Axial Shift in a Steam Turbine 200 MW KWU Turbine

Perhaps this will help? inspect the thrust pad/bearing!

Balance piston:

The balance/dummy piston consists of a stationary and rotating part. The rotating part of the balance piston is included in the rotor and designed to reduce the axial forces of the blading to a low value. The remaining axial load will be carried on by the thrust bearing at any operation condition.

The stationary part is split horizontally and bolted together. It is supported in the cylinder in the same way as the blade carriers to allow for thermal expansion.

Gordon.

A 200 MW turbine generator is large enough that shaft thrust direction can be a function of allot of parameters. For example if you remove a high pressure heater from service it may reverse the thrust on the turbine rotor. This is not a concern as long as bearing metal temperatures for the thrust bearing are in normal parameters. High bearing metal temperatures is a cause for concern more so than the direction of the thrusting direction of the shaft. I have over 38 years of experience on large turbine generators and I would not worry about the direction of the thrust as long as the bearing is handling the metal temperatures but if the direction is abnormal condition for this particular machine it may indicate either improper operation of the machine or there is a steam path problem. In that case you need to do a thermo performance evaluation against the heat rate diagram of the manufacturer to diagnos the problem which may be imminent.