M701F4燃气轮机TCA系统冷却水流量异常分析

Abnormal Analysis of Cooling Water Flow in TCA System of M701F4 Gas Turbine

三菱M701F4燃气轮机采用透平冷却空气(TCA)系统冷却转子高温部件,TCA系统冷却水流量减少,将导致TCA冷却器出口空气温度的升高,从而威胁到转子高温部件的正常工作。针对一起TCA冷却器水异常事件,通过对透平控制系统、TCA冷却水回余热锅炉和回凝汽器两种不同的流量控制策略的分析,找出了该异常的原因为压力变送器引压管结冻。并针对该类型异常提出了加强变送器日常维护、改善变送器及引压管的保温状况等措施。

The Mitsubishi M701F4 gas turbine adopts the turbine cooling air(TCA)system to cool the high temperature parts of the rotor.The reduction of the cooling water flow in the TCA system will lead to the increase of the air temperature at the outlet of the TCA cooler,thus threatening the normal operation of the high temperature parts of the rotor.Aiming at an abnormal TCA cooler water event,through the analysis of two different flow control strategies of the turbine control system,the TCA cooling water return to the waste heat boiler and the return condenser,it is found that the cause of the abnormality is the pressure transmitter The pressure tube is frozen.In view of this type of abnormality,measures such as strengthening the routine maintenance of the transmitter and improving the thermal insulation of the transmitter and the pressure implanting pipe are proposed.