Mercer Valve Pressure Relief Valve 91-12I12YA7CJ

Warning: This procedure requires trained personnel!

Are two pressure gauges used 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 gauge respond to pressure quickly and give accurate readings?

Are quick pressure increases seen on the digital gauge readings?

Do the test gauges 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 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?

Choose the method used for testing for leakage

Zero bubbles observed for one minute in API 527 test?

Warning: This maintenance check requires qualified repair personnel!

Is the PRV correct for the application?

Are there any apparent problems with the PRV?

Is the nameplate information correct?

Is there any damage to the valve?

Are there any issues that would keep the valve from opening or inhibit flow?

Are there any problems found during the visual inspection?

Warning: This inspection requires trained personnel with PPE!

The set pressure inspection is performed in accordance with the ASME BPVC.

The set pressure tolerance is calculated based on the actual nameplate set pressure.

The set pressure test should be performed before and after any repairs.

The correct fluid for testing has to be used to achieve accurate results.

Setting procedures should be in accordance with ASME PTC 25.

The rate of the system pressure increase should be slow when the pressure is within 15% of the set pressure.

The procedures for testing set pressure are as follows.

Check the set pressure definition from NB-18.

During the visual inspection, the pressure relief valve is checked for any potential issues that may restrict the operation of the valve

This inspection will be performed with the valve still assembled but the valve should not be pressurized for the safety of the person performing the inspection

Corrosion and damage to the valve are some of the common problems found in the visual inspection

Some of the items that should be checked in the visual inspection are as follows

Cap and Seal Wire - The valve cap and seal wire should be checked first on all inspections

These parts prevent adjustment tampering

On the seal wire, there is a pressed security seal that has an impression on it to indicate the certified company that last adjusted the set point the valve

When this seal wire is cut or removed, it indicates that someone may have adjusted the set point or altered the valve

This voids any warranty the valve had