Prv - Bermad

[punkster]

Firstly hello this is my first post. My aim is to improve my knowledge of pressure reducing valves. I have been trained on cla-vals but obviously there are many variations in type of prv and the actual operation it performs.

Although I have had some training I am far from competent!

My question is I have come across a bermad with a prv pilot that then connects into a x-pilot on the same pilot rail. Why two pilots could the x-pilot not perform both functions?

Look forward to any comments.

Punkster

Water distribution

 

[EnergyMix]

A drawing might help others better understand the question. There's a lot of reasons that there might be two different pilots and I hate speculating. Also have you looked for any sort of a user's manual? Some companies have them available on the web.

Want to know the do's and don'ts of Eng-Tips? Read FAQ731-376.
English not your native language? Looking for some help in getting your question across to others or understanding their answers? Go to forum1529.

 

[gerhardl]

Some PRVs (also Bermad) have closed circuits as an option, where two pilots in seria are used, with a complete sealing between the proces fluid (pilot one) and internal working pilot fluid (pilot two).

This is a solution to prevent the 'unwanted' characteristic of the process fluid to penetrate into the working parts of the valve internal steering system. This could be temperature, corrosivity, radiactivity leaks or other.

Is this the case?