Internal is leakage around the valve seat or through the closure member when the valve is closed. Internal leakage is normally contained within the piping system. Such leakage can be external when a valve is used to dead-end a pipe. Internal leakage is checked with a seat leakage or a closure test. The allowable leakage rate depends on the valve test standard.

PROVIDES FLEXIBLE AND INSITU INSPECTION…

ENEFIN supports our customer with systematic, methodical inspection and analysis for suspect process valves and PSVs that internal passing or fail in closed position.

We conduct the survey using Digital Ultrasonic and Acoustic Emissions (AE) monitoring techniques to detect and locate internal leaks across valves and pipes under pressure.

What ultrasound? Ultrasonic analysis has a wide variety of uses. There are numerous examples of applications for detecting failure modes on mechanical, electrical and stationary equipment. The technology is powerful and flexible in that numerous failure modes can be detected on different types of components.  

A Steam passing through a valve that’s supposed to be closed. The leak path will generate a turbulent flow. The leakage between the valve and the feeding insertions will generate a turbulent flow, which will generate a high frequency ultrasound, which this unit will pick up, such as cage, valve, globe, gate, butterfly, any type of a valve. The instrument that senses the ultrasound can detect very low ultrasonic levels, to very high ultrasonic levels. You have a sensitivity adjustment to make the unit very sensitive, and to be able to detect a leak level of one time to minus two, or a very large leak. The thing about it is, is understanding what leak level you’re picking up. Depending upon the severity of the leak the plant has been able to reduce downtime dramatically.