The principle of lapping is simple and based on the grinding power of a free grain in an emulsion. A lapping plate on which a lapping emulsion has been applied moves under the workpiece surface.Due to the movement of the lapping plate in relation to the workpiece, you slowly remove material.
Lapping can be used to obtain a specific surface roughness; it is also used to obtain very accurate surfaces, usually very flat surfaces.
Lapping plate is a very important part of lapping machine.When the lapping machine start lapping plate move and make a surface flate or smooth.Most of lapping palte is make using cast iron.