The hardness and grits knowledges for grinder abrasive discs

When grinding with coarse-grain grinding wheel, the production efficiency is high, but the workpiece surface is rough.  When grinding with fine grain grinding wheel, the workpiece surface roughness is better, but the productivity is lower.  On the premise of meeting the roughness requirements, coarse-grained grinding wheels should be selected as far as possible to ensure higher grinding efficiency.

Generally, coarse grain grinding wheel is used for coarse grinding, and fine grain grinding wheel is used for fine grinding.  When the contact area between grinding wheel and workpiece is large, the grinding wheel with coarser grain size should be selected.  For example, when grinding the same plane, the grain size selected by the end grinding of the grinding wheel is coarser than that by the peripheral grinding of the grinding wheel.  The applicable scope of grinding wheels with different particle sizes.

The choice of hardness depends mainly on the workpiece material being ground, grinding efficiency and machined surface quality.  Hardness refers to the degree of difficulty for grinding wheel grain to fall off under the action of external force. In order to adapt to the requirements of grinding of different workpiece materials, grinding wheel manufacturing is divided into different hardness grades.

Grinding wheel selected hard, blunt abrasive particles are not easy to fall off, grinding wheel is easy to plug, grinding heat increases, the workpiece is easy to burn, grinding efficiency is low, affecting the surface quality of the workpiece;  If the grinding wheel is too soft, the grinding grain will fall off when it is still sharp, which increases the grinding wheel loss, easily loses the correct geometry, and affects the accuracy of the workpiece.

Therefore, the selection of grinding wheel hardness should be appropriate, and should be considered comprehensively according to the contact area between grinding wheel and workpiece, workpiece shape, grinding mode, cooling mode, grinding wheel bond type and other factors.  The following grinding wheel hardness selection principles are for reference: A.  Hard  grinding wheels should be selected when grinding soft materials, and soft grinding wheels should be selected when grinding hard materials

Post time: Apr-29-2022