Patent ID: 9540942
Date: 2017-01-10
CPC Classifications: F01D,F05D

Claim:
1. In a turbine system including a first turbine section and a downstream section, each of the first turbine section and the downstream section having a respective rotating member including at least one stage mounted on a shaft, and each of the first turbine section and the downstream section further having a stationary member surrounding the respective rotating member and defining a steam flow path, a shaft sealing system, the shaft sealing system comprising: at least one seal disposed about each of a first end and a second end of the shaft of the first turbine section and being configured to prevent entry of ambient air into the first turbine section, wherein the at least one seal includes a main seal and a steam seal disposed axially outboard of the main seal, and wherein the at least one seal disposed about each of the first end and the second end of the shaft of the first turbine section comprises a hydrodynamic non-contacting seal comprising a carbon segmented circumferential seal; and a first connection line for conducting steam from the first turbine section to a first stage in the downstream section of the turbine system, the first stage having a lower operating pressure than the first turbine section such that during operation steam is drawn through, the first connection line from a first annulus disposed between the main seal and the steam seal about the first end of the shaft of the first turbine section and a second annulus disposed between the main seal and the steam seal about the second end of the shaft of the first turbine section to the first stage, wherein the downstream section of the turbine system is a distinct turbine section from the first turbine section, the downstream section of the turbine system being one of, a low pressure section of the turbine system, a combined intermediate pressure/low pressure section of the turbine system, or an intermediate pressure section of the turbine system, and the first turbine section being one of, a super high pressure section of the turbine system, a high pressure section of the turbine system, or an intermediate pressure section of the turbine system, and wherein the shaft sealing system does not require the use of a condenser other than a main condenser of the turbine system, and wherein an area about each of the first and the second ends of the shaft of the first turbine section inboard of the main seals are at a pressure greater than atmospheric pressure.