Page 395 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

Steam Turbines and Turboexpanders 373

Figure 8-9. Carbon ring assembly.

The joints between the bearing caps and bearing housings may be made
up with a thin coat of oil resistant sealant, such as “No. 2 Permatex,” if
desired.

Packing Case and Carbon Rlng Servlce

The steam end and exhaust end packing cases furnished on small tur-
bines (10, Figure 8-5), each house four carbon ring assemblies (Figure
8-9). Six carbon ring assemblies are housed in each packing case on
larger turbines (11, Figure 8-5). Each carbon ring assembly consists of
three carbon segments and an anti-rotation stop, which are held together
by a retainer spring. Axial positioning of the carbon rings is maintained
by machined grooves in the packing cases.

Packlng Case Disassembly, Small Turblnes

1. Remove cap screws (7 and 8, Figure 8-5) from the horizontal and ver-
tical flanges on the top half packing cases.
2. Break the horizontal and vertical joints by prying the top half pack-
ing cases away from the bottom halves.
3. Carefully remove the top half packing cases by lifting straight up
until they clear the carbon ring assemblies.