RETROFITING STEAM TURBINE GOVERNING
As part of a big petrochemical revamping project we retrofitted control system of steam turbines from Ellliot-Ebara at heart of a process plant.
Additional to high cost of maintenance and insufficient operation, the old hydraulic governor system of steam turbine was raising problems during operation and caused many unexpected plant shutdown. The governing control system was an open loop hydraulic control without any feedback from actual speed and many external factors could cause unsteady turbine operation.
We Designed, built and installed a new control system from Siemens S7-400 for the turbine and added new speed sensors to get feedback from actual speed.
Replacing old hydraulic governing system by new servo motor with LVDT from VOITH was main part of this project.
Our main challenge was extra high temperature of ambient in location where servo supposed to be installed, it was close to body of steam turbine then by an innovative solution we disassemble original VOITH servo and made it apart and installed three way valve 7 feet far from the turbine.
We planned for installation and commissioning of each individual loop to have short plant down.
By completing this project, the customer could use advantage of new turbine control system and plant production throughput 
improved and cost of maintenance and production deducted.