1. Guiding accuracy

Guiding accuracy refers to the accuracy of the moving track of a moving member when it moves along the guide surface.The main factors affecting the guide accuracy are the geometric accuracy of guide guide surface, the type of guide structure, the contact accuracy, surface roughness, the rigidity of guide and supporting parts, the oil film thickness and oil film rigidity of guide and supporting parts, and the thermal deformation of guide and supporting parts. 

The geometric precision of linear motion guide generally includes: straightness in vertical plane and horizontal plane;Parallelism between the surfaces of two guides.The geometric accuracy of the guide can be expressed as the error of the whole length of the guide or the error of the unit length. 

2. Accuracy maintenance

Accuracy retention is the ability to keep the original geometric accuracy in the working process of the track.The accuracy retention of guide mainly depends on the wear resistance and dimensional stability of guide.The wear resistance is related to the material matching, stress, machining accuracy, lubrication mode and the performance of the protective device. In addition, the residual stress in the guide and its supporting parts will also affect the accuracy retention of the guide. 

3. Motion sensitivity and positioning accuracy

The motion sensitivity refers to the minimum stroke that a moving member can achieve.Positioning accuracy refers to the ability of a moving member to stop at a specified position as required.The motion sensitivity and positioning accuracy are related to the type of guide rail, friction characteristics, motion speed, transmission stiffness, and the quality of moving components. 

4. Stationary motion

The motion smoothness of the guide rail is the performance that the guide rail does not creep when moving at low speed or moving at a small amount.The stationarity is related to the structure of the guide, the matching of the guide material, the lubrication condition, the lubricant property and the rigidness of the transmission system. 

5. Vibration resistance and stability

Vibration resistance refers to the ability to guide the rail pair to withstand forced vibration and impact, while stability refers to the performance of no self-excited vibration under given operating conditions. 

6. Stiffness

The resistance of a guide to deformation under force.Deformation will affect the relative position and guiding accuracy of components, which is particularly important for precision machinery and instruments.Deformation of guide includes deformation of guide body and contact deformation of guide pair, both of which should be considered. 

7. Process of structure

The manufacturability of the structure is the degree of difficulty to process the guide rail pair (including the member where the guide rail pair is located).On the premise of meeting the design requirements, it is necessary to make the manufacturing and maintenance as easy as possible with low cost.