3.4.1 Shaft Alignment
Many users now require a 0.002" T.I.R. alignment to gain a greater mean time between failure
(MTBF). All 3996’s that have been shipped after 1/9/90 have been aligned at the factory to .002"
T.I.R.
Assembly procedures have been developed to align the pump shaft and the driver shaft to .002"
T.I.R. Each pump is assembled using a torque range of +10% of the recommended torque value of
the bolts. If .002" T.I.R. alignment is required by the customer, a final alignment
must be done in the field.
The following is the procedure that has been developed for the use in the field and on our assembly
floor to obtain 0.002" shaft to shaft alignment.
3.5 3996 Shaft Alignment Procedure
1.
Inspect all machined fits for signs of contamination or damage. All fits must be clean. If the
pump is new this step is not necessary.
2.
Loosen all motor, motorsupport, and casing bolts, but do not remove.
HINWEIS:
Make sure jack bolts on the casing are backed off.
3.
Move shaft assembly (shaft, housing, and impeller) away from casing angle face, by adjusting
the bearing housing. A 1/4 turn of bearing housing jack bolts is sufficient to ensure the impeller
does not ride on the casing angle face. Proper indication cannot be done with the impeller tou-
ching the angle face.
4.
Tighten motor hold down bolts in a criss cross pattern to the recommended torque. (Refer to the
Fastener Size and Recommended Torque Values)
5.
Tighten the motor support bolts in a criss cross pattern to 90% of the recommended torque va-
lue of the bolts. For example, if the recommended torque value for the bolts is 60 ft.-lbs., tighten
bolts to 54 ft.-lbs.
6.
Tighten casing bolts in a criss cross pattern to 90% of the recommended torque value.
7.
Attach a dial indicator to the driver shaft and mark the pump shaft so the indicator always con-
tacts the same location on the pump shaft.
8.
Rotate both shafts in the same direction and record the indicator readings every 90 degrees (4
places).
9.
Incrementally increase the torque value and begin to tighten the necessary bolts to bring the
shafts into alignment. Do no exceed 110% of the recommended torque values. After each series
of tightening, repeat Step #5 until the desired alignment is achieved.
HINWEIS:
Indicate off the hub to the motor lock I.D., in the motor support, when supplying the pump
less motor.
10. Reset the clearance between the impeller and casing angle face to .008 (.015 if using the high
temperature option). Ensure the bearing housing jack bolts are secured.
HINWEIS:
Tighten coupling bolts and hub set screw onto shaft. Torquing of these components is not
done at the factory, yet is required at the site. Please reference the coupling manufacturers
instructions for correct torque levels.
3.5 3996 Shaft Alignment Procedure
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3996 Installation, Operation and Maintenance Instructions
