Butterfly valve downstream of a check valve, will it work.
Butterfly valve downstream of a check valve, will it work.
(OP)
I am laying out some additons to a existing Natrural Gas compressor station and I am tight on space. To save space I am trying to put a butterfly valve directly downstream of a wheatly swing check valve. Both valves are 20" ANSI 300#. I am worried that when the butterfly vavle is fully open it will interfere with the operation of the swing check.
Does anyone know if there will be interfereance with these types of valve? OR has anyone seen these types of valves in this combination?
Does anyone know if there will be interfereance with these types of valve? OR has anyone seen these types of valves in this combination?





RE: Butterfly valve downstream of a check valve, will it work.
RE: Butterfly valve downstream of a check valve, will it work.
Their streamlined flow pathes prevent turbular flow and do not harm the butterfly.
Additionally they show low pressure losses and non-slamming performance.
Have a look at www.noreva.de
RE: Butterfly valve downstream of a check valve, will it work.
BTW, I do not think I could sleep at night if I used a butterfly valve for a unit block valve. My choice would be a ball valve with a backup sealant injection system as this valve absolutely, positively has to shutoff.
You should also take into consideration that the unit piping in a compressor station is normally blown down after a period of time after the unit is shutdown.
RE: Butterfly valve downstream of a check valve, will it work.
Also agree with 1969grad on isolation choice...although the butterfly will work it is a bad choice for what we know of your application...if positive isolation is needed and differential pressure on closed valve is high I recommned Orbit Valves by Cooper Cameron.
RE: Butterfly valve downstream of a check valve, will it work.
Your conbination of swing check valve and then butterfly valve would warrant a call to the manufacturers for more specific dimensions on the check valve outlet and the distance of the BFV disc protuding into the upstream piping.
One thing I didn't see anyone mention is the valve orientation. It would be advised to have the BFV shaft be perpendictular, not parallel to the check valve's hinge. Asymetrical flow patterns generated by the swing check could effect the BFV.
If this is a critical isolation valve I would agree with 1996grad on the ball valve with sealant injection system. WOM has a new valve with DOUBLE seats on both sides. This is new concept in ball valves done in gate valves for years in natural gas ie General Twinseal. To make up the longer face to face than the BFV, use a DFT in-line check valve like the WLC. These guys claim to be "Check Valve Doctors". If you give them the process conditions they will size the valve and install a travel stop that will prevent the valve from beating it self to death.
http://www.womusa.com/
http://www.dft-valves.com/