The Causes And Solutions of Ceramic Roller Marks on Tempered Glass Made by Glass Tempering Furnace

During the production of tempered glass in a glass tempering furnace, problems such as edge collapse, furnace explosion, pitting, and roller marks may occur due to various reasons. The reasons for its occurrence are also different. Among them, roller marks are a common defect that is prone to occur continuously and cannot be solved in a short period of time. Below, the editor will share with you the reasons and solutions for roller marks on tempered glass in tempering furnaces.

1. Roll marks appear in the middle position of the glass

Reason: This type of roller printing mostly occurs when the furnace is just started or stopped for a long time before opening. The main reason is that the temperature of the ceramic roller conveyor is too high, causing the tempered glass to warp upwards.

Solution: This situation can be solved by turning on sulfur dioxide protective gas or increasing forced convection, or adjusting the temperature difference by lowering the lower temperature of the tempering furnace and increasing the upper temperature, as well as increasing the roller speed. This method can play a mitigating role.

The causes and solutions of ceramic roller marks on tempered glass

During the production of tempered glass in a tempering furnace, problems such as edge collapse, furnace explosion, pitting, and roller marks may occur due to various reasons. The reasons for its occurrence are also different. Among them, roller marks are a common defect that is prone to occur continuously and cannot be solved in a short period of time. Below, the editor will share with you the reasons and solutions for roller marks on tempered glass in tempering furnaces.

2. Roll marks appear in the middle position of the glass

Reason: This type of roller printing mostly occurs when the furnace is just started or stopped for a long time before opening. The main reason is that the temperature of the ceramic roller conveyor is too high, causing the tempered glass to warp upwards.

Solution: This situation can be solved by turning on sulfur dioxide protective gas or increasing forced convection, or adjusting the temperature difference by lowering the lower temperature of the tempering furnace and increasing the upper temperature, as well as increasing the roller speed. This method can play a mitigating role.

3. Roll marks appear at the front end of the glass in the forward direction

Reason: Tempered glass roller marks often occur at the front end of the glass in the forward direction, but not at the back end. There may be two possible reasons for this situation:

3.1. Abnormal photoelectric input: This leads to an error in calculating the length of the glass by photoelectric calculation, resulting in a shortened glass spacing compared to usual. When the furnace is discharged, the roller accelerates but the acceleration of the front glass is not yet completed, and the roller speed does not recover to the tempering furnace injection speed. This causes the front end of the lower glass to come into contact with the high-speed running roller, resulting in roller marks at the front end of the glass.

3.2. The speed of entering the furnace is faster than the main transmission speed: Due to the faster speed of the rollers in the entering section compared to the main speed of the tempering furnace, the distance between the glass entering the tempering furnace is shortened. For example, the distance between the glass at the entrance of the furnace is 300mm, but it may only be 250mm inside the tempering furnace. In this case, it can also cause roller marks to appear at the front end of the glass in the forward direction.

Solution: The problem can be solved by repairing and adjusting the photoelectric system inside the furnace, as well as adjusting the inlet and outlet speeds to make the inlet speed slower than or equal to the outlet speed. Alternatively, increasing the inlet spacing from 300 to 400 can also solve the problem.