Mercer Valve Pressure Relief Valve 91-17E51V05I1

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 without damaging the seat or touching the side walls of the nozzle insert

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

Measurement of the displacement of the arbor press shaft using a dial indicator

Enter the minimum lift for certified PRVs from NB-18 publication

Warning: This inspection requires trained personnel with PPE!

Seat inspected for cuts and abrasions

Seat polished and restored if minor scratches or abrasions are present

Seat replaced if deep abrasions and cuts are present

Spherical surface portion that engages the seat is clean and smooth

Spherical surface polished if minor imperfections exist

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 procedure requires trained personnel with PPE!

Valves transported to the shop?

Ensure all testing concerns are addressed: volume of pressure, valve simmer, pressure losses to the gauges, and supply line pressure

Note: The main disadvantage in offsite testing is time. Ensure to plan accordingly.

Enter the capacity below the valve when setting for gas/vapor valves (in ft³)

If excessive warn is observed during the test, a larger volume is required

Enter the volume of the test bench for liquid testing (in ft³)

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 from corrosion or debris

External Surface free from damage

Valve Tag information corresponds to service conditions

Valve passed the visual inspection

Issues found during the inspection