The preference of butterfly valves in oil & gas is weight, if this is a oil plattform or a ship it is important and if you have lack of room or you are in a compact skid assembly.
Concentric valves are little hard to do a good elastomeric seat caused by risk of deformation during operation. High...
You will have problems with PTFE and the carbon steel as you said it has. A good carbon steel for you would be the 9% nickel alloy, very used for very low temperature. Try to check it. Take a look for gasket for low temperature that maybe your client has good specification. I used PTFE very well...
Easy answer for you. SDV, BDV and any on-off valve that receive an actuator goes to Instrument Departure of Engineering while the manual valves are in Pipeline Department. This is not exact your company but I believe it is similar. Instrumentation People are used with really control valves used...
Pay attention to last edition of API 600 that void the TRIM 1. The reason is galling problem caused by two stainless steel faces under great face contact pressure. Some manufactures are offering a upgrade of API 600 specially if you are buying a valve with API stamp.
You need to have in mind all necessary tests to assure you no fail during the life of the valve.
Backseat, internal relief pressure device, fire test, torque to close and torque to open, NDT and so on.
Some of them are on type approval test, others are default and others you have to ask.
As trvalve said and I believe that it is not difficult long time ago a valve to be made without any standard. Nowadays company does what client ask to keep their profit and they deliver warning that it is not according to standard.
I believe that everybody here would like a picture of this valve...
If this control valve is for flow control, or in other words, it does not close, the sandblast will not affect its thightness, anyway it is important protect inner part. Atfer sandblast you may do a water flow to test or to wash.
About loose thickness, it is possible with a non trainned operator.
Dear All,
Thanks for your answers. Looking for a site of any organization that treats about the worker health in these kind of installations I found this OSHAS link: https://www.osha.gov/dsg/guidance/perc.html it is not everything that I need but it is a initial guide.
Thanks for your reply moltenmetal, anyway and first to begin any job I am looking for a association or a society that specifies or have the best practices for these service. After this trial I may begin my point of view to do a safe lay-out including fugitive emission, aeration and so on.
Carcinogenic fluids requires a lot of care during piping and equipment assembly as the fugitive emission test. Some approved equipment, valves may be very close among them and create a concentration of this fluid emission getting a not approved instalation. Does exist any society similar as...
I would say OK if necessary to reach the pressure on shell, shell with botton and so on. Only to check the welding and ANYPOINT that receive a welding heat I prefer the negative air test. This test develop a higher differential pressure than the positive air test. It is safe for everybody. The...
Much better than positive air test is to do negative air test. You will do it outside the roof tank, the negative pressure is higher than a positive air test, it is safe and so on. The parts impossible to do negative air test I suggest you to do capilarity test. I kick procedure would be to wet...
Unfortunelly at this moment I am not with my specifications in hand but there are tungsten carbide, hard chrome. Try the site of Praxair to find anything else.
Carcinogenic fluids requires a lot of care during piping and equipment assembly as the fugitive emission test. Some approved equipment, valves may be very close among them and create a concentration of this fluid emission getting a not approved instalation. Does exist any society similar as...
I believe that you need a rusting prevention and I don't know the place of your construction or use. Anyway, only zinc plated is not satisfactory for marine enviroment. I prefer Zn-Ni for this case. In case of bolts and nuts the only problem is not corrosion resistance but abrasion resistance...