Direction of flow through valves
Direction of flow through valves
(OP)
Dear all,
Please help a beginer!!!!
My question is:
Are there types of valves that are stricly directional or stricly unidirectional? Or is it that every type of valve can be both depending on the specific design? i.e. are all butterfly valves directional? are all ball valves uni-directional?
Thank you in advance!
Please help a beginer!!!!
My question is:
Are there types of valves that are stricly directional or stricly unidirectional? Or is it that every type of valve can be both depending on the specific design? i.e. are all butterfly valves directional? are all ball valves uni-directional?
Thank you in advance!





RE: Direction of flow through valves
- valves labeled "block valve" (e.g., floating ball, trunnion ball, gate, plug, or butterfly) are bi-directional
- valves intended for control can either be strictly uni-directional (e.g., Fisher V-Ball, pressure regulators, back pressure valves) are strongly uni-directional. Some control valves (e.g. manual globe valves) have a preferred direction but reversing the flow is not a huge issue.
- Check valves are uni-directional.
Some people sell butterfly valves for control. I've used a few and have never been at all happy with their linearity (i.e., a 5% increase in valve position will give you 10-30% more flow in the first 20% of travel and <1% more flow in the last 50% of travel). Even the fancy double (and triple) eccentric valves have crappy linearity. I only use them when I take over a project that already has them and I can't talk them into throwing them away.David Simpson, PE
MuleShoe Engineering
Law is the common force organized to act as an obstacle of injustice Frédéric Bastiat
RE: Direction of flow through valves
RE: Direction of flow through valves
JK