There are mainly three types of guide rails in CNC machining centers, which can be divided into static pressure guide rails, sliding guide rails, and rolling guide rails according to the conflict nature of the contact surface. The differences between these three types of guide rails are quite significant, and it is important for everyone to have an understanding of them when performing CNC machining. Below, the editor will briefly introduce their advantages and disadvantages.

The advantages of the three are as follows:

CNC machining of aluminum parts

1. There is an oil chamber between the two working surfaces of the liquid static pressure guide rail. After lubricating oil with a certain pressure is introduced, a static pressure oil film can be formed, causing the surface of the guide rail to be in pure liquid conflict, without wear, and with good accuracy retention; Together, the conflict coefficient is also extremely low, greatly reducing the driving power; Low speed without creeping, with high load-bearing capacity and good stiffness; In addition, the oil has a vibration absorption effect and good vibration resistance. Static pressure guide rails can be divided into liquid static pressure guide rails and gas static pressure guide rails.

2. Sliding guide rails have the advantages of simple structure, convenient production, good stiffness, and advanced vibration resistance. There are two commonly used types of plastic for guide rails: polytetrafluoroethylene guide rail soft belts and epoxy wear-resistant guide rail coatings. The characteristics of laminated sliding guide rails are good conflict characteristics, good wear resistance, smooth movement, good vibration reduction, and good craftsmanship.

3. Rolling guide rail is a type of guide rail that places rolling elements such as balls, rollers, and needles between the guide rail surfaces, turning sliding conflicts between the guide rail surfaces into rolling conflicts. Compared with sliding guide rails, rolling guide rails have the advantages of high flexibility and minimal difference in dynamic and static conflict coefficients, resulting in smooth motion. When moving at low speeds, they are less prone to crawling; The positioning accuracy is high, and the repeated positioning accuracy can reach 02um. The collision resistance is small, the movement is simple, the wear is small, the accuracy retention is good, and the service life is long. However, the anti vibration performance of the rolling guide rail is poor, and the protection requirements are high.

What are the drawbacks of the three?

1. The disadvantage of static pressure guide rail is its disorderly structure, which requires a fuel supply system and high cleanliness of the oil. Hydrostatic guide rails are increasingly widely used in machine tools. The liquid static pressure guide rails of CNC turret punching machines can be divided into two categories: open and closed.

2. The disadvantage of sliding guides is that they have a large static conflict coefficient, and the dynamic conflict coefficient changes with speed, resulting in a large conflict loss. At low speeds (1-60mm/min/), they are prone to crawling, which reduces the positioning accuracy of moving parts. Therefore, they are no longer used in other CNC machines except for economical ones. At present, most CNC machine tools use plastic guide rails, which means that a layer of plastic film soft tape composed of plastic and other chemical materials is pasted on the conflicting surface of the moving guide rails.

3. The disadvantages of rolling guide rails are small damping, easy to cause overshoot or oscillation, low stiffness, difficult manufacturing, and sensitivity to dirt and rail surface errors. Rolling guide rails are particularly suitable for situations where the operating components of machine tools require uniform movement, flexible movement, and high positioning accuracy.