Pine nut originated in foreign countries. It is a special engineering plastics permanently attached to the thread, the thread in the internal and external tightening process, engineering plastics extrusion and produce strong counterforce. The friction force between the inner and the outer threads is greatly increased, and the absolute resistance to vibration is provided.

This resistance is fully distributed in the screw thread of the mesh, and the friction between internal and external thread tightening pressure independent, different from the previous stopping method, friction on the screw tightening after the pressure generated from the stop function, once the screw slightly loose, pressure reducing, friction which is rapidly disappearing and lost the stop function, so that the screw loose. However, it is necessary to explore a kind of new technology to prevent loosening of plastic, which can not meet the requirements of high temperature and cold.

In the 35 years before the Spiralock nut was invented in the United States, has a 30 degree wedge in the traditional 60 degree cusp tip, this structure makes the bolt after tightening with Spiralock nut thread between yin and Yang, will have greater friction compared to the traditional thread, in order to achieve the looseproof.

Due to the change of the angle of the tooth, the normal force generated by the contact between the threads is 60 degrees angle with the bolt axis, but not the same as the common thread angle of 30 degrees. Spiralock thread fastening pressure is far greater than the normal pressure. Therefore, the anti friction force will be greatly increased. Yang and Yin on top of thread Spiralock thread, at the top of the tooth tip deformation, the load is evenly distributed in the spiral line contact length, to avoid the ordinary standard thread, the total load of more than 80% concentration in the role in the first and second threads on the surface of the teeth. Therefore, Spiralock thread connection pair is not only to overcome the common standard connection side under vibration condition is easy to loose from the shortcomings, but also can prolong the service life.

As a result of this special form of tooth decay prevention, the repeatability can be removed from 5 to 50 times, and the function of anti loosening will still exist for a long time. Because of this anti loose way has high vibration, portable, repeatable disassembly. It has become the most reliable anti loose product.

After sanforizing screw is called locking screws, the most suitable fastening applications in moving parts, the use of space aircraft as early as in the United States, and later extended to the U.S. auto industry, with the mature technology and lower manufacturing cost, is widely used in 3C, bicycle, skating and skiing equipment, furniture, sports equipment medical equipment and other industries, a comprehensive check washer to replace the traditional, fully displays the fastening nut screws loose proof effects of trustworthiness.