Fellows, Cv is a coeficient factor that has no units! The units associated with Cvs are the base for which a flow factor is determined. These units do not carry to the Cv factor.
What can have a bearing on the value is the interior shape of the flow passage and valve length. Think of a...
Are you talking about a 3way ball valve? If so this type valve is NOT a control device. The valve is designed to change flow direction only. The valve port through the ball is the same a 90 degree elbow in a pipe system. This type valve should be stroked fully i.e. full 90 degree rotation...
Not sure where the question of piggable or not came from as this has nothing to do with the origianl question.
The question is what should the end bore be at the butt weld end. The bore of the valve through the ball should be in accordance with Table 1 of API 6D or 633mm dia. (24.9" dia)min...
This one is simple. 4" class 1500 flange has qty 8 - 1.25" dia. bolts. You have your materials backwards. Bolt material is B7M (softer than B7) anf the nuts are 2H. Based on the tensile stress you wnat the torque for each nut is 500 to 750 ft-lbs. Of course the torque is applied in 25%...
You should seek the answers you are looking for from the manufacturer of the valves in question. You must make certain who you talk with the designers not just a manufacturer who copied the design of others. The original engineers can tell you exspected leakage rate from the bleed connections.
metengr,
I have a cleint who has been furnishing class 1500 cast steel, A216 - WCB, valves w/BWE w/pipe pups of WB36 pipe material welded to each end. The WC36 material is a plate material to a DIN spec 1.6368 (now EN 1.6368). This material is very close to the chemistry of A533 plate. The...
I am seeking information on a cast material that is equal to ASTM A533 grade b plate material. A533 provideds the chemistry and HT for plate but I would like to have an equal in a cast form. Does anyone know of a casting spec equal to the plate spec or have info on HT?
Are you certain it is erosion? Have you checked the flow conditions and assured yourself that there is no cavitation taking place that is causing the damage?
Neither answer is complete.
1. Because the ball and stem in a ball valve are susspended on non matalic parts , i.e. the seats and stem seals, there is a possibility when cycled a static charge can build on the ball-stem. Ball valves usually have a method to maintain a metal-to-metal contact...
There must be some one in Italy with the number of valve companies over there. Suggest you seek out an Italian valve manufacture and ask them for a recomendation.
Dave Fitz got it right. With high pressure and temperature valves a method should be used that will prevent the gate valve bonnent area from be overpressurized from fluid being trapped in the neck and thremal increase that can cause fluid expansion. This can lead to a very danerious condition...
Several materials will work in steam. Much depends upon what the actual conditions are. The best choice for general saturated steam is carbon steel, both cast or forged.
Yes, Boiler non-return valve (also referedto as a Stop Check valve) is a check valve that can be closed. This valve has a disc and stem but the stem is not fastened to the disc. When desired the stem can be turned down to shut off flow. But when the stem is retruned to the open position the...
Most of the ASTM material specification permit weld repair to a casting to repair casting defects. There is no standard or specification that states how many repairs or the severity of defects tha can be repaired. This is usually left to the casting buyer as to what limit he will accept from...
Does anyone know of a good low cost control valve sizing program available? If so please provide details. If not, know of any good engr/programer who understands control valves, fluid flow, sizing and can write programs? If so let me know.
Thanks for the help!
Any leak rate must include volume vs time. General industry standards such as API 598 and MSS SP 61 give acceptance leakage as a rate.
Bubble tight valve seats should only be expected with new valves and on valves as they are tested under good control. Bubble tight or zero leakage should...
