Heavy Duty Balanced Opposed Compressors - Ariel Corporation

FOR MODELS: JGZ AND JGU SECTION 5 - MAINTENANCE
6. For high pressure applications that use a metallic wire gasket seal, the cylinder
will vent when cap screws are first loosened. Use the valve removal tool shown in
Figure 7-5 on Page 7-4 to unseat the metallic wire gasket.
7. Now the valve and retainer can be pulled out together.
8. In most cases the flat metal gasket will remain in the pocket. It is difficult to see. A
flashlight, and a small mirror on a flexible extension rod are the best tools to see
the gasket clearly. On cylinders with horizontal valves, the gasket may fall into the
gas passage. A small magnet on a flexible extension rod may help fish it out. This
gasket should be replaced if damaged.
Valves - Maintenance
Before servicing any valve refer to the correct valve assembly drawing and parts list and
valve manufacturer’s literature in the Parts Book. On the valve assembly drawing you will
notice that valves have different springing for different pressure levels. The cylinder cover
sheet in the Parts Book lists the valve originally supplied with each cylinder. If different operating
pressures are encountered, then different springing may be required.
The suction valve must be selected on the basis of operating suction pressure and the discharge
valve for operating discharge pressure. Proper valve spring selection is also based
upon the operating speed (RPM), gas specific gravity and the suction temperature of the
gas.
Contact your Packager and/or Ariel, Mount Vernon, for assistance in valve selection.
Valves - Reassembly
1. Carefully clean all debris from the cylinder and valve cap surfaces at the
1/8 in. (3 mm) nominal gap. See Figure 5-48 on Page 5-59. Be careful to keep
debris from entering the cylinder.
2. The 1/32 inch (0.8 mm) or 1/16 inch (1.6 mm) thick soft metallic flat gasket
should be coated with a thin coating of anti-seize lubricant. It can then be either
inserted into the valve pocket or stuck on the valve. In either case, care must be
taken to keep this gasket from falling into the gas passage.
3. Be sure that suction valves are installed only in suction pockets and discharge
valves only in discharge pockets. The valve pockets have identification plates,
see Figure 5-47. All valves are installed with the valve fastener(s) positioned
away from the cylinder bore. If a valve is not marked for suction or discharge, or
to verify the type, depress the valve plate by hand. It is recommended that a tool
which is softer than the valve plate material be used or care be exercised to prevent
damage to the plate. A suction valve plate can only be depressed from the
valve fastener (bolting) side of the valve, and a discharge valve plate can only
be depressed from the side of the valve that goes toward the cylinder bore. Reference
Figure 5-48 on Page 5-59.
7/09 PAGE 5 - 57