Thrust Balance Valve Removal
The Thrust Balance Valve (TBV) is replaced with an on-engine tube and an in-line plate orifice. Corresponding control system software modifications are made along with the hardware installation. The orifice plate is used to passively control pressure in the piston cavity to regulate the axial position of the low pressure rotor system and the loading of the No. 1 bearing, eliminating the potential for mechanical failures associated with the TBV.
Applicable Turbine Models
- Replacing the thrust balance valve with the new thrust balance orifice system eliminates the maintenance and oil leaks from the TBV.
- Reduces trips related to TBV software.
- New software is installed for monitoring thrust balance cavity pressure and annunciate an alarm, if required.
- Increase Uptime
- Improve Maintainability
How it Works
- The new thrust balance design eliminates the valve and its associated hardware.
- The TBV is replaced with an on-engine tube and an in-line plate orifice, which are installed with control system software modifications.
- The new thrust balance system uses an orifice plate as a passive control system to perform the piston cavity pressure regulation.
- The tubing is mounted directly on the turbine using three transducers on the turbine rear frame struts.
- For LM6000PC packages, at least a S4 fuel core is required. However, the S5 fuel core offers additional trip reduction logic that further improves the system.
- For LM6000PD packages, at least a S5 fuel core is required.
- For MarkTM VI controls, S5 core upgrade is not available on LM6000 PD units.