Viking Pump TSM270: RL41507 Industrial Rotary Lobe - Manual (Page 8)

SECTION TSM 270 ISSUE F PAGE 8 OF 10
Caution: As the locknut is tightened, check to make sure
the lobes are still projecting beyond the face of the casing. If
they are not, rotate the bearing housing clockwise until they
are. Recheck to make sure the locknuts and end cap
capscrews are tight. If left loose, pump end clearance
will be lost and the pump may seize.
10.Set the end clearance. Refer to Thrust Bearing
Adjustment, page 8. Put the O-ring in place, then install
the gear case by visually centering the lipseal over the
shaft. Install the six capscrews, and torque evenly. Fill
with gear oil to the middle of the sight glass.
11.Place the O-ring and reinstall the head.
12.Tighten the 6 setscrews around each P/S®-II seal. Turn
the centering tabs 90°.
THRUST BEARING ADJUSTMENT
1.Remove the pump head if is not already off.
2.Remove (4) allen head pipe plugs in the side of the
bracket. Loosen the setscrews on the bearing housing.
3.Using the bearing housing spanner wrench, turn the
bearing housing counter clockwise (viewed from shaft
end), until the lobe is touching the bottom of the casing
bore.
4.Using a depth micrometer, measure the depth from the
front face of the casing to the face of the lobe; this is the
total end clearance.
5.Multiply total end clearance by .6. Turn the bearing
housing clockwise until the lobe is this distance from the
front face of the casing.
Caution: The end clearance must be set while turning the
bearing housing assembly clockwise. If set while turning
counter-clockwise, the lobes may float and cause damage
or galling.
6.Tighten the bearing housing setscrews on both sides of
the bracket to 100 in-lbs and install the 1/8” Allen head
pipe plugs.
7.Repeat this procedure for the other lobe.
Caution: Recheck to make sure the locknuts and end cap
capscrews are tight. If left loose, the end clearance may
be lost, resulting in pump seizure.
9.Rotate each bearing housing assembly clockwise until
the lobes project slightly beyond the face of the casing.
Place a wooden block or brass bar in between the lobes
to block rotation. Install lockwashers and locknuts and
tighten with the spanner wrench. Locknuts must be
tightened to 600 ft-lb torque. This torque is required
to obtain the proper bearing preload and ensure the
bearing/timing gear assembly is locked securely on
the shaft. This torque can be simulated by applying
approximately 600 pounds of weight with a one foot
wrench or 200 pounds of weight with a three foot
wrench. Adjust the bearing housing assembly to
position lobes flush.
DANGER !
Before opening any Viking pump liquid chamber
(pumping chamber, reservoir, etc.) be sure:
1. That any pressure in the chamber has been
completely vented through the suction or
discharge lines or other appropriate openings or
connections.
2. That the driving means (motor, turbine, engine, etc.)
has been “locked out” or made non-operational so
that it cannot be started while work is being done
on pump.
3. That you know what liquid the pump has been
handling and the precautions necessary to
safely handle the liquid. Obtain a material safety
data sheet (MSDS) for the liquid to be sure these
precautions are understood.
4. That the timing gearbox to cool before handling the
pump. The oil will become very hot during normal
operation. Allow the timing gearbox oil.
Failure to follow above listed precautionary
measures may result in serious injury or death.