I checked the footnote of Table 3.2, it is
When the base metal temperature is below 32°F [O°C], the base metal shall be preheated to a minimum of 70°F [20°C] and the minimum interpass
temperature shall be maintained during welding.
Did not mention about thickness.
Second, How to know difference of Group I and Group II metal/filler comnination in Table 3.1. I can see no difference.
Thanks in advance
By Duke
Date 11-06-2010 04:31
Edited 11-06-2010 04:35
yyq4797 is referring to Table 3 and 4 in the ASTM A572; here's note B from table :
"Columbium shall be restricted to the following thicknesses and sizes unless
killed steel is furnished. Killed steel shall be confirmed by a statement of killed steel
on the test report, or by a report on the presence of a sufficient quantity of a strong
deoxidizing element, such as silicon at 0.10 % or higher, or aluminum at 0.015 %
or higher..."
And T3 thickness limits are as yyq4797 states.
Table 3 is Alloy Content.
Take a look at Table 1; Maximum Product thickness or Size... You can get 6" thick plates in Grade 42, 4" in Gr. 50.
Limited by use of non killed steels in Tables 2 and 3