Regarding Lube oil pump

  • Thread starter rajkumarkrishna
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Both turbine and motor (i.e both are in the same compressor shaft) coupled with single compressor. Both turbine and motor are running at the same time. V have a lube oil system which supplying lube oil for turbine governor, T&T valve and compressor lubrication system. My main lube oil pump got fail while running and subsequently auxiliary lube oil pump came online. Still it can't build up the required pressure. Which resulted in Compressor motor trip. But my compressor was keep on running as the T&T valve was not shut. It resulted in compressor shaft damage.

So my question is how my T&T valve was not shut (lube oil is holding that spring loaded valve) when lube oil pressure had go down and my auxiliary pump didn't develop the required pressure? During this incident there is heavy rainfall that may result in low lube oil pressure. Can u able to identify the root cause of the problem? When lube oil pressure is really low it might have resulted in T&T valve shut down.

Have you consulted the L.O. P&ID to see if there are any orifices in the line to the T&T valve?

Perhaps the L.O. Bearing Header Pressure Regulator failed, causing the L.O. bearing header pressure and flow to be less than required, but the pump discharge pressure was okay.

What pressure was low? Pump discharge pressure? Bearing header pressure?

Most of the time the answers to these kinds of questions can be answered by consulting the P&IDs and checking each device and instrument along the way.

A control system includes the field devices and instruments in the various systems--L.O., Hydraulic, Seal Oil, etc. The solenoids and pressure regulators and control valves are all part of the control system--even if they're not connected (wired) to the control system.

If you can post the appropriate P&ID(s) to a web hosting service site and then post the link to the P&ID on, perhaps some kind soul will take a bit of time and analyze where the problem might be--but you're also going to need to tell us which pressure was low and how that was known to you. You just haven't provided enough information for us to be of much more help.

Than to remind you that most questions like this can be answered by consulting the P&IDs for the various systems and then working through the devices of each system until you locate the problem.

Hope this helps!