Shorting closing time of steam valve for turbine - converting changing number of revolutions of rotation counter into inversely-proportional impulse pressure

摘要

The closing time of a steam valve for a steam turbine is reduced by a sudden decrease in load. The changing number of revolutions of a rotation counter is converted into an impulse pressure inversely proportional to it. The adjusting piston of the valve (11) is set in dependence in the change in oil pressure in the impulse control line (17). The latter is assigned to a differential control (15) switched in parallel to the revolution control (12, 32). The differential control can be for an hydraulic steam turbine control. In which case, an oil chamber is divided into two volumes by a separating piston slidable against the force of a biasing spring.