Problem in ATOS Make Proportional Pressure Relief Valve

What sort of system? How is the valve being controlled? What is the nature of the fluctuation? What is the purpose of the valve? What are the operating parameters of the valve? Is it possible the valve is overcorrecting? How was the valve sized? What tests have you performed on the valve?

Two things come to mind; improper application and improper tuning. It is imperative that you have an intimate knowledge of the process conditions to determine what is causing the problem. So how about more information about the use of this particular valve.

Of course you need to rule out that the unit itself may be failing/faulty by stating whether this was a replacement unit or that there were changes in the process stream. Has it ever worked right? Have you swapped out the unit with an identical known good one? Most importantly have you contacted the manufacturer for further advice?

Could you describe (a sketch would be the best) the system for which you use the valve ?

According to the valve concept there are at least 2 possible reasons. Your information could help to pinpoint the most probable one and a correction path.

Please describe the outcome of the telephone call that has taken place with the equipment manufacturer.