Linear bearing is a linear motion system, which is used in line travel with cylindrical shaft. Due to the contact between the bearing ball and the bearing coat point, the steel ball rolls with the minimum friction resistance. Therefore, the linear bearing has small friction and is relatively stable, and it does not change with the bearing speed, so it can get a high sensitivity and high accuracy straight line motion. Linear bearing consumption also has its limitations. The most important thing is that the bearing impact load capacity is poor, and the bearing capacity is also poor. Secondly, the linear bearing has larger vibration and noise when moving at high speed. Fast and easy selection of linear bearings is included. Linear bearings are widely used in the sliding parts of industrial machinery, such as precision machine tools, textile machinery, food packaging machinery, printing machinery and other industrial machinery. 
Due to the contact of the bearing ball with the bearing point, the load is small. The steel ball rotates with minimal friction resistance, thus obtaining high precision stationary motion.
Plastic linear bearing is a kind of self lubricating
characteristics of linear motion system, the biggest difference is that
the metal and metal linear bearings, linear bearings are rolling
friction between the bearing and the cylinder axis is point contact, so
it is suitable for low load and high speed motion; linear bearing is
plastic sliding friction between bearing and shaft, cylindrical surface
contact so, this is suitable for high load low speed.