American Welding Society Forum
I have a CWI test questions that I am having trouble understanding. It goes as follows.
What are the minimum preheat and interpass temperatures for welding 1/2 inch thick ASTM A709 Grade 36 Steel with an E6013 electrode when the base metal temperature is less than 32 F.?
a) 0 preheat 32 interpass
b) 32 preheat, 32 interpass
c) 50 preheat, 50 interpass
d) 70 preheat, 32 interpass
e) 70 preheat, 70 interpass
(All temps in F)
My solution: D per page 57 D1.1 pg 57. Note a requires 70 for preheat, but maintaining interpass temp.
Key Solution: E
This is confusing. Does the interpass temperature now change to 70 due to the below 32 temp before the preheat? I was under the impression that the interpass temps would be okay above 32 after the original preheat to 70.
I probably would have made the same choice as you.
Maybe it's referring to Table 3.3 Note 2 --> 5.6 --> "Minimum interpass temperature requirements shall be considered equal to the preheat requirements, unless otherwise indicated on the WPS."
If so, that's tough.
In my humble opinion, the answer is e), which would support my thinking that the minimum interpass temperature should be at least as high as the minimum preheat temperature.
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