2. Machines factors

Glass tempering process includes four steps, which are cutting, grinding, washing & drying, and tempering. Scratches are mainly caused by the former three steps.  

There are two kinds of cutting ways, which are cutting manually and cutting automatically. No matter which way is chosen, the cutting table and splitting table must be kept clean. In order to protect glass from scratch, softer carpets always are used as surface covers of tables. However, carpets are most likely to hide the glass chips, and cause long, deep scratches and a direct result of waste. 

2.2 Grinding

There are two kinds of grinding ways, which are rough grinding and fine grinding. Diamond edge grinding machine is used to grind glass roughly. Glass is supported by caster wheels, and near to the high-speed rotating diamond polishing wheel manually. After using for a period of time, un-ground glass edges would make supporting wheels rough and broken, then glass chips would hide in rough wheels, cause scratches on glass. Therefore, roughed supporting wheels must be replaced or cleaned on time. 

If the cooling water of straight-line edging machine can't be kept clean, glass chips would leave on the transmission plate through the spray tube, and touch glass surface. Transmission plate is flexible, so that glass would slip with it relatively, and cause long-point like scratches.