F
OR
M
ODELS
: JGI, JGM, JGN, JGP
AND
JGQ
S
ECTION
5 - M
AINTENANCE
PAGE 5-35
9.
Prior to installing the packing case into the cylinder, the end cup gasket must be
inspected for nicks and damage that would cause it to leak in service. When in
doubt, replace the gasket with a new one.
10. Prior to installing the packing case into the cylinder, be sure the gasket surfaces
in the packing counter bore on the crank end of the cylinder are clean and not
scratched.
11.
Re-install the complete packing case assembly with the oil supply point on top.
Use the rod packing bolts to pull the packing into place, but do not tighten at this
time.
12. Re-install the packing diaphragm and wiper packing.
13. Re-install the piston and rod. Follow the steps under “Piston and Rod - Installa-
14. After the crosshead-balance nut has been tightened, tighten the rod packing
bolts evenly in 25% increments to the recommended torque in Table 1-12 on
page 1-16. This procedure will bring the pressure packing up square on its nose
gasket. Alignment is readily accomplished by the use of feelers to maintain a
uniform clearance all around between the case bore and the rod.
NOTE: THE FINAL TORQUE FOR THE ROD PACKING BOLTS SHOULD BE
REPEATED UNTIL NO TURNING OF THE FASTENERS IS OBSERVED. THE
TORQUE ON THESE FASTENERS SHOULD BE RE-CHECKED AT THE NEXT
SERVICE INTERVAL.
15. Retighten the small tie stud nuts. Re-install the tubing connections for the oil
supply, primary vent and/or coolant. Take care not to cross-thread the tubing
nuts. Tubing nuts must be tight. Refer to the Swaglock “Tube Fitting Instructions”
on the Ariel web site in Vendor Literature.
NOTE: AFTER INSTALLING THE NEW PRESSURE PACKING RINGS, REFER TO
“FORCE FEED LUBRICATION SYSTEM” ON PAGE 4-51 FOR INSTRUCTIONS
FOR PRIMING THE FORCE FEED LUBE SYSTEM. PRIMING SHOULD BE
REPEATED EACH TIME A COMPRESSOR IS STARTED BECAUSE OIL LINES
MAY HAVE BEEN BLED DURING DOWN TIME. FOLLOW INSTRUCTIONS IN
“FORCE FEED LUBRICATOR ADJUSTMENT” ON PAGE 3-12 FOR LUBRICA-
TION RATES THAT ARE RECOMMENDED FOR BREAK-IN OF A NEW
MACHINE. BREAK-IN LUBE RATES ARE TWICE THE NORMAL RATES - OR
ONE-HALF THE NORMAL INDICATOR PIN CYCLE TIME.
Types of Piston Rod Packing Rings
F
IGURE
5-23 T
YPE
“P”
P
RESSURE
B
REAKER
Letters toward pressure/cylinder
Type "P" Pressure Breaker
This is a single ring. It is cut radially into three equal seg-
ments. Total end clearance for the ring is 0.023 to 0.029
inches (0.6 to 0.7 mm) for PEEK rings and 0.011 to 0.017
inches (0.3 to 0.4 mm) for bronze and cast iron rings.
Maintain the end gap by adjusting ring gap or replacing the
ring. This ring breaks down or slows the gas flow without
sealing it completely.