Search results for query: *

ASME B31.3 para 345.2.2 stipulates "A leak test shall be maintained for at least 10 mins." 30 minutes is a more practical minimum though.

Some fittings and valve manufacturers offer forged fittings, flanges, valve bodies etc. in Carbon Steel ASTM A105N. I realise the N suffix denotes a normalised product which has received extra heat treatment, but I am uncertain as to why the N grade should be specified. What practical benefit...

Note that minimum hydrotest pressure is 1.5 times the DESIGN pressure (not operating pressure or max. operating pressure). You may be required to compensate for temperature difference per Equation 24 of ASME B31.3. We write into our hydrotest spec that minimum hydrotest pressure will be 7.0...

"greddek" pretty well sums it all up. There used to be some nice little crimped washers available that you inserted down the bore of the socket weld fitting which ensured that the pipe didn't bottom out. They were designed to maintain that 1.6mm gap. I wonder if they are still...

Dismantling joint flanges should be specified to the same standard as any other of the flanges in the piping system i.e. ASME B16.5 or similar. I am not aware of a relaxation in any of the national piping design codes which permits otherwise.

I have some very old computer programs which have been satisfactory for calculating ASME B31.3 and B31.1 pipe wall thickness and branch reinforcement data for many years. Our new issue of computers at work no longer handle these ancient programs very well. We are in desperate need of new...

In the case of ball valves the body cavity is normally vented to the upstream side. Therefore, when the valve is in either the open or closed position the cavity will never become excessively pressurised. Venting downstream could give rise to safety issues if downstream piping is dismantled...

Go with a hydrotest every time steam is involved. I don't believe the spirit of the code was ever intended to include steam in cat. D service. Strictly speaking it is the Plant Owner's responsibility to determine what fluids will be considered as cat.D or M, although the owner can pass on this...

I would have thought that at 2500# rating you might be wanting to NDT the welds anyway. If so, then the weldolet/weld neck flange would be the prefered route.