®COPYRIGHT
2000 THE ESAB GROUP, INC. LESSON
VI 6.7 AWS
SPECIFICATION A5.28-96 6.7.0.1
This specification is entitled Specification
for Low
Alloy Steel
Filler Metal
for Gas
Shielded
Arc Welding.
It covers the solid bare wires for welding those steels commonly re-
ferred to as the chromium-molybdenum
(chrome-molys), manganese-molybdenum (manganese-molys),
nickel alloy and other low alloy steels. The wires referred to in this lesson
are for use with the gas-metal arc
welding process and also may be used as filler metals for
the GTAW process.
6.7.0.2 The
letter-number designations have the same significance as those used in the
carbon steel specification shown in
Figure 4. Using ER80S-B2 as an example, the letters ER
indicate that it is an electrode or
a welding rod; will produce weld metal of 80,000 psi tensile
strength (80); is a solid bare wire
(S) of a specific chemical composition (B2) as described in
Figure 8. Major
Alloying Elements - % By Weight AWS
Class Carbon
Chromium Molybdenum
ER80S-B2L *0.05
1.20 - 1.50 0.40
- 0.65 ER80S-B2
0.07 - 0.12 1.20
- 1.50 0.40 -
0.65 ER80S-B3L
0.05 2.30
- 2.70 0.90 -
1.20 ER80S-B3
0.07 - 0.12 2.30
- 2.70 0.90 -
1.20 * Single
figure denotes maximum CHEMICAL
COMPOSITION CHROMIUM-MOLYBDENUM SOLID BARE WIRES FIGURE
8 6.7.1
The
Chromium-Molybdenum
Types (Cr-Mo)
- The letter “B” designates a Cr-Mo
wire to be used for welding the Cr-Mo
pressure vessel steels, and the number that follows desig-
nates the chemical composition of the
filler metal. If the last number is followed by an “L”, it
indicates that the wire has a low carbon
content. 6.7.1.1
Figure 8 shows only the major chemical
composition requirements for these filler metals.
For complete requirements, see AWS A5.28-96 Filler Metal Specification.
6.7.1.2 Figure
9 shows the mechanical property requirements for the Cr-Mo weld metal.
6.7.1.3 Filler
metals of the preceding classifications are used to weld the 1/2 Cr-1/2 Mo, 1
Cr-1/2 Mo, 1-1/4 Cr-1/2 Mo, and 2-1/4
Cr-1 Mo steels that are used in welding high tempera- ture
piping and pressure vessels. They provide a degree of corrosion resistance
and are used for
welding dissimilar grades of Cr-Mo steels and carbon steels.
