1. The surface of the plate shall be clean with five greasy spots, and no cracks or oxidized sundries are allowed.

2. The surface of the plate is allowed to have defects such as indentation, scratch, roll indentation, etc., but its depth shall not exceed the allowable negative deviation of the plate, and the minimum thickness shall be ensured.

3. The process aluminum clad thick plate is allowed to have the falling part of the cladding layer and the bubble of the cladding layer.

4. The defects within the range of thickness difference are allowed to be removed on the plate surface.