TM 5-4310-393-14
4-18.
PRESSURE MAINTAINING VALVE.
This task covers. A Adjust B. Replace
Tools:
Materials/Parts:
Tool Kit, General Mechanic's Set
Non-ionic Detergent, NSN 7930-00-282-9699
Distilled Water, NSN 6810-00-297-9540
Equipment Conditions:
Compressor Operational
Pressure Purged From System
NOTE
The setting of the PMV at the factory
is 2000 psi (138 bar)..
A Adjust
1.
To determine if the Pressure Maintaining
Valve PMV is properly adjusted:
a. Depressurize the final separator and
purification chamber by slowly opening the manual
purge valve.
b.
Close the purge valve and then start
the compressor with the delivery valve open.
Figure 4-13. PMV
c.
Observe the final pressure and note the pressure at which the PMV opens (air is delivered) If the
pressure is not within 2000 ± 200 psi (138 + 14 bar), readjust the PMV.
d.
To readjust the pressure setting loosen the locking ring (Figure 4-13, Item 2), and using a hex key,
turn adjusting screw (1) clockwise to increase pressure, counter-clockwise to reduce pressure
B.
Replace.
1.
Replacing the PMV.
a.
Open the purge valve and release all air pressure from the system (paragraph 23)
b. Disconnect the air lines from the PMV and install a new unit in its place. Soap test all fittings for leaks
c. Adjust new valve as in steps 1, a through c.
4-19.
INTERSTAGE PRESSURES.
This task covers, A Check B Install C. Test
Tools:
Materials/Parts:
Tool Kit, General Mechanic's Set
Cloth, Lint-free NSN 7920-00-044-9281
Pressure Gauge, Test (P/N 057491
Detergent, Non-ionic NSN 7930- 00-282-9699
Pressure Gauge, Test (P/N 057492)
Water, Distilled NSN 6810-00-297-9540
Equipment Conditions:
Unit Shut Down
4-31
