Re: Hydrotest (High point) Vents

My last take on this issue. From ASME B31.3.

300.2. Seal weld. A weld intended primarily to provide joint tighteness againts leakage.

311.2.6. Seal welds ... shall NOT be considered as contributing ANY strenght to the joints.

And of course the B31 allow seal welding. It has been mentioned in 300.2, 311.2.6, 314.1, 328.5.3, 331.1.3 and many more.

The AWS Journal has run a good article on how a strenght joint are made and when do you consider it. Check it out.

• In PipingDesign@yahoogroups.com, sviswan@... wrote:
  >
  > Seal welding is different from a full penetration strength weld.
  The seal
  > weld does not affect HAZ as much as the strength. I think ASME
  B31.3 allows
  > seal welds on threaded joints.
  >
  > In one of the standards, perhaps Bechtel. A threadolet and plug is
  used as
  > the vent and drain. A seal weld is done after the hydro test.
  >
  > Sajit
  >
  > Maybe the piping codes are different, but Section VIII doesn't
  permit
  > welding after the hydrotest.
  >
  >
  >
  >
  > Save a tree...please don't print this e-mail unless you really
  need to.
  >