1.The glass sheets must be cleaned before tempering to remove the dirt on the surface and the residue left on the glass during the cutting, drilling, and edging process. If the surface of the glass is not cleaned, or it is not sufficiently dried after cleaning, there will be water stains on the surface of the glass. Once the glass sheet is tempered, defects will be formed on the glass surface, and such defects will be difficult to deal with after the tempering process.

2.The glass sheets must be cleaned on a professional glass washing machine to ensure the quality of glass cleaning. Meanwhile, the professional glass cleaning machine generally has a drying process after cleaning the glass, which can make sure a clean and dry surface of the glass sheet before tempering.