运城发电公司1、2号机组为600MW空冷机组，自投产以来汽机效率远低于设计值。为了提高机组的经济性，采取了一系列增效降耗措施,主要有汽封改造、汽阀内漏治理、调节阀特性曲线及滑压曲线优化、高压调节阀顺阀控制优化等。实施这些措施后，在低负荷工况下，机组的经济性有了很大提高；在大负荷工况下，高压调节阀的节流损失明显减小，提高了高压缸效率。按运城发电公司2010年发电量计算，此项治理获得的经济效益超1 000万元。

The No.1 and No.2 units in Yuncheng Power Generation Company are 600 MW air cooling units, the turbine efficiency of which had been far lower than the design value since operation. A series of measures of efficiency increase and consumption reduction were adopted to improve the units efficiency, such as the reformation of steam seal, the treatment of inner leakage in steam valve, the optimization of control valves characteristic curves and sliding pressure curves, the optimization of sequence valve control for high pressure control valve. After the implementation of these measures, the economy of the units has been greatly improved in low load condition, while the throttling loss of high pressure control valve has been obviously reduced in high load condition so that the efficiency of high pressure cylinder has been increased. According to the electricity generation of Yuncheng Power Generation Company in 2010, the economic benefits obtained from the treatment have exceeded 10 million yuan.