Guide rails: A device made of grooves or ridges made of metal or other materials that supports, secures, and guides moving devices or equipment while reducing friction. The longitudinal grooves or ridges on the surface of a guide rail are used to guide and secure machine parts, specialized equipment, and instruments. Guide rails, also known as slide rails, linear guides, and linear slides, are used in linear reciprocating motion applications. They have higher load ratings than linear bearings and can withstand a certain amount of torque, enabling high-precision linear motion under high loads.

As a guiding device, the guide rail should have the following properties:

(1) Guiding accuracy: This mainly refers to the accuracy of the guide rail's motion trajectory. The main factors affecting the guiding accuracy are: the geometric accuracy and contact accuracy of the guide rail, the structural form of the guide rail, the stiffness and thermal deformation of the guide rail and its supporting parts, the oil film thickness and stiffness between the static (dynamic) pressure guide rail pairs, etc.

(2) Accuracy retention: This is mainly determined by the wear resistance of the guide rail. Wear resistance is related to factors such as the material of the guide rail, the friction properties of the guide rail pair, the pressure on the guide rail and its distribution law.

(3) Stiffness: This includes the guide rail's own stiffness and contact stiffness. It mainly depends on factors such as the shape and size of the guide rail and the connection method with the supporting parts and the stress conditions.

(4) Smoothness of low-speed movement: When the dynamic guide rail moves at low speed or with a small displacement, it is easy to generate friction self-excited vibration, that is, creeping. Creeping will reduce the positioning accuracy or increase the roughness of the workpiece surface.