Issues with stop valves
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I would like to ask whether this stop valve can be used in reverse. If so, what are the advantages and disadvantages of that? Could that expert give an explanation?
No, it’s not possible; you need to start low and end high. If you do the opposite, it will be starting high and ending low.
It cannot be used in reverse; stop valves have a direction
Anyway, sometimes we install it backwards, and the design institute will have us adjust it
If installed in reverse, when the valve is closed, the packing serves as an external seal; if the pressure of the medium is high, prolonged exposure to such pressure may cause damage to the packing. Of course, this problem does not arise when the valve is open. When installed correctly, it is the valve stem that provides the sealing function, and any leakage that occurs is internal leakage, which is relatively safer. Additionally, the force required to open and close the valve differs in these cases
Take a look at these posts: http://bbs.hcbbs.com/forum.php?mod=viewthread&tid=804302 http://bbs.hcbbs.com/thread-334001-2-1.html http://bbs.hcbbs.com/thread-890859-1-1.html
We are aware of this, but what we require here is installation in the reverse direction. We would like to ask how exactly it should be installed – whether installing it in reverse gives better sealing results than installing it in the normal direction. Installing it in the normal direction might lead to internal leaks, while installing it in reverse creates higher pressure; could this result in better sealing performance?
It can’t be used in reverse; stop valves have a direction – what an imaginative idea
In any case, the casing can improve internal sealing, but it adds an additional external seal, increasing the possibility of leakage due to pressure buildup
Well, in other words, it can be used in the reverse direction when the pressure is low. But what level of pressure is considered acceptable? Here, the pressure is around 1 MPa; I’m not sure if that will work. I wonder just how high a pressure this gasket can withstand
I think it can be used the other way around if there’s low stress