Page 194 - Handbook of Structural Steel Connection Design and Details

Welded Joint Design and Production

Welded Joint Design and Production 179

nickel-copper-manganese-molybdenum-columbium alloy steel
plates for general applications. Three different grades and three
different conditions provide minimum yield strengths from 50 to 90
ksi. When this steel is to be welded, a welding procedure should be
developed for the specific grade of steel and intended service.
According to D1.1-98, no preheat is required with SMAW, SAW,
GAW, and FCAW electrodes that are capable of depositing weld
metal with a maximum diffusible hydrogen content of 8 mL/100 g.
ASTM A852: Covers quenched and tempered high-strength–low-
alloy structural steel plates for welded, riveted, or bolted construc-
tion. It is intended primarily for use in welded bridges and build-
ings where savings in weight, added durability, and good notch
toughness are important. This steel specification has substantially
better atmospheric corrosion resistance than that of carbon struc-
tural steels. It has similar chemistry requirements to A588, but has
been quenched and tempered to achieve the higher-strength level.
Welding technique is important, and a welding procedure suitable
for the steel and intended service should be developed. The specifi-
cation limits the material thickness up to and including 4 in.
According to D1.5-96, A852 is an approved bare metal under the
A709 specification and D1.1-98 requires welding procedure qualifi-
cation for this steel.
ASTM 913: Covers high-strength–low-alloy structural steel
shapes in grades 60, 65, and 70 produced by the quenching and
self-tempering process. The shapes are intended for riveted, bolted,
or welded construction of bridges, buildings, and other structures.
Although not in D1.5, the maximum yield strengths are 60, 65, and
70 ksi for the respective grades, while the minimum tensile
strengths are 75, 80, and 90 ksi. A913 can be welded with a low-
hydrogen process, and according to D1.1-98, it must provide a maxi-
mum diffusible hydrogen content of 8 mL/100 g. The shapes should
not be formed or postweld heat-treated at temperatures exceeding
1100°F (600°C).

3.1.3 Older and miscellaneous base metals
Cast iron. Cast iron was a popular building material through the
late 1800s, and occasionally an engineer is faced with the need to
make additions to a cast-iron column, for example. Cast iron may also
be encountered in miscellaneous structural applications such as
ornate light poles, archways, and other components with decorative
functions in addition to accomplishing structural support. Cast iron
can be successfully welded but with great difficulty. Unless the weld-
ing involves repair of casting defects (voids, slag, or sand pockets), or

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