How should “valve closed upstream and downstream pressure” be arranged in Chinese?
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This post was last edited by lily99 on 2012-7-30 10:49. For On/Off valves, process specifications will contain: Applicable flowing conditions with minimum valve closed upstream and downstream pressure. I would like to know whether it refers to pressure or pressure difference, and how should it be phrased in Chinese?
The mother valve is closed – what does \"maximum pressure upstream/downstream when the valve is closed\" mean? I still don’t understand what’s being said; I only know about \"closing pressure\" and \"upstream/downstream pressure\", but I’m not sure what the combination of these terms means
What type of on-off valve is this? I think it refers to the pressure difference: the maximum closing pressure at the relevant flow rate
Can it be understood as inlet pressure and outlet pressure?
This post was last edited by shale on 2012-7-30 at 13:35. For centrifugal pumps, when the outlet valve is closed, the pump’s flow rate is zero; at this point the pump’s head is at its maximum, which means the outlet pressure is also at its highest. In other words, this represents the maximum upstream pressure across the valve, and consequently the pressure difference across the valve is also at its greatest.
Typical specifications for pneumatic on/off valve instruments include the following details: 1: Operating pressure of 0.55 MPa, maximum closing differential pressure of 0.55 MPa； II: Operating pressure 4.22 MPa, pressure drop at full closure 4.22 MPa ； III: Operating pressure – Atmospheric pressure, maximum shut-off differential pressure of 0.2 MPa ； IV: Pressure before the valve is 1 MPa, and the pressure after the valve is 0.45 MPa ； Maximum shut-off differential pressure () ； The one you posted should be the fourth type.