4-27. PRESSURE REGULATING VALVE REPAIR - cont.
(1) Using wire brush, remove corrosion and water deposits from threaded components.
(2) Wash all components with clean water and detergent. Make sure all water deposits are removed.
(3) Rinse components in clean water and dry with wiping rag.
(1) Inspect body (20, figure 4-19) for cracks, corrosion and stripped or damaged threads.
(2) Inspect stem (15) for cracks, scratches or damaged threads.
(3) Inspect cover bearing (6), disc retainer (11), disc guide (14) and seat (16) for cracks, corrosion
and deep scratches.
(4) Inspect all threaded piping components (figure 4-18) for cracks and stripped or damaged threads.
(5) Inspect frame (10, figure 4-17) for cracks, broken welds and bent frame components.
Replace damaged parts and all sealing components. Do not reuse diaphragm (10, figure
4-19), disc (12) or packing (17).
Assemble Pressure Regulating Valve. Refer to figure 4-20.
Ensure that anti-seize tape is applied in the same direction as the threads.
(1) Apply anti-seize tape to threads of plugs (1, 18, and 19).
(2) Install two plugs (19) in body (20).
(3) Install plugs (1 and 18) in cover (4).
(4) If removed, install packing (17) and seat (16) in body (20).
(5) Install disc guide (14) and spacer washer (13) on stem (15).
Number of spacer washers must be adjusted during assembly to prevent over compression of
(6) Position disc (12) on disc retainer (11), then slide both parts onto stem (15).