But isn't that the job of the isolation joint? Besides steel is a conductor not a capacitor like A1, so wouldn't the static just move with the product? I know Shell blew up some AI tanks at SFO due to static at the discharge nozzle inside the tank, but that was before they used additives to...
I purposely did not mention anything to get an unbiased opinion. I am not sure that I understand how static in a product would be mitigated by a spark gap protector. Perhaps you can enlighten me.
I would not be concerned about mainline block valves leaking. First they are welded into the line and many, like Cameron and Borsig have all welded bodies. The likelyhood of pipeline dammeage, i.e. is there any traffic on the river, and the environmental impact of a leak should be your primary...
My pipeline comes above grade in a plant. Between the overbend and the pig trap I have an isolation joint. Does the isolation joint require a spark gap protector ?
The offshore pipelay contractor used a manual weld to weld a 12-inch barred tee to the pipe and then the ILUC to weld the next joint to the tee. The tee was made from half in pipe and the pups were made from 0.438-inch. The pipeline is 12 x 0.438. The contractor's reason for the manual weld...
Dave, you maybe confusing design pressure with test pressure. The B31 series allows 10% over design to account for transients. Afterall the Barlow Hoop stress is overly conservative being based on the OD when the actual hoop stress is based on the ID.
Remember the hoop stress for design...
Thanks all,
The pipeline system was successfully flooded, gauged and hydrotestedand the contraol valves were reinstalled this morning.
Regards,
Elijah C
Thanks Vzeos,
This plant is overseas and built to B31.8 2007 ed. All valves, flanges and fittings are normally all hydrotested together, in this case to 1.4 times MAOP. However, control valves are not covered by API 6D, so we normally install a dummy spool prior to FGT operations and install...
Thanks Patricia,
That was the first thing we did, unfortunately the vendor wasn't any help. Hence my question in this forum.
Industry standard seems to be to replace them with a spool during pressure testing, which jives with my experience.
Chris
Many thanks for the input. It reinforces my experience. By "control valve", I am talking about the traditional type of valve with a sliding mechanism. So I agree, it's not necessary to remove other types of valves not prone to getting jamed by particulate matter.
In the past we have hydrotested systems prior to installing control valves by installing a short spool in lieu of the valve. I have a contractor who is insisting that this is unnecessary. The system is ANSI 600#, Class Location 3, per B31.8 2007. The design pressure is 1440 (not 1480)and the...
It looks like I have been overlooking something. B31.8 allows for golden welds for tie-ins in lieu of a pressure test. Can this hot tap tie-in be treated like a golden weld?
I am going to hot tap into a gas pipeline. What codes govern the hydrotest pressure required? The following is what I have read and does not appear to provide an answer.
1. ASME B31.8 is quite clear about hydrotesting new pipelines and re-hydrotesting existing pipelines to operate at a higher...
Guys,
We specified 36-inch R98 RTJ gaskets. These are octagonal per ASME B16.20. Our client managed to purchase KaMOS oval gaskets. B16.20 does not list oval R98, only octagonal. Can we use oval or are we SOL? This is for subsea 600# sweet gas service.
Chris
