Page 262 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

244 Major Process Equipment Maintenance and Repair

CW ROTATION

C’CW ROTATION

INCREASER

C’C
c. 0 ROTATI ON
W
D. @ CW ROTATION

Figure 6-22. Bearing loading directions for gear and plnion bearing, speed increasers and
reducers.

without disturbing the permanent mounting pad. The elevation of the
concrete foundation should allow for final grouting of the machinery
once accurate alignment of the shafts is complete. Most manufacturers
recommend that a minimum of 1/16 in. of shims be used between the gear
and soleplate to allow for final alignment.
The common baseplate or bedplate is a rigid structural steel foundation
common to both the gear unit and either the prime mover or the driven
equipment. This type of foundation is quite permanent. The gear manu-
facturer occasionally supplies the baseplate with the gear roughly aligned
to the prime mover or driven equipment. In this case, final alignment is
necessary after the baseplate has been grouted in.
Mountlng of Coupllngs

Before attempting to mount the coupling, inspect the coupling bore and
shaft diameter with a micrometer to determine that the coupling bore and
shaft are correct. Also, inspect the key and keyseat for proper fit, making
certain that the key sits at the bottom of the shaft keyway and that there is
clearance at the top of the key. If the keyway extends past the coupling