Tuthill M-D Pneumatics 9000 Series, Operator'S Manual

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5.5 MOTOR DRIVES
Two drive connections commonly used are direct drive and V-belt drive.
5.5.1 DIRECT COUPLED
When installing the motor directly to the booster, align shafts to coupling in accordance with the coupling
manufacturer’s instructions. Boosters shipped with motor directly coupled and mounted on a common base
have been aligned prior to shipment and normally no further alignment is necessary. However, alignment
should be checked and adjustments made if necessary prior to starting the unit.
Coupling halves must correctly fit the booster and drive shafts so that only light tapping is required to install
each half. The two shafts must be accurately aligned, A direct coupled booster and motor must be aligned
with the two shafts not having more than .005” (.13 mm) T.I.R. (Total Indicator Reading). Face must be
aligned within .002” (.05 mm) .
Proper gap between coupling halves must be established according to coupling manufacturers instructions
with the motor armature. This will minimize the change for end thrust on the booster shaft. All direct coupled
base mounted units must be re-aligned and greased after field installation.
5.5.2 V-BELTS
If the motor and booster are V-belt connected, the sheaves on both motor and booster shafts, should be as
close to the shaft bearings as possible. Booster Sheave is not more than 1/4” (6.5 mm) from the booster
drive end cover. The drive sheave is as close to the driver bearing as possible. Care should be taken when
installing sheaves on the booster and motor shafts. The face of the should be accurately in line to minimize
belt wear.
Adjust the belt tension to the to the manufactures specifications using a belt tension tester. New belts should
be checked for proper tension after 24 hours of run time. When manufacturer data is not available industry
guidelines are 1/64 inch deflection for each inch of span at 8 to 10 pounds of force in the center of the belt.
Insufficient tensioning is often indicated by slipping (squealing) at start up. Belt dressing should not be
used on V-belts. Sheaves and V-belts should remain free of oil and grease. Tension should be removed
from belts if the drive is to be inactive for an extended period of time. For more specific information consult
the drive manufacturer. In a v-belt drive, the booster sheave must fit its shaft accurately, run true, and be
mounted as close to the bearing housing as possible to minimize bearing loads.
A tight or driving fit will force the drive shaft out of its normal position and cause internal damage. A loose
fit will result in shaft damage or breaking. The motor sheave must also fit correctly and be properly aligned
with the booster sheave.
Adjust motor position on its sliding base so that belt tension is in accordance with drive manufacturer’s
instructions. Avoid excessive belt tension at all times. Recheck tension after the first ten hours of operation
and periodically thereafter to avoid slippage and loss of booster speed.
Check booster after installation and before applying power by rotating the drive shaft by hand. If it does
not rotate freely, look for uneven mounting, piping strain, excessive belt tension, or coupling misalignment.
Check booster at this time to insure oil was added to the reservoirs.