We are making a pressure vessel under code ASME VIII Dv 1, in the WPS is address to a welding preheat at 200 Farenheit deegres, the (Tw) thicnees are 2 Inches. the welding temp interpaas are 450 F. But when the welders are going to make the Gouging, the preheat torches are shutdown and the temp for the gouging go down to 120 F I am wondering if this a good practices. there are some Paragraf in the code the mention some thing about it.

the area that was gouging just have V.I after grainig and clean.

this vessel have a PWHT.

thanks

fredy

How is back gouging done? If using an "arc air" or oxy-propane torch preheat temperature should be maintained. Altough I don't see any specific Code requirement, use of these equipment is pretty similar to welding. Gouging by grinding or chisel does not raise problem, unless because of the material, the pre-heat is to be maintained.
Mauro