CONTROLLER FOR WATER-LEVEL OF BOILER DRUM

摘要

PROBLEM TO BE SOLVED: To provide a controller for water-level of a boiler drum, in which water-level control of a boiler drum can be continued automatically, irrespective of the length of shutdown time of a plant.;SOLUTION: In order to spread the level-control range from a normal range A to a lower part B, detection positions are provided in the pipe from an existing downcomer 3 and the drum 1 to a run-out main valve 42. Detection pipes 63 and 64 are newly provided to detect a differential pressure between them with a differential-pressure oscillator 72. Thus, even if a water level goes over the lower control limit of the level control range A, the level control can be continued in the level control range B.;COPYRIGHT: (C)2002,JPO