Heavy Duty Balanced Opposed Compressors

FOR MODELS: JG AND JGA SECTION 5 - MAINTENANCE
Water-Cooled Compressor Rod Packing
When any disassembly of water-cooled rod packing cases is required, proper re-assembly
and testing is required. This is to ensure that the cases do not leak.
Re-assembly
Cases are lapped, and care must be taken to prevent scratching of the mating surfaces of
the cups. Scratches can cause significant leakage problems.
The cups are numbered on the outside diameter and are to be assembled in consecutive
order, starting with the end cup. The studs are offset so the cups will only fit one way.
Make sure the tie studs are completely screwed into the end cup. Put the proper ring in the
groove and facing the proper direction. Be careful when sliding parts onto the tie studs to
ensure that no scratching occurs to the lapped faces.
Install second cup next, put the rings into place, and make sure the two (2) small O-rings are
in place around the coolant holes.
Continue assembling the remaining parts in the proper configuration to the packing case
drawing. In consecutive order, by repeating the above step.
Install tie stud-nuts and tighten to the values given in Table 1-15 on page 1-15. Using fingers,
make sure that all rings move freely, radially, in their grooves. Side loaded AL rings will
be snug, but should still move using fingers.
Testing
100% verification of function is required for all internal passages.
The passages are to be checked by blowing compressed air thru the connection taps on the
flange and verifying that air is exiting at the proper holes. When air is applied to the connection
tap stamped “Coolant In”, air should be exiting the connection tap stamped “Coolant
Out”, or if air is applied to the tap stamped “Lube”, air should be exiting at the appropriate
cup on the inside diameter of the case.
Pressure leak test packing cases as follows:
1 Plug the “Coolant Out” connection>
2 Apply 60 to 100 psi (400 to 700 kPa) dry, compressed air pressure to the “Coolant
In” connection. For water cooled rod packing cases in non-lube service,
compressed air is to be oil free. Air should exit at connection tap “Coolant Out”.
Air applied to the tap stamped “Lube” should exit at the appropriate cup on the
inside diameter of the case.
3 Plug the “Coolant Out” connection and apply 60 to 100 psi (400 to 700 kPa) dry,
compressed air pressure to the “Coolant In” connection through a ball valve with
a calibrated pressure gauge located between the ball valve and packing case.
Close the ball valve and disconnect the air supply. There should be no pressure
drop for 5 minutes minimum.
4 If water cooled packing cases are used in lubricated applications, leak testing
may be done by submersing the packing case in oil with 10 to 100 psig (400 to
700 kPa) test air pressure. After the air trapped in the ring grooves has been
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