2201Q4JE-MY-C9-N_2018.01.
Chapter 5 Maintenance and Inspection
Compound 2-stage Screw Compressor 4032**C
5.4 Disassembly and Inspection
5-27
5.4.11 Thrust Bearing Block
5.4.11.1 Disassembly of the High-stage Thrust Bearing Block
For the high-stage thrust bearing, one of two
types of bearings, i.e. the ball bearing and the
tilting pad thrust bearing, is used according to
the working fluid, requirements of the use of
the package unit and the applicable standard.
This section describes the ball bearing
specifications.
The specifications of two type bearings are not
compatible due to the machining difference
of the bearing head.
In case of the tilting pad thrust bearing
specifications on the high-stage thrust bearing
block, refer to next Section "Disassembly of
the Low-stage Thrust Bearing Block".
Figure 5-13 High-stage Thrust Bearing Block
The high-stage thrust bearing block of 4032**C has no spacer for the thrust bearing outer race. While
the thrust bearing outer race spacer is used to support (i.e., ensure a sufficient support width for) the
outer race of the thrust bearing, 250 or higher models use no spacer for the thrust bearing outer race
because the case (bearing head) side has sufficient margin to the support it.
a) Remove the lock nut [39-2] that has been loosened. Then, remove the torsional slip washer [237-2],
lock washer [40-2], and thrust washer [250-2].
b) The clearance fit is applied to two gaps between the outer race of the thrust bearing and the
bearing head, between the inner race of the thrust bearing and the rotor shaft.
Prepare a 1 or 2 mm diameter aluminum wire, make the tip of the wire flat by hammering, and
slightly bend the tip to make a hook. Then, insert the tip of the wire between the outer race and the
ball retainer of the thrust bearing [38-2] to hook and pull out the bearing. In this way, the bearing
can be easily removed.
c) The whole thrust bearing will be removed helped by the surface tension of the oil on the side face.
If you have failed to remove the whole bearing at once, put the components in the order of the
removal.
d) Inside the thrust bearing is an alignment spacer [42-2] for the inner race on the rotor shaft side.
The M rotor side has a marking of "M", and the F rotor side has a marking of "F".
Neatly arrange the parts removed, i.e., the thrust
bearing gland, thrust washer, thrust bearing, and
thrust bearing alignment spacer, separately for
the M rotor and F rotor as shown in the right
picture.
You must be very careful because if an assembly
error is made to result in a wrong combination of
parts after failing to neatly arranging and
separating the parts, it can lead to performance
degradation and/or dragging accident due to
overheating caused by being too narrow
clearance, for example.
