Goulds Pumps 7200CB - IOM - Manual (Page 120)

Maintenance
i) Loosen the Group A nuts.
j) Repeat steps F through H for the Group A nuts.
k) Torque Group B nuts to value found in the table.
l)
Torque Group A nuts to value found in the table.
2. The rotating element must be centered inside the bundle.
a) Disassemble thrust bearing housing as necessary to remove bearing spacer (217). See
appropriate thrust bearing housing disassembly section.
b) Push the rotating element towards the coupling end until it stops.
c) Measure the distance from the thrust bearing shoulder on the shaft (122) to the bearing
housing saddle face on the head (184).
d) Pull the rotating element towards the thrust end until it stops.
e) Again, measure the distance from the thrust bearing shoulder on the shaft (122) to the
bearing housing saddle face on the head (184).
The difference between the two measurements is the total travel of the rotating
element.
f) Calculate the average of these dimensions.
g) For ball bearing pumps only, measure the shoulder depth on the inboard cover (119A)
and subtract the calculated average dimension.
For hydrodynamic pumps only, measure the thrust bearing shoulder depth on the thrust
bearing housing (134A) and the over all length of one of the tilt pad bearings including
the holder (280). Add these two dimensions and subtract the calculated average
dimension.
The result is the bearing spacer (217) thickness required to properly center the rotating
element.
h) Remachine the spacer as necessary making sure that both faces are parallel within
0.001 in (0.025 mm).
3. Reassemble thrust bearing housing as necessary. See appropriate thrust bearing housing
assembly section. For ball bearing pumps only, the only exception to this is the installation
of new thrust bearings. See step 4.
4. For ball bearing pumps only, assemble a new set of thrust bearings (112A) in a back to
back arrangement onto the shaft (122). The bearings are an interference fit.
a) Install bearing spacer (217) onto the shaft (122).
CAUTION:
Burn hazard. The bearings will get hot. Wear insulated gloves when handling the impeller.
b) Heat the bearings to 250°F (120°C) with an electronic induction heater.
The induction heater also demagnetizes the bearings.
NOTICE:
Do not use a torch and do not force.
c) Install the bearings (112A), the oil ring sleeve (443B), and the bearing locknut (138)
onto the shaft.
d) While the bearings are hot, tighten the locknut by hand with a spanner wrench until the
bearing is snug against the shoulder.
e) Allow the bearing assembly to cool slowly to room temperature.
Do not rapidly cool the bearings with compressed air or other means.
f) When the bearing assembly is fully cooled, remove the locknut (138), install the
lockwasher (382), and install the locknut.
118 Model 7200CB, API Type BB5 Barrel Multistage / ISO 13709 2nd Edition / API 610 11th Edition Installation, Operation, and
Maintenance Manual