Commissioning of the steam turbine shaft seal air supply
Thread Content
1. Differences between starting up the shaft seal air supply in a cold and hot state of the turbine. 2. Differences between starting up closed-type shaft seal air supply and open-type shaft seal air supply. In other words, when the turbine’s shaft seal air supply is of the open type, are there any differences between starting it up in a cold state and a hot state? For a closed-type shaft seal, what is the difference in putting it into use when the system is at cold conditions versus hot conditions? Can the cold and hot states be brought online using the same method?
I’ve done both; I can’t remember what the difference is. In either case, the oil system’s barring gear has to be activated before the unit can be put into operation. The open-style operation manual states that the unit should not be started within two hours, and the shaft seal steam supply must be stopped
For condensing units, evacuation and startup are carried out first in the cold state, followed by the installation of the shaft seal; in the hot state, the shaft seal is installed first and then evacuation is performed. The purpose is to prevent uneven heating of the main shaft caused by installing the shaft seal first, which could lead to vibrations.