GE MS6001B, Maintenance Instructions Manual

Page: 131 / 370

Inspection and Maintenance Inspection and Maintenance Procedures
IMP–25
The inlet ductwork and silencer should be inspected at least once a year for leakage or any entrapped
material. Leaks can be sealed with an appropriate caulking compound. Entrapped material should be
removed to prevent possible foreign object damage. Any rust or oxidation spots on other than Cor-Ten
material should be scraped and repainted.
Inlet Guide Vanes
Inspect the inlet guide vanes for corrosion pitting. Pay special attention to the fillet area of the inlet guide
vane. If pitting is seen in this area, it may be assumed that there is also pitting on the underside of the
vane/platform junction. Liquid penetrant inspection should be made in the fillet area. Report findings
on PGS/GT-FF-6108 Inspection Report.
Moisture Separators (if applicable)
On units equipped with moisture separators, the separators will typically be located between the inertial
separators and the high efficiency media filters.
Evaporative Coolers
Evaporative cooler pump controls should be manually activated when the ambient dry bulb temperature
is above 60
°
F (16
°
C) and approximately one-half hour prior to gas turbine start-up. After the generator
breakers close, the controls should be switched to “automatic.” This procedure will wet the entire bank
of media prior to the airflow, thus precluding entrainment of liquid water into the air from the dry media.
Note: At the end of the cooling season clean out tanks and wash media with
water.
Water Flow Adjustment
Open the valves controlling the water flow to the header approximately 3 turns from fully closed. With
the turbine operating, check the media in the cooler. If the media is not fully wet (typically at the opposite
end from the pump), open the valve by one-half turn increments until the media becomes fully wetted.
Allow five minutes between valve adjustments for wetting to occur. Once the valves have been set, no
further adjustments are necessary other then periodic checking of the media wetness during the day’s
operation. In some coolers, the water distribution system may not allow water to reach the final 12 in.
(30.5 cm) of the media away from the pumps under any condition; this is normal and causes no perform-
ance loss.
Note: Supplying an excessive amount of water to the header may cause liq-
uid water carry-over into the airstream. Allow only enough water to
maintain media saturation.
Shut Down Pump Operation
Approximately one-half hour prior to shut down of the gas turbine, switch the pump controls off. This
will allow the media to thoroughly dry out, precluding possible condensation in the inlet ductwork when
the turbine is not operating.