Linear bearing models are generally composed of front code, basic code and rear code. Generally, the bearing model is only represented by the basic model. The basic model generally includes three parts: type code, dimension code and inner diameter code. The post code refers to the special requirements of bearing structure, tolerance and material with letters and numbers. The leading code is used to indicate the sub parts of the bearing and is represented by letters. Code method for universal bearings (rolling bearings). It is divided into: pre code, basic code and post code. Linear bearing is a linear motion system, which is used for linear stroke and cylindrical shaft. As the bearing ball contacts with the bearing outer sleeve, the steel ball rolls with the minimum friction resistance, so the linear bearing has small friction and is relatively stable. It does not change with the bearing speed, and can obtain a stable linear motion with high sensitivity and high precision. Linear bearing consumption also has its limitations. The most important is that the impact load capacity of the bearing is poor, and the bearing capacity is also poor. Secondly, the linear bearing has large vibration and noise when moving at high speed.