Hardware Knowledge Base: "Torque Wrench"

Torque wrenches - also called torque wrenches or torque wrenches, torque is the product of force and distance. When tightening screw fasteners such as bolts and nuts, it is necessary to control the magnitude of the applied torque to ensure that the threads are fastened and will not be subject to torque. Large damage to the thread, so use a torque wrench to operate. First set a desired upper torque value. When the applied torque reaches the set value, the wrench will issue a "Kata" sound or the wrench joint will bend a little at an angle. This means that no tightening has been done.

working principle

The principle of issuing a Kata sound with a torque wrench (torque wrench) is simple and can be divided into the following steps to understand:

1. After the "Kata" sound is issued by the torque wrench, it indicates that the torque value you have reached has been reached;

2. The “Kata” issued by the torque wrench is generated by its own internal torque release structure. Its structure is divided into three structures: a pressure spring, a torque release joint and a torque jack.

3. First, set the required torque value on the torque wrench (pressed by the spring sleeve on the top rod to the torque release joint), lock the torque wrench, and start tightening the bolt. When the bolt reaches the torque value (when the torque is greater than the spring pressure), there will be an instantaneous disconnection effect. At the moment when a disjointed effect occurs, a joint strike is made and the “Kata” sound from the metal casing of the wrench is emitted. From this, we can confirm the reminding effect of reaching the torque value (actually the same principle as when we put the 15 degree bend of the arm joint into the iron pipe and then immediately hit the steel pipe).

The above is the most commonly used manual torque wrench, in addition to electric torque wrenches, pneumatic torque wrenches and so on.

structure

Torque wrenches are also called torque meters and torque screwdrivers. It is based on the bending principle of the beam, the bending principle of the torsion bar and the compression principle of the coil spring and can measure the magnitude of the moment acting on the nut. Torque wrenches are available in flat and dial type.

The torque wrench has a long elastic rod with a handle at one end and a square or hexagonal head at the other end. A replaceable sleeve is set on the square or hexagonal head and caught in a steel ball. There is also a long pointer on the top. The scale plate is fixed on the handle and the scale value is 1N (or kg/m). Before use, first adjust the indicator installed on the wrench to the required torque, and then pull the wrench. When the predetermined torque is reached, the pointer on the indicator will turn to the pin side, and finally the pointer collides with the pin. , Inform the operator via speaker signal or sensor signal.