Difference between external and internal pressure tapping for self-acting pressure control valves
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As the title suggests, could everyone please explain the difference between pressure tapping inside and outside a self-acting control valve?
Is a pressure tap type also called a stand-alone control valve? Study*Study*
What he means is that taking pressure from the pipeline is external pressure sampling, right? Currently, for ease of installation, pressure tapping is done on the valve body to avoid connections between them. However, for better regulation effects, it is recommended to take the pressure reading from the main pipeline, where the pressure is more stable. Self-acting control valves have poor adjustment accuracy, so there’s no need to insist on using them; sometimes it’s better to employ a manual valve for adjustment in such processes. I also really dislike self-powered ones.
The difference between internal and external pressure sampling in self-acting control valves lies in the method of taking pressure samples: one takes the samples from within the pipeline, while the other takes them directly from the valve body.
A self-acting mechanism is inherently an unreliable form of regulation. I have come across FISHER valves with external pressure tapping, which are very inconvenient.
Oh, I see now. I previously thought that what the original poster meant by \"internal pressure extraction\" was pressure extraction from pipes. External pressure extraction means obtaining pressure from another place. Hehe, I just now realized that internal pressure measurement refers to taking pressure readings inside the valve, while external pressure measurement involves taking readings from the pipeline.
Internal pressure sampling involves taking pressure readings inside the valve, while external pressure sampling involves taking readings from the pipeline*
Internal pressure sampling involves taking pressure readings inside the valve, while external pressure sampling involves taking readings from the pipeline
The difference should not be significant. I think it’s better to take the pressure from the pipeline, as the pressure there is more stable
Internal pressure tapping is prone to clogging; it depends on the medium.