Viking Pump TSM142.2: LS-M 225/4225 - Manual (Page 12)

SECTION TSM 142.2 ISSUE E PAGE 12 OF 14
INSTallaTION OF CaRBON
gRaPHITE BUSHINgS
TOTal END ClEaRaNCE CHaRT
PUMP
SIzE
TURN OUTER END CaP
COUNTER-ClOCKWISE
NO. OF NOTCHES
TOTal
END
ClEaRaNCE*
LS 5 .010
Q, QS AND M 7.5 .015
THRUST BEaRINg aDJUSTMENT
* Total End Clearance includes extra clearance for
temperatures of 450°F (232°C).
FIgURE 11
See Figure 10, page 11.
1. Loosen the two setscrews over each of the outer and
inner end caps.
2. Turn the inner end cap clockwise (viewed from shaft
end) until it projects slightly into the opening on the side
of the bracket exposing approx. three threads.
3. Turn the outer end cap clockwise until the rotor is tight
against the head and the rotor shaft cannot be turned.
4. Make a reference mark on the bracket end, opposite
a notch on the outer end cap. Back off the outer end
cap the required number of notches as shown in the
Total End Clearance Chart, see Figure 11. Each notch
represents .002” end clearance.
5. High viscosity liquids require additional end clearances.
The amount of extra end clearance depends on
the viscosity of the liquid pumped. For specific
recommendations consult the factory.
6. Tighten the inner end cap with a spanner wrench. Tap
the spanner wrench lightly but DO NOT OVER TIgHTEN
as it will damage the threads.
7. Tighten the set screws that hold the inner and outer end
caps to prevent their turning in the bracket.
8. Check the rotor to determine if it turns freely; if it does
not, add more end clearance.
When installing a new carbon graphite idler or bracket
bushing, extreme care should be taken to prevent breaking,
as it is a brittle material and easily cracked. If cracked the
bushing will quickly disintegrate. NOTE: Using a lubricant
and adding a chamfer on the bushing and the mating part will
help in the installation of carbon graphite bushings.
An arbor press should always be used for installing carbon
graphite bushings. Be sure bushing is started straight and
DO NO STOP pressing operation until bushing is in proper
position. Starting and stopping will invariably result in a
cracked bushing.
Carbon graphite bushings with extra interference fits are
frequently furnished for high temperature operation. These
bushings must be installed by a shrink fit. Heat the bracket or
idler to 750ºF (400ºC) and install cool bushings with an arbor
press. (If facilities are not available for this temperature,
it is possible to install with 450ºF (232ºC) temperature.
However the lower the temperature the greater the possibility
of cracking the bushing.) Check for additional information
on high temperature applications see Engineering Service
Bulletin ESB-3.
Check bushing for cracks after installation. Coat surface of
the bushing with amyl acetate (banana oil). Let it evaporate,
and any cracks will be visible wet streaks. If cracks appear,
the bushing should be replaced. CaUTION: Amyl acetate is
a flammable solvent and should be used with care.