Gardner Denver VST110 Operating And Service Manual page 63

Interference-fitted Coupling Hub Installation and Removal – In the event that a coupling hub has to
be removed, please note that these are designed to fit on compressor and motor shafts with a transitional
interference fit. Coupling hubs and their companion shafts which have bore diameter which fall in the
interference range of the design fit, must be installed or removed with the air of a pulling tool and/or heat
dilation. The recommended steps are based on the assumption that the main motor has been pulled
away from the compressor and that the motor adaptor housing is still attached to the compressor.
Coupling Hub Installation:
·
Have coupling installation tool kit part number 302SBV074 available – contact GD for
sourcing details.
·
Assemble tool kit components unto coupling hub as shown on Figure 8-4, page 64.
·
Make sure that the keyway on the coupling hub and its companion shaft are properly de-
burred and clean and that the key fits easily into either.
·
Thoroughly cleanse the surface of the companion shaft and cover it with a thin film of anti-
seize lubricant part number 25BC850 – contact GD for sourcing details.
·
Expose complete assembly to heat source until the coupling hub reached a temperature of
200° F. Note that an oven is a preferred method to heat up the hardware.
·
With the help of heat insulating gloves, remove the coupling hub and tool kit assembly from
the heat source and quickly bring it to the companion shaft. Engage the coupling hub bore
unto the companion shaft and slide until the latter contacts the stop – item #1 on Figure 8-4,
page 64.
·
Once the coupling hub has cooled down sufficiently to grip the companion shaft, remove the
installation tool kit.
Coupling Hub Removal:
·
Have removal tool part number 90500151 available – contact GD for sourcing details.
·
Before removing an interference fitted hub, note and record the position of the hub with
relation to the end of the companion shaft. The hub must be re-installed at same relative
position, in order to provide the proper clearance for the coupling.
·
Assemble removal tool unto coupling hub as shown in Figure 8-5, page 64. Make sure that
the shaft protector piece is captured between the puller screw and the end of the shaft.
·
Apply torque to the puller screw with a suitable torque wrench to pull coupling hub away from
the shaft.
·
If torque applied to puller screw exceeds 130ft-lb, it indicates that a heavy interference fit
between the coupling hub and the companion shaft is present and that heat dilation must be
used to expand the coupling hub and loosen its grip on the shaft surface. Secure a suitable
heating source and apply heat to the coupling hub body while slowly rotating the companion
shaft assembly by means of the removal tool handle. Once the coupling hub metal has
expanded enough, the present tension of the removal tool will pull the coupling hub away
from the shaft.
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