Heavy Duty Balanced Opposed Compressors - Ariel Corporation

Section 4 Part Replacement For Models: JGH:E:K:T
damage to the scraping edges. If packing case is “water”-cooled, see “Water-Cooled Piston Rod
Packing” on page 4-23.
6. Lay out parts on a work bench for progressive installation, with each part in its correct position
and the rod rings with their proper faces toward the pressure. Three long tie studs hold the pressure
packing together. The stud holes are unequally spaced to prevent misalignment of the stack
of parts. Note that all rod ring segments are carefully lettered; assemble them accordingly. This is
most important for proper sealing. Center side-loaded WAT and AL rings prior to tightening tie
stud nuts. Install tie nuts and tighten to the values in Table A-3 in Appendix A. Manually verify all
rings move freely, radially, in their grooves. Side-loaded rings are snug, but should still move
manually. Center these rings.
7. For new installations, carefully clean all accumulated dirt in the lines and compressor. Any foreign
material lodges in the packing and becomes destructively abrasive.
8. Prior to packing case installation, inspect end cup gasket for nicks and damage that may cause
leakage. If in doubt, replace the gasket. Verify the gasket surface in the packing counter bore on
the crank end of the cylinder/head is clean and not scratched.
9. Reinstall complete packing case assembly with oil supply point on top. Use rod packing bolts to
pull packing into place.
10. Reinstall packing diaphragm (if applicable) and wiper packing.
11. Reinstall piston and rod. See “Piston and Rod Installation” on page 4-14.
12. After tightening the crosshead nut, tighten rod packing bolts evenly to the recommended torque
in Table A-3 in Appendix A. This procedure squares the pressure packing on its nose gasket. To
align the packing, use feelers to maintain a uniform clearance all around between the case bore
and the rod. Rod packing bolt tightening on high pressure cylinders requires a torque multiplier.
NOTE: Repeat final torque for rod packing bolts until the bolts no longer turn. Re-check
torque on these fasteners at the next service interval.
13. Retighten tie stud nuts. Reinstall tubing connections and instruments (if applicable). Take care
not to cross-thread tubing nuts. Tubing nuts must be tight.
NOTE: After pressure packing installation, see “Force Feed Lubricator” on page 3-15 to prime
the force feed lube system and obtain recommended lubrication rates for new machine breakin.
Repeat priming each time a compressor is started because oil lines may bleed during
down time. Break-in lube rates are approximately twice the normal rates, or half the normal
indicator pin cycle time.
Long Two-Compartment Intermediate Packing
Compressors supplied with long two-compartment distance pieces include an intermediate packing
assembly that seals around the rod between the outboard and inboard distance pieces. This packing
assembly includes a single AL ring set.
For lubricated service, the force feed lube oils the top of the ring set at a very low rate because this
ring set is not subject to cylinder pressures and temperatures. The end-to-end seal in the cup and
the low lube rate of AL ring sets, ensures newly installed rings run virtually dry for the first few hours
of operation. To avoid damage to the rings and rod, copiously oil the ring set during installation,
before rod installation. Use only the same lubricant in the force feed lube system. If non-lube, see
“Component Cleaning and Thread Lube for Non-Lube Compressor Cylinders” on page 4-43.
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