Table of Contents
Advertisement
of the sheave on the motor shaft to get proper alignment. Once proper alignment has been obtained, lock
the sheave in place on the motor shaft; then the jack bolt lock nuts must be tightened. One set of nuts is
tightened down against the base to lock the jack bolts in place. The second set is locked down to
sandwich the hinged plate against the jack bolt heads. When lock nuts are in place, a final alignment
check should be made with the straight edge.
Note: Any of the following actions will require the sheave alignment be checked and any or all of the
above steps repeated. (Initial start up at customer site, compressor change, motor change, unit
relocation, or when the belts are replaced.)
It's important to note that the belts should not be over tightened. To check belt tension use a Gardner
Denver Belt Tension Gauge, Part Number 00543217. V-belt tension will drop after the first 8-24 hrs of
unit run time. Failure to check and re-tension the belts after the initial run-in period will result in belt
slippage and premature belt failure. Please see Figure 7-1, page 66, for proper belt tension.
Interference between the fan and the orifice can damage equipment. Be certain
the orifice has even clearance around the fan before starting the unit.
REPLACING THE COMPRESSOR SHEAVE
1.
Disconnect, lockout and tagout the power supply to the starter.
2.
Remove the guards.
3.
Using the adjusting screws, jack the motor base up to loosen the belt tension, Remove the belts.
4.
Remove bolts from tapered bushing.
5.
Pull the sheave off the rotor shaft with a gear puller, if necessary.
6.
Install new sheave and tapered bushing.
7.
Install new belts. Check for correct belt tension and reattach the wire guard.
8.
Align sheaves with a straight edge. (See "SHEAVE ALIGNMENT", page 64).
9.
Assemble the guards.
CHECKING BELT TENSION - Using a spring scale, apply a perpendicular force to each belt at the
midpoint of the span and measure the deflection. Correct deflection force and deflection are shown in
Figure 7-1. To tighten belts, merely increase the center distance.
When a new set of belts is installed on a drive, the initial deflection force should
be 1/3 greater than shown in Figure 7-1. Recheck tension frequently during the
first 24 hours of operation
NOTICE
13-20-600
Page 65
Hide quick links:
Advertisement
Table of Contents
