黄台发电厂4号机负胀差大的原因分析及处理

CAUSE ANALYSIS AND REMEDICAL MEASURES OF LARGER DIFFERENTIAL EXPANSION FOR UNIT NO.4 IN HUANGTAI POWER PLANT

通过分析认为级间蒸汽泄漏和前轴封漏汽的窜流是造成汽轮机负胀差大的主要原因 ,经采取用金属修补剂对 5、6号隔极套和与之相配合的汽缸洼窝进行修补 ,并研磨找平 ,以及消除轴封间隙的不均匀等措施减轻蒸汽的泄漏和窜流 。

Through analysis, it is considered that the main causes resulting in larger differential expansion of a turbine unit are the interstage steam leakage and the fled flow of front shaft-packing's leakage steam. Hence, some remedical measures for reducing steam leakage and fled flow have been taken, namely using metallic mending compound to mend sleeves of diaphragms NO.5 and 6, as well as depresion slots matched with them in the steam casing, grinding and aligning, and eliminating the non-uniformity of shaft-packing's clearance etc., obtaining remarkable effectiveness.