Selection and design of the hottest guide rail

Selection and design of guide rail

the main function of guide rail is guidance and bearing. The guide rail makes the moving parts move along a certain track, so as to ensure the relative position accuracy between the parts. The guide rail is mainly composed of a pair of guide rail pairs with the cooperation of two relatively moving parts on the machine tool, which means that the keynote of the "green" development of the industry will further strengthen the coordination of immobility, which is called the supporting guide rail, and the coordination of movement, which is called the moving guide rail. The guide rail can be divided into linear motion guide rail and circular motion guide rail according to the motion track; According to the friction property, it can be divided into sliding guide rail and rolling guide rail. Among them, rolling guide rail is divided into ordinary sliding guide rail, liquid dynamic pressure guide rail and liquid static pressure guide rail. According to the shape of rolling element, rolling guide can be divided into ball guide and roller guide. The rolling guide rail is widely used in the feed motion guide rail. Because our design is the chute box feeding system of the CNC gantry boring and milling machine. The CNC gantry boring and milling machine is a heavy-duty machine tool with large bearing capacity and good guidance accuracy requirements, so we can choose the cut-off double rectangular combined guide rail. At the same time, the plastic rolling guide rail has good positioning accuracy and movement stability, convenient maintenance and repair, and good economy. We can use the stick dog guide rail. The CNC gantry boring and milling machine bears a large overturning torque, so it adopts the form of closed guide rail, so it chooses to stick the guide rail. The sticking dog guide rail is to stick a layer of wear-resistant plastic guide rail soft belt on the sliding guide rail to quench and grind the matching guide rail. The plastic guide rail soft belt is made of polytetrafluoroethylene as the base material, adding alloy powder and oxide. The plastic guide rail soft belt can be cut into any size and shape, and bonded to the guide rail base with adhesive. Because this kind of guide rail soft belt is processed by bonding method, it is called bonding guide rail. The soft belt of plastic guide rail is a composite material composed of "storer said polytetrafluoroethylene PTFE as the matrix, adding bronze powder, molybdenum disulfide, graphite and other fillers. Under oil lubrication, its friction coefficient is about 0.06, and its service life is 8 ~ 10 times that of ordinary cast iron

guide rail. The plastic guide rail soft belt has various thickness specifications, and the length and width are cut by the user and determined by pasting. Compared with other guide rails, the plastic guide rail soft belt has the following characteristics:

(1) the friction coefficient is low and stable, which is one order of magnitude lower than the cast iron guide rail pair

(2) the dynamic and static friction coefficients are similar, and the motion stability and creepability

can be better than cast iron guide rail pairs

(3) it absorbs vibration and has good damping characteristics, which is better than the rolling guide rail with thick screw root and the static pressure guide rail that is easy to float with low contact stiffness

(4) good wear resistance, self lubrication, working without lubricant, good embedding of dust and abrasive particles

(5) good chemical stability, low temperature resistance, strong acid, strong alkali, strong oxidant and various organic solvents

(6) it is easy to maintain and repair, the soft belt is wear-resistant, and it is easy to replace after damage

(7) good economy, simple structure and low cost, about 1/20 of the cost of rolling guide rail