Problems with PSA valve installation
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This post was last edited by wcq1010 on 2017-5-20 at 20:42. Under normal circumstances, normal valves are installed with the inlet at a lower level and the outlet at a higher level, but this is not the case with PSA valves. What principles guide the installation of such valves?
The molecular weight of gases is generally lower than that of air; the molecular weight of air is 29. Given this, most gases tend to rise, which is why they move upward and downward. I’m not sure if it’s right. :lol
If anyone knows, please let me know!
It doesn’t seem to have much to do with the molecular weight of the gas. Generally, the principle of lower inlet pressure and higher outlet pressure is followed. For pressure equalizing valves, their installation direction is always opposite to that of the gas inlet, so as to maintain the pressure inside the tower
Hi HAIYOU on the 4th floor, “For pressure equalizing valves, the installation direction should be opposite to the gas inlet direction.” I’m not quite sure what you mean by that. After all, the same average rising and falling processes in the same tower share the same pipeline; thus, with gas inlets on both sides of the valve, how can the installation direction be determined?
The voltage equalizing valve has few requirements regarding its installation direction; the main thing is to ensure that the valve remains under vacuum. During process design, it is necessary to take into account the scenario where a valve failure occurs – in such cases, the valve should not be pushed upward. That is, even if the tower is not in a vacuum state, the pressure inside the tower will keep the valve in place, preventing the risk of it being pushed upward
I have also noticed that many of the PSA valves here are designed with flow from high to low. At present, most of the valves here are globe valves; for valves with a diameter of DN100 or larger, a design with flow from high to low is used to ensure good sealing performance, while smaller valves can still be equipped with a design that allows flow from low to high. Additionally, the valves that arrive are all marked with the flow direction of the fluid, so the installation principle still follows the direction indicated on the valve.
In my opinion, the installation direction is primarily determined by the practical aspects of the manufacturing process. Take the evacuation valve as an example: the pipeline through which evacuation takes place is always under negative pressure. To ensure the valve’s airtightness, having high pressure on the inlet side and low pressure on the outlet side allows the pressure inside the tower to help seal the valve further. I’m not sure if this is correct!
Reply to 9# Wang Wei of Charnon: Whether high or low, it’s all horizontal!
If anyone knows, please let me know!