Waukesha Bearings CQ Tilting Pad Thrust Bearings - Manual (Page 4)

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The alignment may be checked by gauging just below the casing joint and at the
bottom, measuring to points just inside the collar periphery (see Fig 2, Page 1).
An alternative method is to replace the thrust ring by a temporary dummy ring having
the same overall dimensions, the ring faces being accurately machined flat and parallel.
The collar face is then smeared lightly with blue marking and the shaft rotated, keeping
the collar face in contact with the dummy ring. A study of the marking of the ring will
indicate whether the casing is in correct alignment. By smearing marking on the
dummy ring, the collar can be checked for truth. It is not advisable to adopt this method
using the actual thrust ring, since the pads are held only loosely and may collect
marking on the faces when they are actually not in contact with the carrier ring, so
giving a false impression.
When checking alignment, the rotating parts should be completely assembled with all
masses in position as during operation. In some cases shafts are subjected to bending
when in operation and it may be necessary to allow for the bending deflection when
determining initial alignment, so that the bearings are correctly aligned when under full
operating conditions.
This static alignment check should result in a slope less than 0.0015 mm/mm, although
in practice slopes considerably less than this are achievable, and beneficial to bearing
operation, within the normal engineering standards associated with rotating industrial
machinery.
6.3.Assembling the Bearing in the Machine
The method to be adopted may depend upon the construction of the individual
machine, so the following remarks cover only the broad principles.
Before commencing final assembly, always see that the interior of the casing and all oil
passages and pipes are perfectly clean. Remove all loose dirt and wipe clean. If the
casing has been painted with protective coating, wash this off and wipe clean. A good
guide to the cleanliness is if a clean white cloth can be rubbed over the surfaces without
being soiled. Use clean cotton cloths for cleaning – do not use waste as particles which
are left behind can cause trouble.
See that the interior and shaft surfaces are freely coated with clean lubricating oil during
assembly.
In the case of one piece thrust rings, pass the ring over the free end of the shaft,
presenting the stop pin to its recess, until the ring sits snugly in position. Then fit the
collar, tighten up and lock securely.
In the case of thrust rings in halves, installation in its housing should commence as
follows:
The lower half ring (without a stop pin) should be inverted over the shaft with the pad
faces touching the collar face and wheeled into the lower half casing until the joint face
is horizontal.
The upper half ring (with a stop pin) should now be placed on the lower half ring
ensuring that both the pads and the equalising levers are correctly engaged in both
halves.