Page 381 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

360 Major Process Equipment Maintenance and Repair

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10. Inspect and lubricate the governor linkage. For specific details on
preparing the governor for startup, see Governor Operation in
Chapter 10.
11. Fabricate a clamp or other blocking device to secure the coupling
sleeve (if applicable) to the hub while operating the turbine uncou-
pled.
12. Check for free movement and clearance between auxiliary reset-
ting lever and cam mechanism.

lnltlel Startup, Noncondensing lWbines

1. Thoroughly drain the steam inlet piping, turbine steam chest and
casing, and the exhaust piping of any accumulated water.
2. Open the turbine exhaust valve. If overload hand valves (1, Figure 8-
6) are furnished, they must also be opened. Turn the governor speed
adjustment to minimum speed (Governor Operation, Chapter 10).
3. Latch the resetting lever (1 1, Figure 84) and slowly open the steam
shut-off valve until the turbine reaches approximately 500 r/min.
Immediately check the operation of the trip valve by striking the trip
lever (30, Figure 8-4). Close the steam shut-off valve as the turbine
speed decreases.
4. Latch the resetting lever and slowly open the steam shut-off valve to
bring the turbine back to 500 r/min. Remove the inspection plugs (28,
Figure 8-5) from the bearing caps and check to be sure the oil rings are
rotating. Monitor the speed carefully during the low speed operation.

Caution: Steam should not be admitted to the turbine casing by par-
tially opening the inlet steam shut-off valve while the ro-
tor is stationary. This umdition will cause uneven heating
of the turbine rotor and casing which may result in a dis-
torted casing, bowed rotor shaft or other related prob-
lems. Do not leave the turbine unattended at any time
during the initial startup.

5. Introduce cooling water to bearing housing cooling chambers to
prevent overheating. (See Table 8-5). Listen for any rubbing, un-
usual noises or other signs of distms in the turbine. Feel the bear-
ing housings and oil lines, to detect overheating or vibration. Do
not continue to operate if any of these conditions exist. Shut down
the turbine; locate and correct the cause of the problem. See the