Page 295 - Sustainable On-Site CHP Systems Design, Construction, and Operations

268 Op erations

Daily Monthly Qtrly Semi- Annual Annual
Maintenance
Check the over-speed trip by accelerating the turbine to X
trip speed
Clean all linkage systems and inspect for wear X
Clean and oil or grease all the moving parts X
(fulcrum points)
Remove and inspect bearings X
Inspect radial contact surfaces (journal) X
Inspect axial contact surface (thrust faces) X
Make sure no signs of overheating, excessive wear, X
including dents, grooves, tears, or dirt
Check the effectiveness of all drains X
Disconnect and separate couplings. Remove all grease X
and sludge and then flush. Inspect wear on the hub
and cover teeth. Then dry and replenish with new, high-
quality grease
Check the sentinel and relief valves to ensure they are X
operational. The relief valve should start opening when
the sentinel valve opens and should completely open
when the pressure in the casing is 10% above normal
pressure
Operate turbine without a load and inspect governor X
operation and vibration
Drain governor’s oil, if applicable, while it is hot; flush X
governor and replace oil
Remove and clean governor valve and internal steam X
strainer. Check for leaks
Send oil sample out for analysis X
Replace oil filters
The turbine internals must be periodically inspected. 3 years
The frequency of inspection depends on steam
conditions and operation but should not exceed 3 years
TABLE 16-2 Typical STG Maintenance Schedule

both CHP and district heating and cooling plants such as feed pumps, deaerating (DA)
feed tanks, condensate pumps, condensers, and cooling towers. Cleaning and general
maintenance on these equipments is relatively standard and well understood, but is
quite important in maintaining the CHP plant at its highest operational efficiency.
Other auxiliary systems in CHP plants are specialized and require special training
to perform either scheduled or breakdown maintenance on those systems. One example