Mercer Valve Pressure Relief Valve 91-12GP2EA7UD

Warning: Ensure the valve is not pressurized before starting the inspection

Cap and Seal Wire in good condition

Flanged Connections in good condition

Threaded Connections in good condition

Outlet free of corrosion or debris

External Surface free of damage

Valve Tag information corresponds to service conditions

If any of the above checks fail, the valve is deemed dangerous to test and should be replaced or repaired immediately

Sign off on the visual inspection

Warning: This procedure requires trained personnel with PPE!

If valves are not removed, stop the procedure and report to the supervisor

Pressure losses to the gauges checked?

Proper assembly of a test bench is crucial in limiting these effects

Note: The main disadvantage in offsite testing is time

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

Is the analog (dial) gauge not liquid filled?

Does the digital gauge respond to quick pressure increases?

Do the test gauges have at least 0.25% accuracy over their full scale?

Is the tolerance of the used portion of the gauge more stringent than the set pressure’s tolerance?

The following general procedure is recommended for the disassembling of a 9100 Series PRV

Non-standard or “special” configurations are possible and these instructions may not be reflective of them

A special configuration is indicated by a special code at the end of the PRV’s part number

Always make sure there is no pressure in the system prior to removing a PRV

The 9100 Series contains several different orifice sizes

For most C to G orifices, the valves are bottom entry type with the bonnet integral to the body cavity

These valves have a removable inlet base

Larger orifice sized valves are top entry types and have removable bonnets

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?