Torque wrench is one of the important force measuring tools to ensure the connection quality of reinforcement. Its structure is shown in Figure 3-24 and its technical performance is shown in table 3-16. When operating the torque wrench, first adjust the wrench according to the torque value specified for different reinforcement diameters, and then tighten the reinforcement with the connecting sleeve. When the required torque is reached, an audible signal can be sent out.

(1) Usage of torque wrench. The traveling scale of the row torque wrench is usually set at the lowest position. When in use, rotate the adjusting screw rod with an adjusting wrench according to the diameter of the connected reinforcement, align the scale value of the reinforcement diameter on the swimming scale with the scribed line on the handle shell, then bite the tong head vertically on the connected reinforcement, hold the handle of the torque wrench by hand, and apply force evenly clockwise. When the torque wrench makes a “click” sound, the reinforcement connection reaches the specified torque value. Stop the force application, otherwise the torque wrench will be damaged. The counter clockwise rotation of the torque wrench only acts as a ratchet and cannot apply force. When the torque wrench has no sound signal, it shall be stopped and repaired; The repaired torque wrench can only be used after calibration.
(2) Precautions for use of torque wrench
① Prevent water, mud and sand from entering the handle.
② The torque wrench shall be flat, and the tong head shall be perpendicular to the reinforcement, and the force shall be applied evenly without excessive force.
③ When the torque wrench makes a “click”, do not continue to apply force to avoid overloading and bending the wrench.
④ Do not use the torque wrench as a hammer or crowbar to avoid damaging the torque wrench.
⑤ When the torque wrench is not applicable for a long time, the scale value of the traveling scale of the torque wrench shall be adjusted to 0 to prevent the compression spring in the handle from being pressed for a long time and affecting the accuracy of the torque wrench.