2205Q2JE-HO-S6-N_2020.01.
Chapter 5 Maintenance and Inspection
SCV-series Screw Compressor 5.5 Reassembly
5-41
.
c) After installing the thrust bearing, attach the thrust washer [250], lock washer [40], and torsional slip
washer [237]. Then, tighten the lock nut [39] at the specified torque or within the specified range of
the tightening angle (refer to Chapter 7, Section 7.3 "Tightening Torques for Bolts and Nuts" in this
manual) to secure the inner race of the thrust bearing on the rotor shaft.
d)
After tightening the lock nut, turn the M rotor shaft by hand to make sure that rotation of rotors is
smooth.
Thrust Washer Lock Washer and Torsional Slip Washer
After titeging the Lock Nut Claw for rotation stop
Tightening the lock nut while keeping the setting position between the lock nut wrench hooks and
the lock nut notches may cause to make the rotor run-out to enlarge due to uneven tightening
forces. Change the setting position between the lock nut wrench hooks and lock nut notches about
four times when fastening the lock nut.
As clearance fit is used for the inner race of the thrust bearing, this tightening work is
very important because the bearing is secured only by the tightening force of the
lock nut.
When the thrust bearing has been replaced, the dimensional difference between the
sides of the inner race and outer race varies even if it is within the tolerance of the
applicable standard specification. As such, if the thickness of the thrust bearing
alignment spacer that has been used is insufficient, and if the lock nut is securely
tightened from the first, the end clearance between the rotor shaft end and the end
face of the discharge side bearing head will be lost. Furthermore, as the balls are
pressed against the rolling contact surface to create impression on the surface, it will
damage the bearing. To avoid this, gradually tighten the lock nut while rotating the
rotor to make sure the outer race is free, until the lock nut is fully tightened. If it
comes to require more force to turn the rotor while the lock nut is being tightened,
the thickness of the spacer is considered insufficient.
To Next Page
Loading...
Need help?
General
