Torsional springs are usually close-fitting, but the springs are spaced to reduce friction. They exert resistance to rotation or rotational forces. According to the application requirements, the design of torsion spring rotation (clockwise or counterclockwise), so as to determine the spring rotation. The thickness of the spring wire should be selected according to the size of the necessary spring force. Usually represented by the letter d. It is also necessary to understand the cross-sectional diameter of the torsion spring. The natural length of the torsion spring and the maximum torsion angle of the torsion spring. Only by calculating the maximum force that the torsion spring can support can the service life of the torsion spring be extended. It is also necessary to understand the maximum load of different torsion springs, and then you can choose the spring according to your own needs. Special attention should be paid to the spiral direction of the spring, which is the most common mistake area in our daily life. People often misremember the direction of rotation. So this must be kept in mind.