A Brief Talk on the Differences of Three Kinds of Guides in CNC Machining Center

The so-called cnc machining is also called CNC machining, which refers to a kind of machining called cnc numerical control machining by programmers who program the work orders that need to be processed by computer and then operated by cnc machining operators. There are three kinds of guide rails in the cnc machining center. The difference between these three kinds of guide rails is relatively large, so if you need to choose the guide rails of the cnc machining center, it is best to have a detailed understanding of the three guide rails in advance, so that you can better I have chosen a guide rail for my cnc machining center. The following is an introduction to the cnc machining center guide rail:

The guide rails can be divided into linear motion guide rails and circular motion guide rails according to the motion track; according to the nature of work, they can be divided into main motion guide rails, feed motion guide rails and adjustment guide rails; according to the frictional nature of the contact surface, they can be divided into sliding guide rails, rolling guide rails and static pressure 3 kinds of guide rails.

　　 Slide guide

　　Sliding guide rail has the advantages of simple structure, convenient manufacture, good rigidity and high vibration resistance. The traditional cast iron-cast iron, cast iron-quenched steel guide rail has the disadvantage that the coefficient of static friction is large, and the coefficient of dynamic friction changes with speed. The friction loss is large, and crawling is prone to occur at low speed/(1-60mm/min/) The positioning accuracy of the moving parts is reduced, so apart from economical CNC machine tools, it is no longer used on other CNC machine tools.

　　 At present, most CNC machine tools use plastic guide rails, that is, a plastic film soft tape composed of plastic and other chemical materials is stuck on the friction surface of the moving guide rail.

　　Guide rail plastics are commonly used in PTFE rail soft tape and epoxy wear-resistant rail coating. The characteristics of the plastic sliding guide rail are good friction characteristics, good wear resistance, smooth movement, good vibration reduction and good manufacturability.

　　 Rolling guide

　　Rolling guide is to place balls, rollers, needles and other rolling elements between the guide surfaces, so that the sliding friction between the guide surfaces becomes rolling friction. Compared with the sliding guide rail, the advantages of the rolling guide rail are: high sensitivity, and the difference between the dynamic friction and the static friction coefficient is very small, so the movement is smooth, and the crawling phenomenon is not easy to occur when moving at a low speed; The friction resistance is small, the movement is light, the wear is small, the accuracy is maintained well, and the service life is long. However, the vibration resistance of the rolling guide is poor, and the protection requirements are high.

　　 Rolling guide is especially suitable for the occasions where the working parts of the machine tool require uniform movement, sensitive movement and high positioning accuracy. This is the reason why rolling guides are widely used on CNC machine tools.

　　 Static pressure guide rail

There is an oil cavity between the two rail working surfaces of the liquid static pressure rail. After the lubricating oil with a certain pressure is passed, a static pressure oil film can be formed, so that the rail working surface is in pure liquid friction, without wear, and the accuracy is maintained; At the same time, the friction coefficient is also extremely low, which greatly reduces the driving power; low speed without crawling, large load capacity and good rigidity; in addition, the oil has a vibration absorption effect and good vibration resistance. Static pressure guide rail can be divided into liquid static pressure guide rail and gas static pressure guide rail.

The disadvantage of 　　 is that the structure is complicated, and the oil supply system is required, and the cleanliness of the oil is high. Hydrostatic guide rails are increasingly used in machine tools. The hydrostatic guide rail of the CNC turret punch press can be divided into two types: open and closed.