Maintenance And Sharpening Of Paper Cutting Machine Blades

Blade grinding
The cutting performance of mechanical blades largely depends on the grinding quality, which in turn depends on the grinding equipment and reasonable grinding process. Blade grinding equipment, it is recommended to use a vertical shaft type blade grinder, as the angle of the blade is easy to ensure. It is recommended to choose white alumina (code WA) as the grinding wheel. It is not easy to generate heat during grinding, and cooling liquid must be continuously poured on the contact surface between the cutting edge and the grinding wheel during grinding. It is strictly prohibited to overheat and discolor the cutting edge. It is recommended to use No.1 metal emulsion. The entire blade grinding process is best divided into rough grinding, fine grinding, and finishing. Rough and fine grinding are carried out on a knife grinder, and finishing requires both a knife grinder and manual operation.
The steps for finishing are:
1. It is considered that the blade has been ground (no sparks are visible), and there is no need to give the feed rate. Let the grinding machine repeat several strokes on its own, and the number of strokes depends on the length of the blade. If it is short, the stroke will be reduced.
2. Remove the blade from the sharpener and use an oilstone for manual grinding to obtain excellent sharp edges. The method is to gently remove the small burrs generated by the sharpener on the blade edge using an oil soaked oilstone, and then rotate the oilstone tightly against the front blade surface to move it to the full length of the blade.
3. Use the same method to move the oilstone to the full length of the blade after fine grinding, but tilt the oilstone slightly at an angle of no more than 1 °. After grinding according to the above method, an ideal blade is considered complete.
Wedge angle, also known as blade angle, is the main angle that directly affects cutting performance, and the size of the angle depends on the cutting object.
Paper cutting machines are essential equipment for printing enterprises and are widely used in various industries such as printing and publishing, paper making, packaging, and decoration. Its most basic function and application is cutting. The final executing component of cutting is the blade. On the one hand, the quality and reasonable use of the blade directly affect the cutting quality, and on the other hand, unreasonable blade grinding angles and use can seriously damage the accuracy and lifespan of the paper cutting machine. So maintaining and sharpening the blades is the first step in the application and maintenance of paper cutting machines.
Material and composition of paper cutting machine blades
The blade of a paper cutting machine is made of two parts: the blade and the blade body, which are welded at high temperature. The blade part is usually made of HSS (High Speed Steel) or high hardness chromium tungsten manganese CrWMn steel, with some using hard alloys. The blade body is usually made of low-carbon steel. After quenching the blade, the hardness of the blade can reach 60-64HRC.