ASME IX QW407.4
ASME IX QW407.4
(OP)
Dear all,
I have a question regarding ASME IX (2010) QW 407.4.
"QW-407.4 For ferrous base metals other than P-No. 7,
P-No. 8, and P-No. 45, when a procedure qualification test
coupon receives a postweId heat treatment exceeding the
upper transformation temperature or a solution heat treatment
for P-No. lOH materials, the maximum qualified base
metal thickness, T, shall not exceed 1.1 times the thickness
of the test coupon."
So for my understanding. When I weld a Duplex/Superduplex (P10H) test coupon and give him a solution annealing, which is required by the product standard my qualified thicknes is limited to 1.1xt?!
If I don't do a soloution heat treatment the thicknes is 2xt?
Can anybody tell me if my understanding is correct and if it's like this the technical reason for it?
Solution heat treatment is only to eliminate sigma phases and doesen't touch the basic structure or change the ferrite/austenite ratio.
Thanks in advance!
I have a question regarding ASME IX (2010) QW 407.4.
"QW-407.4 For ferrous base metals other than P-No. 7,
P-No. 8, and P-No. 45, when a procedure qualification test
coupon receives a postweId heat treatment exceeding the
upper transformation temperature or a solution heat treatment
for P-No. lOH materials, the maximum qualified base
metal thickness, T, shall not exceed 1.1 times the thickness
of the test coupon."
So for my understanding. When I weld a Duplex/Superduplex (P10H) test coupon and give him a solution annealing, which is required by the product standard my qualified thicknes is limited to 1.1xt?!
If I don't do a soloution heat treatment the thicknes is 2xt?
Can anybody tell me if my understanding is correct and if it's like this the technical reason for it?
Solution heat treatment is only to eliminate sigma phases and doesen't touch the basic structure or change the ferrite/austenite ratio.
Thanks in advance!





RE: ASME IX QW407.4
Why? Because if you exceed the upper transformation temperature or the original solution treatment temperature you are altering the bulk mechanical and corrosion properties of what was originally supplied by the material specification, especially the balance of phase constituents required for duplex stainless steel alloys.
Look at rules required for subcritical post weld heat treatment in ASME B&PV Code. For a subcritical post weld thermal treatment you are not affecting bulk mechanical properties.
RE: ASME IX QW407.4
tzhanks for your quick response.
Your view seems logical but where can I find a proof for this interpretastion. The ASME is not very clear.
RE: ASME IX QW407.4
You may find that this statement is not quite correct.
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: ASME IX QW407.4
Nevertheless is there a Para or clarification which helbs me to proof this interpretation?
RE: ASME IX QW407.4