How to Identify Passing Steam Drain Valves/Vents and Steam Traps


Thread Starter



I have some idea about how to identify a passing valve

Like Detection of a passing valve using the Joule-Thomson effect principle through the valve: This principle consists of identifying a lower temperature downstream of the valve compared to the temperature upstream of the valve. This method can be applied with a thermal gun.
But I am not convinced with this way..Even I found some live steam from the blow down tank.

Listening through audible sound also getting difficult because many other machinery in service in the vicinity.

Does any one practicing the best method at their power plant to identify the steam leaks through passing drain valves and steam traps.

Our Power plant is of capacity 2000 MW and I am really worried of losing the live steam and more amount of energy. I am working in performance department, I am looking for the best and efficient method to find the steam leak drain valves/vents and steam traps.



We have successfully found leaking steam traps/air leaks, etc using an ultrasonic detector. It's surprising what you hear in the ultrasonic range....its another world "up there"!


Hi sir..

thanks for your reply. can you also able to identify passing steam drain valves with ultrasonic detectors...

what range ultrasonic detectors are required to find out superheater steam passing drain valves?

If so please provide us with the product specifications and manufacturer details. we would like to order one or two ultrasonic detectors to eliminate this problem at our site. what could be the approximated cost for ultrasonic detector?
My experience in this issue, you know if there is any raise in the condensate on the staem line you will find a hammering on the steam Lines. we used to crack (very little) open the drain valves once a day for a period of 15 minutes is the best practice we found.

Regarding using ultrasonic device, is it online or portable one? Is it connected to another drain valve? How about the cost effectiveness?

Best luck
We have found leaking valves using a portable ultrasonic detector made by UE systems. We set our detector in the 25khz range and it is very simple to hear a valve that is leaking, especially when you can compare multiple valves in the same area.