| 摘要 |
PURPOSE:To measure a valve stem clearance easily and correctly by computing the clearance at a guide portion of the valve stem of a steam valve from pressure and temperature signals of the steam leaking from the clearance at the guide portion of the valve stem and pressure and temperature signals of the steam at the inlet and outlet sides of the steam valve. CONSTITUTION:A valve-front temperature detector 35 and a valve-front pressure detector 36 are provided on the upstream side of a steam valve 8 and a valve- back pressure detector 37 is disposed on the downstream side of the valve 8, and further provided is a steam pressure detector 28 of the steam leaking to a draw- out portion of leak steam from valve steam clearance, and the signals from all the detectors are inputted to a valve clearance calculator 38 to compute the valve stem clearance. An alarm device 45 is activated according to the result of the computation. |
