新型气密式油挡在汽轮机的应用与分析

Application and Analysis of New Air-tight Oil Baffle in Steam Turbine

某350MW汽轮发电机组运行过程中汽轮机高中压缸轴承箱油中进水、油挡积碳、轴瓦、转子、主油泵等设备锈蚀的问题,进行了分析诊断。汽轮机由于机组结构原因,前轴承箱油挡属于整体形式,机组检修期间油挡无法进行间隙调整及积碳清理。汽轮机轴封间隙调整不合格及长周期运行对汽封存在磨损,导致汽缸端部汽封漏气,降低汽轮机效率、同时部分蒸汽会从端部流出、恶化工作环境。针对此问题将原油挡技改为新型气密式油挡,该气密式油挡阻止轴封漏汽和灰尘杂质的进入轴承箱内,避免了油中进水和油中带杂质等情况的出现,消除油挡积碳现象。即保证了机组的正常运转,也为今后处理同类型机组出现类似问题提供了参考。

During the operation of a 350 MW steam turbine generator set,the water corrosion,oil deposits,bearing pads,rotors,main oil pumps and other equipment in the high and medium pressure cylin-der bearing box of the turbine were rusted and analyzed.Due to the unit structure of the steam turbine,the oil block of the front bearing box belongs to the overall form.The oil block cannot perform clearance adjustment and carbon deposit cleaning during the unit maintenance.Unsatisfactory adjustment of the shaft seal clearance of the steam turbine and the long-term operation will cause wear on the steam seal,leading to air leakage at the end of the cylinder,reducing the efficiency of the steam turbine,and at the same time,part of the steam will flow out of the end and deteriorate the working environment.In re-sponse to this problem,the crude oil block technology was changed to a new type of air-tight oil block.The air-tight block prevents the shaft seal from leaking steam and dust impurities from entering the bear-ing housing,avoiding water in oil and impurities in the oil.Appears to eliminate oil accumulation.That guarantees the normal operation of the unit,and also provides a reference for dealing with similar prob-lems in the same type of unit in the future.