Ariel JGJ Series, Technical Manual

Page: 105 / 141

F
OR
M
ODELS
: JGW, JGR
AND
JGJ S
ECTION
5 - M
AINTENANCE
1/01 PAGE 5 - 33
Valves - Maintenance
Ariel uses valves manufactured by Hoerbiger Corporation. Before servicing any valve refer
to the correct valve assembly drawing and parts list and Hoerbiger'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
springs may be required.
The suction valve must be selected on the basis of operating suction pressure and the dis-
charge 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 Ariel in Mount Vernon, for assistance in valve selection.
Valves - Reassembly
1. The 1/32 inches (0.8 mm) thick soft metallic flat gasket should be coated with an
anti-seize lubricant. It can then be either inserted into the valve pocket or stuck
onto the valve. In either case, care must be taken to keep this gasket from falling
into the gas passage.
2. The retainer keeper is a plastic thumb screw in a threaded hole in the bottom
valve retainers. This should be screwed through just far enough to provide fric-
tion so that bottom retainers will not fall out while the cap is being installed.
3. Using the Valve Tool illustrated in Figure 7-1: on page 7-3, the valve and the
retainer may be inserted into the pocket together. When installed correctly, the
distance from the outer retainer face to the surface of the valve boss on the cyl-
inder will be 1/8 inches (3 mm) shorter than the length of the nose on the valve
cap.
4. Inspect the valve cap O-ring for cuts or gashes and replace it if necessary.
Lubricate the O-ring and the nose of the valve cap. Some high pressure cylin-
ders use a soft metallic wire gasket in lieu of the O-ring design. Insert the cap
and tighten the bolts evenly to the recommended torque in Table 1-11 on page
1-15. See “Bolt Tightening for Valve Caps” on page 5-34. If the assembly is cor-
rect, the distance from the underside of the cap to the valve boss surface on the
cylinder will be 1/8 inches (3 mm).
NOTE: BE CERTAIN ALL PARTS, GASKET FACES, AND MATING SURFACES ARE
ABSOLUTELY CLEAN AND ALWAYS USE CLEAN, FRESH OIL ON THE
THREADS BEFORE REINSTALLING BOLTS.