机械式全调节水泵抬机及其原因分析

Cause analysis of lift-unit problem happening at axial pump with mechanical adjustable blades

抬机是水泵运转中经常出现的故障之一,发生机理较为复杂,影响因素很多,如进水池的水位变幅突然增大等.机械式全调节水泵在某些工况运行时因机械调节机构本身的原因也会发生抬机,尤其是往正角方向调节叶片角度时.从受力分析角度出发,以16CJ-80型机械式全调节水泵为例,对其叶片系统进行详细的受力分析,针对不调叶片安放角、往正角方向调、往负角方向调3种情况进行力学计算.经对比分析,得出结论:机械式叶片调节机构的受力方式是引发抬机的一个内因,机组推力轴承受力的突变是引发机组抬机的根本原因.因此,改善机械式叶片调节机构的受力,可以有效解决水泵机组的抬机问题.

Lift-unit problem is one of faults during operation of pump unit,having complex mechanism,determined by various agents,such as raise of water level amplitude in suction sump as a outside factor.It occurs when axial pump with mechanical adjustable blades operates under some conditions,especially when a positive blade angle adjustment is given.Taking a pump of 16CJ-80 for example,to solve this lift-problem,in terms of force analysis of blade system,a mechanical calculation is given in three kinds of conditions including no adjusting,adjusting towards positive angle,and adjusting towards negative angle.After a comparative analysis,it is found that the force mode of mechanical blade adjusting device is one of internal causes for lift-unit problem;and sudden change of force on thrust bearing in pump unit is the root cause.It is a good solution to improve the force mode of the device.