Patent ID: 8650878

Claim:
A steam turbine system comprising: a high pressure (HP) turbine operatively coupled to an intermediate pressure (IP) turbine and a low pressure (LP) turbine; a steam seal header for maintaining a constant self-sustaining sealing pressure to the LP turbine using a first steam flow in a seal steam line from a seal packing of the HP turbine; a leak off line coupling a leak packing of the HP turbine to the IP turbine; a connector line directly coupling the leak off line to the seal steam line upstream of the IP turbine; a valve coupled to the connector line for controlling the first steam flow to the steam seal header; and a controller for controlling operation of the valve, wherein the valve delivers more steam flow to the seal steam line during a lower load condition of the IP turbine than during a higher load condition of the IP turbine such that the steam seal header uses greater than or approximately 90% of the first steam flow to maintain a sealing pressure to the LP turbine, and the steam seal header leaves approximately 10% or less of the first steam flow unused during all load conditions of the turbine system.