Turbine Package Operators Manual
Chapter 1
Turbine Package System Overview
1-11
Lubricating Oil System
Mineral lubricating oil is used to lubricate and cool the turbine journal and thrust bearings, the
generator bearings and the gearbox bearings, gears and splines. The oil is also used as a
hydraulic oil to operate the hydraulic starting system when starting the turbine.
General Description
The oil is delivered from an on-skid lubricating oil tank and circulated throughout the lubricating
system under normal running conditions by a main oil pump. The system includes a temperature
control valve, pressure control valve, filter, instrumentation and associated piping to provide the
correct delivery conditions.
The used oil is returned to the tank by gravity drainage to create a continuously circulating
system.
Heat is removed from the oil by an oil cooler circuit, which is controlled by the temperature
control valve.
A lubricating oil tank breather system is provided to vent to atmosphere oil fumes that are
generated whilst the turbine is running.
A schematic diagram of the lubricating oil system is located in this Manual Volume.
Lubricating Oil Tank
The lubricating oil tank is integrated into the underbase fabrication and is provided with internal
baffles to aid circulation and maximize removal of entrapped air. Covers are provided to facilitate
cleaning of the interior if contamination occurs.
The tank is fitted with immersion heater(s) to maintain the correct pre-start oil temperature.
Integral thermal protection is provided.
Flip lid filler point(s) with integral strainers are provided for filling and replenishment.
Level gauge(s) provide visual indication of the oil level within the oil tank.
Lubricating Oil Pumps
Three lubricating oil pumps are provided:
•
The main pump (XP1) which is mounted on, and driven by the auxiliary gearbox,
provides lubrication during normal running.
•
The auxiliary pump (XP2), which is submerged in the lubricating oil tank and driven by an
AC motor, provides lubrication during turbine start, run up and post shutdown.
•
The emergency pump (XP3) which is submerged in the lubricating oil tank and driven by
a DC motor, provides essential lubrication to the turbine hot bearing in the event of the
auxiliary pump or AC power failure, during or after shutdown.
Circulation between the three pumps is controlled by non-return valves, located in each pump
delivery system.
Each pump is provided with a pressure relief valve to guard against over-pressurization.
A strainer is provided at each pump suction inlet.
