Hardness and Selection of Flap Wheels

The flap wheels have different material and hardness. Naturally, the effect is different.

1. Hardness refers to the difficulty of abrasive particles falling off on sandpaper grinding wheel surface under the action of grinding force. The hardness of the product is soft, indicating that the abrasive particles of the product are easy to fall off. Hardness of the product means that the abrasive particles are difficult to fall off.

2. Flap wheel hardness and abrasive hardness are two different concepts. The same kind of abrasive can be made into different hardness, which mainly depends on the properties, quantity of binder and its manufacturing process.

3. The remarkable difference between grinding and cutting is that it has "self-sharpening". Choosing the hardness of grinding wheel is actually choosing its self-sharpening. It is hoped that the sharp abrasives won't fall off too early, won't don't fall off until they are worn bluntly either.

4. The general principle of grinding wheel hardness selection is: when processing soft metals, in order to prevent abrasives from falling off prematurely, the hard type should be chosen. When processing hard metals, in order to make the blunt abrasive peel off in time, so as to expose new abrasive particles with sharp edges and corners (i.e. self-sharpening), soft products are selected.

5. The former is because the working abrasive wear of the grinding wheel is very slow in grinding soft materials and does not need to be separated too early; the latter is because the working abrasive wear of the grinding wheel is faster in grinding hard materials and needs faster updating. In order to ensure grinding accuracy and roughness, slightly harder grinding should be selected.

6. When the thermal conductivity of the workpiece material is poor and it is prone to burn and crack (such as grinding hard alloy etc.), the softer one should be chosen.