在机车修理生产中,许多卸装作业迄今尚未实现机械化,完成这些作业需要付出大量的体力劳功并花费很多时间。例如,柴油机曲轴主轴承盖螺母、牵引电动机端盖螺栓、转向架构架端部螺母及其他一些部件螺母的松紧均使用螺母扳手和专用长扳手以手工方式来完成。在上述作业中使用风动螺母扳手受到限制的主要原因是:扭矩不够和外形尺寸较大。 In locomotive repair production, many unloading operations have so far not been mechanized, requiring a significant amount of physical labor and time to complete these operations. For example, the crankshaft main bearing nut of diesel engine, traction motor cap bolts, end frame of the bogie frame and some other parts of the nut are loosened by hand using a nut wrench and a special long wrench. The main reasons that the use of a pneumatic nut wrench is limited in these operations are: inadequate torque and large form factor.