The function of a stop valve
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After researching a lot of information, I found that there are completely different opinions regarding the uses of globe valves. For example, some say it can throttle and regulate. Some say it cannot. Who to believe? Which expert could please explain in detail?
Classified by purpose and function: Control valves, which are primarily used to regulate parameters such as the flow rate and pressure of a medium, including control valves, throttle valves, pressure reducing valves, etc； Shut-off valves are primarily used to stop or allow the flow of media, including gate valves, globe valves, diaphragm valves, ball valves, plug valves, butterfly valves, plunger valves, and ball-plug valves
Can a stop valve be used for throttling and regulation? It can be understood in this way: the degree to which the valve is opened can affect the flow rate. To be more precise, it cannot be used for that purpose, as it’s difficult to control the flow rate accurately depending on the degree of opening of the valve. It’s just my own understanding; if there are any mistakes, please point them out
Definition: A globe valve is a valve that closes in a downward direction; its disc is moved up and down along the axis of the seat (sealing surface) by a valve stem. Characteristics: Globe valves have the ability to regulate flow rate and pressure to some extent.
Each issue should be analyzed on its own; it can be said that valves can all regulate pressure, but not all valves can regulate flow. Depending on the operating conditions, the function of the valve also varies. Most pneumatic control valves use globe valves as their valve bodies. The differences in the internal components result in completely different outcomes.
The closing element of a globe valve is a plug-shaped disc, whose sealing surface is either flat or conical; the disc moves in a straight line along the centerline of the fluid. The type of movement of the valve stem – (general term: hidden stem) – also includes a rising and rotating stem type (general term: exposed stem). A globe valve is a valve in which the closing element (valve disc) moves along the center line of the valve seat. Based on this manner of movement of the valve disc, the change in the valve seat opening is directly proportional to the stroke of the valve disc. Due to the relatively short opening and closing stroke of the valve stem in this type of valve, as well as its highly reliable shut-off function, and because the change in the valve seat orifice is proportional to the stroke of the valve disc, it is highly suitable for regulating flow rate. Therefore, this type of valve is very suitable for cutting off, regulating, and throttling
This post was last edited by yuchenchf on 2014-4-14 at 11:16. I’m not very familiar with this either