| 摘要 |
PROBLEM TO BE SOLVED: To solve such a problem that the thicknesses of a main steam pipe near a main steam relief valve and a valve connecting nozzle stub are increased to decrease a response acceleration of the main steam relief valve, on this occasion, though the wall thickness of a regular JIS pipe increases in the direction of reducing the inner diameter, the inner diameter decreases to possibly cause acoustic vibration, and a relieving capacity of the main steam relief valve decreases to cause a decrease in a turbine inlet end pressure. SOLUTION: The wall thickness is increased in the direction of increasing the outside diameter of a pipe system to retain the inner diameter conventionally so as to have a structure capable of eliminating any influence on the acoustic vibration in the pipe and relieving capacity of the main steam relief valve. Alternatively, the wall thickness is increased in the direction of increasing the outside diameter of the pipe (application of pipes out of IS standard) so as to have a structure capable of eliminating any influence on the acoustic vibration and the turbine inlet end pressure. COPYRIGHT: (C)2012,JPO&INPIT |
