2201Q4JE-MY-C9-N_2018.01.
Chapter 5 Maintenance and Inspection
Compound 2-stage Screw Compressor 4032**C
5.3 Compressor Disassembly Preparation
5-11
5.3.4
Removal of Connections to the Package Unit
If high-pressure refrigerant gas or refrigerant-mixed lubricating oil remains inside the
compressor, a gas and oil under pressure will gush out as soon as a sealed part is
opened and cause injury to the operator such as frostbite or loss of eyesight. Be sure
the check that there is no residual pressure before disconnecting any pipe joint.
When removing the compressor from the mounting base frame, the following parts must be
disconnected beforehand:
(1) Coupling to connect the compressor to the driving machine;
(2) Suction and discharge pipes of the compressor.
If the suction strainer is directly connected to the compressor, also remove the strainer;
(3) Oil supply lines to the compressor (Five lubricating oil inlet ports of low-stage, two lubricating oil inlet
ports of high-stage, one oil injection inlet port, and two ports for each of the capacity increase and
decrease controls);
(4) Electric wiring for capacity control operation (In some cases, the unloader indicator assembly may
be removed without removing the wiring. Refer to Section 5.4.1.1 in this chapter.);
(5) Compressor mounting bolts (foot bolts); and
(6) Intermediate connecting line from the low-stage discharge to high-stage suction of the compressor
(In some cases, this line is not removed, and the compressor is removed with this line attached.)
When removing oil lines from the compressor, there is possibility of gas and oil blowing out caused by
residual gas pressure. And any residual oil in the pipe will flow out. To be prepared for this, either check
the amount of oil outflow by slightly loosening the pipe joint or drain the oil from the oil temperature gauge
at the supply header before removing the pipe.
Work carefully in particular when disassembling the unloader cylinder block since there is residual
pressure and oil fills in the unloader cylinder. Moreover, prepare a larger volume container than the
unloader cylinder volume to receive oil flowing out.
For easy reconnection, disconnected electric wires should be properly marked for identification. Any
wrong reconnection may result in a startup failure or inability to operate the capacity control mechanism.
