Production Impact Tests ASME VIII, Div.1

[wsmith22]

How does industry handle production impact tests on carbon steel vessels?

Besides needing impact tested material and WPS & PQR, how is the production piece handled?

i.e. how do you test production welds? Do you need to re-test the material? HAZ of base metal?

Any input would be greatly appreciated.

 

[metengr]

Well, for production work the best approach is to either have a prolongation or coupon of the same heat of steel used in fabricating the pressure vessel or find a piece of test plate that is similar in wall thickness and chemical composition to the material used in production. Check to make sure that the carbon equivalent and mechanical properties of the test plate are equivalent to the material specified in production.

Fabricate a weld coupon using the weld procedure and heat treatment specified in production and submit for CVN impact testing, following the CVN impact test requirements of the original code of construction for the vessel. I recommend you review ASME Boiler and Pressure Vessel Code, Section VIII, Div 1, Part UCS-67.

 

[wsmith22]

Thanks Metengr.

additonal question: do you need to make a test coupon for each heat number and different item? Vessel may be SA-106 Gr.B, SA-105, SA-516 Gr.70. Do you need a test coupon for say 8" pipe to ANSI flange, 3" pipe to 8" pipe, 8" pipe cap to 8" pipe, etc.?

 

[metengr]

Unfortunately, the answer is it depends on design/service conditions. Your piping design would probably fall under B31 Pressure piping, while the pressure vessel itself under ASME Section VIII.

Both of these codes of construction provide specific details on low temperature service and impact testing requirements.

 

[weldtek]

WSMITH22
If you are working to ASME Sec VIII, you must perform a production test on material from one of the heats used in production. Only category A and B welds must be represented, so, only welding processes used for those applications must be tested.
Th rules are detailed in UG 84.

 

[wsmith22]

Thanks metengr & weldtek. I reviewed UG-84(i) and spoke with our inspection agency and there said the same thing.

The problem is an A.I. once gave me some incorrect info.