Turbo Mechanics

To balance out axial forces...

"... each stage of the turbine will produce an axial force in the direction of flow of steam proportional to the steam flow passing through that stage. The resultant axial force from all stages is balanced out approximately by a balance wheel located at the high pressure side of the rotor, whose job is to create a similar force to that created by the steam on the blading but in the opposite direction. The axial bearing will then have to cater only for the resultant force ..."

You may want to look at this previous thread

http://cr4.globalspec.com/thread/67110/Axial-Shift-Related-Problem-in-250MW-Steam-Turbine

There may even be some other earlier threads to review.