GE Frame 9E Lube oil tank level indicator.


Thread Starter


What is considered as the normal level on the sight glass of the lube oil tank of the GE Frame 9E Gas turbine - when the unit is shutdown and off turning gear, also when running.
You should refer to the L.O. P&ID (Piping Schematic) for L.O. levels.

Certainly, when the unit is running the level in the L.O. tank will be slightly lower than when the unit is at rest (off cooldown). But, the difference should be only 25-50 mm (1-2 inches).

Units used to have a level indicator, with integral switches to indicate Low- and High L.O. levels (alarms). There was a "Normal" level indicator, and that should be related to the sight glass (which was a relatively recent addition to GE machines).

If I recall correctly, the midpoint of the sight glass was considered the "normal" level, and, again, the level will vary slightly with operation/non-operation.

Process Value

Lube oil tank level

if you have the PID of the lube oil scheme, you will see in the first page of it a representation of the tank with dotted lines representing different levels. Actually these are relative levels. please have a look at the thread below, i have explained how the levels are calculated.

during normal operation condition, ie with the MOP running the level needs to be maintained between the empty and the full mark. if you go below the low level alarm then there is a possibility of LO tank level going below the AOP suction face. If you load it High level alarm then if the machine trips or is shutdown and the AOP/MOP stops then the LO tank will near a over flow mark. so during operating condition maintain the level between the empty and full mark on the dial gauge you will do fine.

one another thing is the vacuum in the tank will also affect the level measurement. the normal vacuum is -(100-150) mmwc. you should also maintain the vacuum in this given range.