SELWOOD SELTORQUE S150, Manual

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Selwood Seltorque S150 Manual
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The rubber element itself is free to slide on the
horizontal pins. It is therefore unnecessary to remove
the cap screws that secure the pins unless the pins
themselves have become damaged.
1.5.1 Preparation of the Centaflex Coupling
for Pump Removal
NOTE: Before commencing, mark the position of the
coupling assembly on the pump drive shaft. Pay
particular attention to the size of the gap between the
back of the rubber element and the face of the steel
adaptor plate. This gap has been factory set and is
maintained when the setscrew in the steel hub is
locked in position.
1. In order to allow the pump drive shaft to be
withdrawn from the steel hub of the coupling, it will
be necessary to loosen the setscrew located in the
outside radius of the steel hub just in front of the
rubber element. The setscrew clamps the
coupling assembly onto the top of the pump drive
shaft key and it is not necessary to completely
remove this screw.
2. Once the setscrew is loose the pump drive shaft is
free to be withdrawn from the hub of the coupling.
Note too that when the setscrew is loose the
coupling assembly is free to slide in either
direction onto the pump drive shaft or onto the
horizontal pins.
1.5.2 Centaflex Coupling Assembly
Sequence
1. The radial and axial screws connecting the rubber
element to the hubs must all be tightened to the
torque given in the table below, using a torque
wrench.
Tightening Torque
Centaflex
Size
Screw
Size
Nm mKp
16/22 M12 85 8,5
25/28 M14 140 14
30 M16 220 22
2. Tightening with a torque wrench is particularly
important. Tightening by feel will not do as
experience has proved the tightening torques in
such cases are far too low. Tightening torques
which are too low will inevitably lead to slackening
of the screws in service and consequently to the
destruction of the coupling.
3. Ensure that on tightening the screws, the
aluminium bushes in the rubber part are not
twisted at the same time, but sit straight. In order
to reduce friction between the screw head and the
aluminium part, a small amount of grease should
be applied under the head of the screw before
fitting.
4. If necessary, use a suitable tool for applying
counter pressure on the element to prevent
twisting of the rubber part during tightening of the
screws. This is particularly important with radial
screws, otherwise the cylindrical faces between
the aluminium insert and the hub will not engage
on the full area, but only on two corners. This will
inevitably lead to slackening of the screws and
subsequent destruction of the coupling. If the
coupling is supplied in a pre-assembled state do
not dismantle it, but fit it in this condition.
1.5.3 Replacement of the Steel Hub and
Rubber Element
NOTE: Once the Centaflex coupling has been
prepared in accordance with Section 1.5.1 above, it is
free to be removed from the horizontal pins on the face
of the adaptor plate.
1. If it becomes necessary to replace either the steel
hub or rubber element, the three radial caps
screws must be removed in order to separate the
two components. When removing these cap
screws it is recommended that the coupling
assembly remain on the horizontal pins for ease of
their removal.
Once the three radial screws are removed, the steel
hub can be separated from the rubber element.
Also at this stage the rubber element can be
removed from the horizontal pins of the adaptor
plate.
3. Replace the rubber element and/or steel hub as
necessary to refurbish the assembly.
4. Fit the rubber element onto the horizontal pins of
the adaptor plate.
5. Insert the steel hub into the centre of the rubber
element and align the radial mounting holes with
tapped holes in the hub.