ASME SECTION VIII, DIV.1 flanged pipewell calculation question
ASME SECTION VIII, DIV.1 flanged pipewell calculation question
(OP)
I am running an ASME SECTION VIII, DIV.1 calculation for a flanged pipewell (partial drawing attached). The flange is 3" 1500# F22, and the pipe is 2" 160S 347SS (customer required combination). The flange will be machined for a full penetration weld and welded from both ends. You can see from the drawing that the material removed from the flange There will be an ER309 butter layer laid on the flange, followed by PWHT of flange, and then the final attachment to the pipe with the appropriate SS filler.
The flange shown is a hubbed flange, but the welding time required will be substantial, so I'm looking at what thickness would be required for a non-hubbed blind flange. With a full penetration attachment as shown, my understanding is that the effective ID of the flange is then the ID of the pipe. If that is the case, then the diameter of the central opening is less than the short span of the flange, and I could use UG-39(b)(1) to determine reinforcement requirements. However, if the pipe ID is not the effective ID, then I have to go with UG-39(c), and ultimately Appendix 14. However, the welds referenced there in UW-13 and UG-34 aren't very representative of the type of weld we're performing in my estimation.
Is the effective ID of the flange given a weld of this nature covered in the BPVC code?
The flange shown is a hubbed flange, but the welding time required will be substantial, so I'm looking at what thickness would be required for a non-hubbed blind flange. With a full penetration attachment as shown, my understanding is that the effective ID of the flange is then the ID of the pipe. If that is the case, then the diameter of the central opening is less than the short span of the flange, and I could use UG-39(b)(1) to determine reinforcement requirements. However, if the pipe ID is not the effective ID, then I have to go with UG-39(c), and ultimately Appendix 14. However, the welds referenced there in UW-13 and UG-34 aren't very representative of the type of weld we're performing in my estimation.
Is the effective ID of the flange given a weld of this nature covered in the BPVC code?





RE: ASME SECTION VIII, DIV.1 flanged pipewell calculation question
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: ASME SECTION VIII, DIV.1 flanged pipewell calculation question
RE: ASME SECTION VIII, DIV.1 flanged pipewell calculation question
My assumption is you are designing a flange to a B16.5 pattern. I further assume you are trying to minimize the thickness. And further that you are casting about for a flange I.D. on which to perform calculations.
My suggestion was to run this as a loose flange under Appendix 2, with ID equal the pipe OD and see if the thickness is acceptable. This is sometimes a simpler method than treating as a flat head and having to consider reinforcement.
This whole thing, IMO, I going to hang on your weld metal being of at least equal strength to the F22 material.
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: ASME SECTION VIII, DIV.1 flanged pipewell calculation question
RE: ASME SECTION VIII, DIV.1 flanged pipewell calculation question
Full-pen welds are a feature that my company hangs their hat on as resulting in a superior product. No need debating that can of worms, because they are not going to change their mind on that topic.
RE: ASME SECTION VIII, DIV.1 flanged pipewell calculation question
If it all seems too hard then change to a partial pen weld both sides and get a superior product to the proposed welding detail.
RE: ASME SECTION VIII, DIV.1 flanged pipewell calculation question
Acceptable to the AI.
'cant use a modified flange as ANSI Std.
Even if camouflage the calculations.
General Blr. CA,USA
RE: ASME SECTION VIII, DIV.1 flanged pipewell calculation question
I would be interested to see what the OP ended up going with.