VALVE ARRANGEMENT HAVING TWO VALVES IN A COMMON HOUSING AND USE OF THE ARRANGEMENT IN A VAPOR GENERATING AND UTILIZING PLANT

摘要

A steam generation plant comprises a valve 71 including two passages BT and BTB, see Division F2, to prevent the transfer of water direct from an evaporator 70 to a superheater 72. In operation, when the plant is started up, feed water is pumped from a tank 80, via a preheater 67 and economizer 68 to the evaporator 70. Valves 71 and 82 are closed. At a preset pressure valve 82 opens, and fluid flows to the separator 83. Vapour passes via the superheater 72 to turbines 74 and 76. When the pressure builds up, valve 82 is closed and passage BTB in the valve 71 is opened, until the plant reaches full load whereupon the passage BT is opened.