The function of the shearing machine guide is to guide and load. Its accuracy has a great influence on the performance of the shearing machine. High guiding precision and good lasting accuracy are the two major requirements for the shearing machine guide. The guiding accuracy guarantees the accuracy of the guide rail movement, which is the prerequisite for ensuring the working quality of the guide rail; the lasting precision refers to the ability of the guide rail to continue to maintain high-quality work. It is mainly determined by the wear resistance of the guide rail, the friction properties of the guide rail, and the guide rail material. , Processing technology and force conditions, but the theory and practice have proved that the main factor affecting the lasting accuracy is wear, so improving the wear resistance of the guide rail to maintain accuracy is one of the main tasks to improve the quality of the shearing machine.
1 The correct choice of materials and manufacturing processes to improve the lasting precision of the guide rail
1.1 Correct selection of materials
Choosing the right material can improve the wear resistance of the guide rail. There are two commonly used materials and processing methods. One is to choose a cast iron material. The guide rail surface is quenched. The hardness after quenching is very high. The hardened layer can reach 1 to 3 mm, and the hardness can reach HRC45～53, the wear resistance is 2～2.5 times higher than that of non-quenched guide rails; another method is to use inlaid steel guide rails. The processing of inlaid steel guide grooves generally uses planing. After the guide grooves are planed, the guide rails are fixed on the bed first. After fine grinding, its wear resistance is much higher than that of surface-quenched cast iron guide rails, and its lasting accuracy is also better.
1.2 Choosing the appropriate processing technology The appropriate processing technology can improve the wear resistance of the guide rail. The methods of finishing the guide rail mainly include precision planing (or precision milling), grinding and scraping. Precision planing is generally used for the guide rail surface of a large bed. This method has high production efficiency and good processing quality. Because the planer cuts one-way, the processing pattern is consistent with the movement direction of the bed guide rail, so the wear resistance is good. The key to improving the quality of guide rail planing is the adjustment of the shearing machine, the installation and sharpening of the cutting tools, and the selection of the cutting amount. The precision planer is generally a wide-edged shaped planer, and the cutting amount is smaller than that of ordinary planing. In order to reduce the surface roughness value, kerosene continuous cooling and lubrication is generally used.
Hardened guide rails are not suitable for precision planing. For hardened guide rails, grinding is more suitable, and it is the processing method of hardened guide rails. Because the grinding can realize the micro-feed, the machining accuracy and surface quality are better, the production efficiency is higher, and the manufacturing accuracy of the guide rail can be guaranteed.
