Mercer Valve Pressure Relief Valve 91-12N23EA7XM

Warning: This procedure requires trained personnel!

Are two pressure gauges available for testing?

Are the gauges reading identical values within their respective tolerances?

Select the type of the first gauge

Select the type of the second gauge

Does the analog (dial) gauge respond to pressure quickly and give accurate readings?

Are quick pressure increases seen on the digital gauge readings?

Does the test gauge have at least 0.25% accuracy over their full scale?

Is the portion of the gauge used selected so that the tolerance of it is more stringent than the set pressure’s tolerance?

Warning: This procedure requires trained personnel with PPE!

PRV placed in arbor press upside down

PRV's set spring has initial tension

Rod placed through the inlet and touches the disk

Rod sized to fit in the inlet base without damaging the seat or touching the side walls of the nozzle insert

The lift is the measurement of the displacement of the disk from the closed position to the mechanical stops at the fully open position

Shaft of the arbor press pressing against the rod sticking out of the valve inlet base

Apply slight force using the arbor press and measure the displacement of the arbor press shaft

This measurement will be the PRV's lift

Warning: This inspection requires trained personnel with PPE!

Set pressure of the valve verified?

Enter the set pressure of the valve

Contact Mercer Valve Co., Inc. for proper leak pressure and specification for the valve

Pressure held steady during the test?

Any leakage observed during the test?

If leakage is observed, the valve should be removed for further testing

Select the method used for testing leakage

Mobile testing units are similar to offsite testing

The valve is removed from the application

This enables a thorough inspection

Mobile testing units can save time because transporting the valve isn’t necessary

Mobile test units are often not set up to test all types and sizes

The testing equipment on a mobile test unit can vary

Some mobile test units have test stands similar to an offsite test stand, allowing for larger valves to be tested accurately

Other mobile test units are set up only for smaller valves

In each case, the limitations of the test stand should be documented and the test stand should only be used for the sizes and pressure that it is designed for;

Warning: This procedure requires trained personnel with PPE!

Valves transported to the shop?