Removing and Installing Plain Bearing -MAN B&W NA 57 TC

Tools Required

1. Bracket
2. Threaded rod
3. Hexagonal nut
4. Open end wrench

Starting Position

Silencer if air intake casing, compressor casing and gas admission casing are removed. Impeller taken off and turbine rotor removed. End cover on turbine end taken off.

SEQUENCE OF OPERATION

Removing

1. Screw two threaded rod into plain bearing.
2. Slip bracket over threaded rods and secure with hexagonal nuts.
3. Extract plain bearing from bearing casing by tightening the nuts uniformly.

Note: If possible, the nuts should be tightened simultaneously. For assessment of wear and inspection of bearing.When replacing the plain bearing, also replacing cover as the effectiveness of a knife-edge-seal depends upon close radial clearance.

If the bearing cannot be extracted by means of the device, i.e if it has become a shrink-fit, it must be cautiously turned down after removal of the rotor. Should a lathe of corresponding size not be available, the bearing must be drilled and split up.

Installing

1. Install plain bearing on turbine end in bore hole of bearing casing in such a way that the straight pin of locating the bearing is pointing up.
2. Cautiuously press plain bearing into casing hole with the threated rods to guide it and making sure it is not cocked. The bearing flange must seat snugly against the bearing casing.
3. Unscrew both threaded rods.

Note: The oil catch groove of the plain bearing must be facing the turbine end. i.e it must be the outside and the straight pin pointing up. 

---