STEAM CHEST OF GEOTHERMAL TURBINE, GEOTHERMAL TURBINE WITH STEAM CHEST AND GEOTHERMAL TURBINE STEAM SUPPLY METHOD

摘要

PROBLEM TO BE SOLVED: To reduce occurrence of repeated load for a row of rotor blades of an initial stage turbine by a method in which steam can be supplied uniformly from both initial stage nozzle ports at a main steam chest and a sub-steam chest along a peripheral direction of the initial stage turbine when the sub steam chest is operated.SOLUTION: A steam chest 21 of a geothermal turbine 1 comprises an annular steam chest casing 4 enclosing a turbine rotor 3 and formed with first stage nozzle ports 8a along its peripheral direction; partition walls 11, 12 for defining an inside part of the steam chest casing 4 into a main steam chest 14 and a sub-steam chest 15 having a smaller volume than that of the main steam chest 14; a main steam pipe 18 for supplying geothermal steam to the steam chest casing 14; a sub-steam pipe 19 connecting the main steam chest 14 with the sub-steam chest 15 and distributing a part of the geothermal steam supplied to the main steam chest 14 to the sub-steam chest 15; and on-off valve 20 arranged at the sub-steam pipe 19. The partition walls 11, 12 can change their fixing positions at a peripheral direction of the steam chest casing 4.SELECTED DRAWING: Figure 2