vent hole in the reinforcement pads

dreamschool-

I've never heard of a post construction test of a repad. I have seen leaks resulting in weep hole weepage (?) in piping connection and tank nozzle repads, not on vessels. I have even seen well meaning technicians install a valve into the leaking threaded connection and then close the valve... I've never seen any effort to be sure that the weep hole is visible. If the vessel is insulated, the entire repad will be under insulation.

I think you'll find thread794-25516 interesting reading.

jt

I agree with jte. The weep hole in a repad serves two purposes; to allow for entrapped gas to escape during welding of the repad to the vessel wall and to detect any leakage of vessel contents during service. Having insulation cover a weep hole is not a problem because should a leak develop between the repad weld and the shell/nozzle attachment weld, you will know.

Do not place any fittings on the weep hole or plug weld the weep hole!!

Weep holes exposed to outside weather conditions are often plugged with caulking. It keeps the water our, but will not stop a product leak from the inside.

Steve Braune
Tank Industry Consultants

See SecVIII Div1 UW-15(d). Do not forget the requirements of
UG-96(b) and UG-99(g)(3).

called telltale hole, advises if the vessel leaks.
also to isolate the vessel from the pad, clearing air/gas trapped.
E.R.

.........Yes and also....


You do not want the repad to be a pressure vessel itself. The repad thickness is likely not suited for the full operating pressure and if the weld leaks the resulting (over) pressurization of the repad could cause it to fail and become an unidentified flying object - not a good thing.

Regards, John.