Where does the shaft seal air for this back-pressure steam turbine come from? Also, is this steam seal extractor still in use after the unit is started up?
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Where does the shaft seal air for this back-pressure steam turbine come from? Also, is this steam seal extractor still in use after the unit is started up? Someone who can give a detailed explanation
It is usually taken from the boiler’s main steam, and in some cases from the header
The steam seal extractor must be put into operation after the unit is started up.
Since the cylinders of a back-pressure unit are under positive pressure (the higher the back-pressure, the greater the internal pressure), this causes steam to leak out from the shaft seal locations at both ends. In severe cases, this steam can seep into the bearing housings on either side, posing a risk of oil emulsification. Therefore, to avoid this problem, an axis seal cooler has been added to draw out the steam that may leak from both ends of the axis seal. The device used is called an shaft seal cooler.
So how is this back-pressure steam turbine shut down? Our compressor is driven by a back-pressure turbine; are there any detailed steps, or could you provide a more thorough explanation?