Is a welded tubesheet joint a category B or C?
Is a welded tubesheet joint a category B or C?
(OP)
Is a welded tubesheet joint considered a Category B or Category C joint? And if an efficiency of 1.0 is wanted, does it have to be RT'd (or UT'd)? Here is a pic of what i am talking about . . . .
Also, if i specify a Joint Efficiency of .85, is it governed by the lowest joint effiency of the entire vessel? For example, I have a heat exchanger with welded tubesheets and welded channels with mutiple nozzles. The nozzles have a Category D, Type 3 Joint with no RT, does that make the vessel a Joint Efficiency of .60?
Also, if i specify a Joint Efficiency of .85, is it governed by the lowest joint effiency of the entire vessel? For example, I have a heat exchanger with welded tubesheets and welded channels with mutiple nozzles. The nozzles have a Category D, Type 3 Joint with no RT, does that make the vessel a Joint Efficiency of .60?





RE: Is a welded tubesheet joint a category B or C?
Second, joint efficiency is applied only to butt-joints. Corner joints are assigned E = 1 when needed. See Table UW-12 Type (7).
Third, joint efficiency is used for design of a single component only. E for any component does not depend on the E of any other. See UW-12, second sentence.
Your nozzles likely are corner joints, no E needed.
Recommend further reading, including Appendix L.
Regards,
Mike
RE: Is a welded tubesheet joint a category B or C?
RE: Is a welded tubesheet joint a category B or C?
Your joint shown is Catagory C. One can make tubesheet to shell welds as catagory B as well.
RE: Is a welded tubesheet joint a category B or C?
RE: Is a welded tubesheet joint a category B or C?
RE: Is a welded tubesheet joint a category B or C?
RE: Is a welded tubesheet joint a category B or C?
Regards,
Mike
RE: Is a welded tubesheet joint a category B or C?
If you require RT then go to a Butt Weld configuration with a hub machined into your tubesheet, but there are additional criteria such as App 20 if you have a plate or additional tensile testing to UW-13(f) for forgings.
RE: Is a welded tubesheet joint a category B or C?
I am not sure what component it is.
As has been stated, T-to-TS welds are a class of their own. Seal weld only, seal with filler, strength welds, again with and without filler, flush, recessed, back face........There are many variations and each has its own needs.
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Plymouth Tube
RE: Is a welded tubesheet joint a category B or C?
RE: Is a welded tubesheet joint a category B or C?
RE: Is a welded tubesheet joint a category B or C?
Your nozzles and cylinder-tubesheet joints appear to be corner joints, no RT needed, E = 1 if needed.
If cylinders are butt-welded, both Cat A and Cat B joints, E will be assigned based on RT selected. E will only be used for design of the cylinders, and perhaps some other calculations such as in Part UHX, but will affect only the cylinders. Cat A joints likely will govern.
Your vessel has no "overall" joint efficiency.
Regards,
Mike