Valve installation issues
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When installing valves for olefin separation, gate valves have no directionality, while globe valves do have directionality; however, gate valves used in cold areas do have directionality. The hand valves installed before and after control valves should be oriented toward those control valves. Could someone please explain why this is the case?
I have seen check valves with a defined flow direction used at the inlet and outlet of safety valves, with the flow always directed toward the safety valve. My understanding of this is that when the safety valve is activated, the medium exerts a force on the valve core to close it, ensuring that the valve shuts properly.
Gate valves can achieve good sealing at either of their two seat surfaces, so the direction in which they are installed doesn’t matter. Although globe valves have an orientation indicator on their body, they can actually be installed in either direction; as long as they are manufactured properly, installing them in either direction should be fine. However, for large-diameter or high-pressure valves, it’s better to install them according to the orientation indicator. The need for a specific direction in low-temperature gate valves is aimed at addressing the issue of pressure release from the sealed valve chamber, and this is achieved by drilling holes in the sealing surface of the gate to allow pressure to escape. I can’t understand this last question. Is the orientation behind the valve always like this?
Thank you! What does it mean to relieve pressure in the sealed valve chamber? I’m not quite sure. One last question: the manual valves before and after the control valve also have a directionality, and they are installed so that their direction is toward the control valve; I’m not quite sure about this either
There are valves with two sealed valve seats, such as gate valves and ball valves, which have a sealed space within their valve chamber. When used with low-temperature media, these media expand when the valve is not in use, and this could cause damage to the valve. Therefore, AOI6D requires a self-pressure-relief function: when the pressure in the sealed valve chamber rises to 1.33 times the nominal pressure, the valve seats release pressure automatically.
If it involves drilling holes in the check valve chamber, then there’s no need to consider direction when installing it, as pressure can be released in either direction. Do you have any pictures of the valve? Please send one so I can share it