Spring testing machine is a special instrument for testing springs. It is mainly divided into three categories: spring tension and compression testing machine, spring torsion testing machine and spring fatigue testing machine.

For small-load springs, especially high-rigidity precision springs, the first thing is to ensure that the equipment has high test accuracy, because a small change in displacement will cause a large deviation in the test force, and ensuring the test accuracy of the test force can be achieved with a little attention. However, it is more difficult to ensure the accuracy of another parameter displacement of the spring testing machine, which is the standard used in the industry to judge the accuracy of spring testing machines. Therefore, many people in the industry use the accuracy of displacement testing as a benchmark to judge the level of testing machines.

In the national standard of spring tester, the displacement accuracy requirement is relatively small, which cannot meet the needs of high-rigidity precision springs. Therefore, for manufacturers, it is necessary to improve the displacement test accuracy to ensure the needs of users. There are many reasons that interfere with the displacement test accuracy, such as detection method, overall machine structure, overall machine stiffness, parallelism of the pressure plate, measuring elements, materials, load displacement sinking, etc. If these problems can be solved, the displacement accuracy can be guaranteed.