2201Q4JE-MY-C9-N_2018.01.
Chapter 5 Maintenance and Inspection
Compound 2-stage Screw Compressor
4032**C
5.5 Reassembly
5-37
5.5.3 Bearing Head and Rotor Casing
Since the bearing head gasket [12] is not symmetrically shaped, carefully check the
orientation when installing the gasket.
If you place the bearing head gasket by just hanging it on the stud bolts, the gasket
will protrude into the inside of the rotor casing when the casing is assembled. Apply
sufficient amount of oil, etc. to the gasket to make it fully attached to the surface to
prevent protruding upon the assembly.
a) After fitting the unloader push rod [67-1] into the hole of the bearing head [11-1], slide either the
bearing head or the rotor casing [1] to join them together.
b) As the full height of the high-stage main rotor casing [1-2] is lower than that of the bearing head,
both centers will not be aligned when they are placed on the work bench. Therefore, either use a
pedestal as used in the disassembly process or lift the main rotor casing using a crane or other
device to align the centers.
c) After lightly fastening two bolts, drive in the alignment
pins [3] to fix the position by using a copper or an
aluminum hammer.
Note that a low-stage hexagon socket head cap screw
[2-1] is a washer faced bolt.
d) After tightening the bolts [2], check that the bearing
head gasket is not protruding into the inside of the main
rotor casing.
e) Also, move the slide valve back and forth to check that
it works normally.
f) The bottom bolts that cannot be fastened on the work
bench are to be fastened later on.
Be sure to check for possible protrusion of the gasket after the bearing head and
rotor casing have been assembled together. If you forget to check it out, it may lead
to a measurement error in the end clearance adjustment process, as the gasket may
be placed in between the rotor end and the bearing head surface. Furthermore, if the
compressor is operated after the end clearance is erroneously adjusted and fixed in
this condition, it may compromise the performance.
