Align the bolt and pull the power switch. The electric shear wrench is mainly used to tighten the shear type high-strength bolt. It is used to pull the power switch against the bolt until the box head of the shear type high-strength bolt is broken.

定转矩电动扳手的转矩以电气装置来进行控制。这种电动扳手具有耗电量少、噪声小、调节灵活、能自动停机、转矩稳定等优点。

The torque of constant torque electric wrench is controlled by electrical device. The electric wrench has the advantages of less power consumption, low noise, flexible adjustment, automatic stop, stable torque, etc.

针对螺栓可能存在的缺陷（如裂纹，夹渣，混料等）磁导率和钢铁磁导率的差异，磁化后这些材料不连续处的磁场将发生崎变，形成部分磁通泄漏处工件表面产生了漏磁场。

In view of the difference between the magnetic permeability of the bolt (such as crack, slag inclusion, mixture, etc.) and that of the steel, the magnetic field at the discontinuity of these materials will change after magnetization, forming a magnetic leakage field on the surface of the workpiece at the part where the magnetic flux leaks.

当螺母的端面与工件端面接触后，阻力矩急剧上升，转动的螺旋槽使滚珠带着主动冲击块克服摩擦力和工作弹簧的压力向后移动，使主动冲击块与从动冲击块互相啮合的牙脱离啮合。此时，从动冲击块不移动，而主动冲击块继续向后移动。

When the end face of the nut contacts the end face of the workpiece, the resistance torque rises sharply. The rotating spiral groove makes the ball move backward with the active impact block to overcome friction and the pressure of the working spring, so that the teeth that the active impact block and the driven impact block mesh with each other are disengaged. At this time, the driven impact block does not move, while the active impact block continues to move backward.

在转过从动冲击块的牙后，由于工作弹簧的作用使主动冲击块瞬时前移，并沿螺旋槽产生一个角加速度，主动冲击块撞击从动冲击块，两牙产生碰撞。然后螺旋槽又使滚珠和主动冲击块后移，脱离啮合。这样周而复始产生一次又一次的碰撞，获得所需的冲击力矩，使螺母紧固。

After rotating the tooth of the driven impact block, the active impact block moves forward instantaneously due to the action of the working spring, and produces an angular acceleration along the spiral groove. The active impact block impacts the driven impact block, and the two teeth collide. Then the spiral groove makes the ball and the active impact block move backward and disengage from engagement. In this way, repeated collisions are generated to obtain the required impact torque and tighten the nut.