低背压下某叶片的测温试验

Temperature Test of a Blade under Low Back Pressure

汽轮机末级叶片在没有冷却蒸汽的条件下运行时,由于鼓风效应其叶片顶部表面温度随背压的升高而升高。某汽轮机末级叶片在动平衡筒体内进行了简单的测温试验,在叶片顶部表面粘贴测温试纸,观察同样的转速和时间下不同背压时测温试纸的数值,结果表明随着背压的升高叶片表面温度开始剧烈上升随后变化较慢,根据测温结果认为叶片在真实背压工况下不可能被允许运行。

The surface temperature of the top of the turbine blade increases with the increase of the back pressure due to the wind blast effect when the L0 blade of the turbine is operated without cooling steam. A simple temperature test is carried out on L0 blade of a steam turbine in the body of the dynamic balance cylinder. The temperature test paper is affixed to the top surface of the blade to observe the value of temperature test paper at different backpressure under the same speed and time. The results show that with the increase of back pressure, the surface temperature of the blade begins to rise sharply and then changes slowly. According to the temperature measurement results, it is considered that the blade can not be allowed to operate under real back pressure.