Sanding belts and polishing belts are widely used in many machinery manufacturing industries. Today, Binic abrasive- abrasive sanding belts suppliers will introduce the analysis and characteristics of sanding belt grinding.
Grinding analysis
Grinding, like general cutting, uses abrasive grains as tools to cut wood. The formation of wear debris also undergoes the process of elastic and plastic deformation, as well as the generation of force and heat.
Grinding characteristics
The grinding process is more complicated than the general cutting process because it has the following characteristics:
- Each cutting edge of abrasive grains is equivalent to a basic cutter, but since most abrasive grains are cut with negative rake angle and small relief angle, the cutting edge has an arc radius of -um, so the cutting edge is suitable for processing during grinding. The surface is scraped and squeezed, causing strong deformation of the wood in the grinding area. especially the blade
After dulling, the deformation of the chip and the machined surface is more serious relative to the very small chip thickness (usually a few microns).
- The blades of the abrasive grains are arranged irregularly on the wide sanding belts. Although the average distance between the cutting edges can be calculated according to the organization number and particle size of the abrasive tool, the cutting edges of each abrasive grain are not all on the same circumference or At the same height, therefore, the cutting conditions of each abrasive particle are not the same. in,a relatively protruding and relatively sharp cutting edge can obtain a large cutting thickness, while some abrasive grains have a very thin cutting thickness, and some abrasive grains can only rub and dent on the surface of the workpiece, so the resulting chip shape Very irregular.
During grinding, due to the blunt cutting edge of abrasive grains, high grinding speed, large chip deformation, and severe pressure and friction of the cutting edge on the sanding belts for woodprocessing surface, it leads to a large number of heating and high temperature in the grinding area. The wood itself has poor thermal conductivity, so the machined surface will be burnt. Binic manufactured 4×36 sanding belt 3000 grit.
Abrasives themselves
Also dulls faster. The way to reduce the grinding heat is to choose the abrasive tool reasonably. The hardness of the abrasive tool should be appropriate, too hard, and the abrasive particles are not easy to fall off after becoming dull, and they squeeze and rub on the processing surface, which will rapidly increase the grinding temperature. The tissue should also not be too tight to avoid clogging of the abrasives. In addition, it is necessary to control the grinding depth. If the depth is large, the grinding thickness will increase, which will also increase the grinding heat. In order to accelerate the heat dissipation, in the broadband sander, compressed air is used for cooling or spiral grooves are formed on the surface of the sand roller. When the sanding belt cleaner is rotating at high speed, it should be cooled by air circulation.
- The energy consumption of the grinding process is large. During grinding, due to the small chip thickness, high cutting speed and serious slip friction, the deformation of the machined surface and the chip is large. This characteristic means that in terms of power, although the amount of wood grinding per minute is not large, the amount of wood cut by each cutting edge is very small, and the number of chips cut per unit time is large, so grinding A chip of a certain mass consumes much more energy than it takes to mill a chip of the same mass the sandpaper for belt sander is a ring-shaped coated abrasive tool that uses a binder to adhere the abrasive to the substrate and is used for sanding belt grinding.
The belt sander paper are divided into cloth sanding belts, paper sanding belts and cloth-paper composite matrix sanding belts according to the different substrates used. – The base body of the general belt sanding belts has joints, and there are also jointless cloth sanding belts specially woven into annular abrasive sanding belt. The emergence of multi-joint sanding belt and spiral joint sanding belt makes the width of sanding belt break through the limitation of cloth and paper width. The maximum width has exceeded 4 meters, which can realize one-time processing of large area. The multi-joint 3/4 x 12 inch sanding belts can be butted or overlapped, and polyester film is generally used as the substrate when docking. The spiral joint sand belt has two layers, generally paper is used as the backing layer, the two layers are butted, and the seams of each layer are staggered. The belt sander belts 3×18 has a large width, light weight and softness. It has become an important abrasive tool for large area, complex profile and high-efficiency processing. It is widely used in the grinding and polishing of stainless steel plates and plywood, as well as the grinding of jet engine and steam turbine blades.
