Can a stop valve be used in reverse?
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In terms of the process, padding the distillation tower is to be carried out through a certain line, and this can only be done by flowing in the reverse direction through one of the tower top outlet lines. There are control valve assemblies on these lines; is it better to use flow control valves for this purpose or shut-off valves? The process does not meet the conditions for removing the valve.
It should be fine to operate the stop valve in reverse temporarily once
Are there any materials and standards in this regard?
Of course, the stop valve must be installed in reverse, depending on the operating conditions to which the valve is subjected. If the closing torque required for the stop valve is too high, reverse installation can be considered, as this can reduce the opening torque required by the electric actuator. But every advantage has its disadvantage; when installed in reverse, the valve’s packing is constantly under the force of the medium. It’s also normal for there to be high pressure on the inlet side and low pressure on the outlet side; many systems under high pressure operate this way, as it is the pressure of the fluid that helps with sealing. For balanced globe valves, use high inlet and low outlet; for unbalanced globe valves, use low inlet and high outlet.
If a globe valve is chosen, it is necessary to consult the manufacturer; a change in flow direction requires a valve design that supports this
Since there is a valve assembly, close the valves before and after the flow control valve, then reverse the direction of the control valve! If it is used occasionally in reverse, it can also be employed for a short period.
It’s not that strict; if the conditions aren’t too demanding, reverse engineering for a short period of time won’t cause any problems
If reverse flow is indeed required, then choose a high-inlet/low-outlet stop valve; for sizes of DN200 and above with PN16 pressure rating, a high-inlet/low-outlet type can be used； Generally, something temporary and ordinary will do; it’s just a bit harder to turn off. . . .