Flowserve MARK 3 GROUP 4 - Manual (Page 40)

MARK 3 GROUP 4 USER INSTRUCTIONS ENGLISH 71569286 08-12
Page 40 of 48 flowserve.com
®
b) Set the impeller clearance by loosening the set
screws [6577] and rotating the thrust bearing
housing [3240] to obtain the clearance. Turn the
thrust bearing housing counter-clockwise until
the impeller comes into light rubbing contact with
the casing [1112]. Rotating the shaft at the same
time will accurately determine this zero setting.
Now, rotate the thrust bearing housing clockwise
to get the proper clearance. Rotating the thrust
bearing housing the width of one of the indicator
patterns cast into the thrust bearing housing
moves the impeller axially 0.1 mm (0.004 in).
(Figure 2).
It is recommended that two
people install an impeller. The weight of an impeller
greatly increases the chance of thread damage and
subsequent lock-up concerns.
c) Determine how far to rotate the thrust bearing
housing by dividing the desired impeller
clearance by 0.10 (one indicator pattern).
Tightening the set screws [6577] will cause the
impeller to move 0.005 mm (0.002 in) closer to
the casing because of the internal looseness in
the thrust bearing housing threads. This must be
considered when setting the impeller clearance.
Rotate the thrust bearing housing clockwise the
required amount to get the desired clearance to
the casing. Lastly, tighten the set screws [6577]
to lock the thrust bearing housing in place.