

TO WELD SIMILAR METALS

FERROUS
Tin Plate Steel
Terne Plate Steel
Galvanized Iron
Zinc Plate
Cadmium Plate Steel
Chrome Plate Steel
Stainless Steel 18-8 Type
Scaly H.R. Steel
C.R. Steel H.R. Steel (clean)
READ BLOCK UNDER METAL TO BE WELDED
 B I  A I A I
 II
B  I A II A III
 II
B  I

  II

 A  II 
I  3 I 3 I
 II
3  I 3 II 3 III
 II
  I

  II 

 2  II   

 

 NON-FERROUS
 
Aluminum Alloys Duraluminum
Cupro Nickel
Nickel Silver
Nickel
Nickel Alloy Monel Nichome (High Res)
Brass Yellow 25-40% Zinc
Phosphor Bronze Grade A, C & D
Silicon Bronze Everdur Olympic Duronze Herculoy
 
 B I
 II
B I
 II
A II B  II A II A II B  II AB II  AB  II 
I
 II
2 I
 II
2 II   II   II   II   II   II    II   

TO WELD DISSIMILAR METALS

FERROUS ALLOYS
Stainless Steel 18-8 Type 
Chrome Plate Steel
Cadmium Plate  Steel 
Galvanized Iron Zinc Plate    
 Terne Plate   Steel 
    Tin Plate        Steel
  Cold Rolled Steel Hot Rolled Steel, Clean
 A II
 III
A II B II B  I A I
 II
B I
III   II 3 II 3 II 3 II 3 II 3
Tin Plate Steel 
B  II
 III
B  II  B  I
 II
B  I  B  I
 II
 
I    I  3  I  3  I  3  I  3 
 Terne Plate Steel  
B II B II B I
 II
B I  
I  3 I 3 I 3 I 3
Galvanized Iron   Zinc Plate 
B  II  B  II  B  I   
I  3  I 3 I  3 
Cadmium Plate  Steel 
B  II  B  II   
I  3  I  3
Chrome Plate Steel 
A  III
 II
 
II  3 
NON-FERROUS ALLOYS
Nickel Alloys
Nickel
Phosphor Broze
Silicon Bronze
 Yellow Brass
Nickel Silver
Cupro Nickel
 B II B II B II B  II B II B II
II    II   II   II   II   II  
Silicon Bronze Everdur – Olympic Bronze – Herculoy
B  II B  II  B  II A  II  B  II  
II    II    II    II    II   
 Nickel Silver 
B II B II B II B II  
II  1 II   II 1 II  
Nickel Alloys
A II  B  II 
 
ALUMINUM
ALUMINUM ALLOYS DURALUMINUM
B  I
 II
 
I
 II
2 
II    II  
Stainless Steel  8-8 Type
B  II  B  II 
III
 II
1 II
 III
3


MINIMUM PHYSICAL PROPERTIES FOR R.W.M.A. ALLOYS

Published Standards of the Resistance Welder Manufacturers Association

GROUP A Copper Base Alloys
  
 CLASS
TUFFALOY   NUMBER 
 PROPORTIONAL LIMIT TENSION P.S.I.
HARDNESS ROCKWELL 
CONDUCTIVITY PER CENT I.A.C.S. 
 ULTIMATE TENSILE STRENGTH P.S.I.
 ELONGATION % IN 2" OR 4"DIAMETER
  ROUND RODS

Up to 1" diameter

1

2

3

 88

77

55 

 17,500

35,000

50,000 

 65-B

75-B

90-B 

 80

75

45 

 60,000

65,000

100,000 

 13

13

9 
  1" to 2" diameter
1

2

3

 88

77

55

 15,000

30,000

50,000 

 55-B

65-B

90-B 

 80

75

45 

 50,000

55,000

95,000 

 14

13

9
  2" to 3" diameter
1

2

3

 88

77

55

 15,000

25,000

50,000

 55-B

70-B

90-B

 80

75

45 

 50,000

55,000

95,000

 15

13

9 
BARS Square Rectangular Hexagon Up to 1" thick
1

2

3

 88

77

55

 20,000

35,000

50,000

 55-B

70-B

90-B

 80

75

45 

 60,000

65,000

100,000 

 13

13

9
  Over 1" thick
1

2

3

 88

77

55

 15,000

25,000

50,000

 50-B

65-B

90-B 

 80

75

45 

 50,000

55,000

100,000 

 14

13

9
FORGINGS Up to 1"
1

2

3

 88

77

55

 20,000

22,000

50,000 

 55-B

65-B

90-B

 80

75

45 

 45,000

55,000

94,000

 12

13

9
1" to 2"
1

2

3

 88

77

55

 15,000

21,000

50,000 

 50-B

65-B

90-B  

 80

75

45 

 40,000

55,000

94,000 

 13

13

9 
  Over 2"
1

2

3

 88

77

55

 15,000

20,000

50,000  

 50-B

65-B

90-B   

 80

75

45 

 40,000

55,000

94,000  

 –

12

5 
  All sizes
 4 44 85,000 33-C  20  140,000  .5
CASTINGS  All sizes
2

3

4

5 

 77

55

44

66 

 20,000

45,000

60,000 

12 to 16,000

 55-B

90-B

33-C

65 to 85-B 

 70

45

18

10 to 15 

 45,000 

85,000

90,000

65 to 75,000

 12

5

.5

2 to 10
 GROUP B Refractory Metal Compositions
 Rods, Bars & Inserts  10

11

12

13

14

 1W

10W

20W

100W

100M 

   72-B

94-B

98-B

69-A

85-B 

 35

28

27

30

30 
135,000

160,000

170,000

200,000

200,000

 Ultimate Compression Strength P.S.I.

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Spotwelding Consultants Inc.

4209 Industrial
Rowlett, Texas 75088
Toll Free: 888-255-6780
Phone: 972-475-0874
Fax: 972-475-5024