Solutions to the Cold Buckling Fault Caused by the Speed Reduction of High Temperature Annealing Furnace

1. The occurrence of cold gourd curling:
In the actual production process of high-temperature annealing furnaces, if it is necessary to reduce the operating speed of the production line, if the power of the fan in the fast cooling section cannot be reduced in time with the decrease of the strip speed, it will also break the stable state of the fast cooling and outdated efficiency sections, and various abnormal situations will occur, among which the more difficult problem is cold bending.
2. The influence of speed on the convexity of furnace rollers:
The operating speed of the production line also has a significant impact on the actual convexity of the furnace rollers in the fast cooling section. When the speed of the production line decreases, if the power of the fan in the fast cooling section does not decrease, the temperature of the gas in the furnace in the fast cooling section will rapidly decrease. Some production lines do not have sealing rollers before and after the fast cooling section, and some production lines do not seal tightly even if they have sealing rollers. The supercooled gas in the fast cooling section furnace will enter the front and rear tensioning roller chambers, causing a decrease in temperature at both ends of the tensioning roller, an increase in temperature difference between the two ends and the middle, and an increase in thermal convexity.
3. The reason for the cold gourd curl:
As mentioned above, when the speed of the production line decreases, the thermal convexity of the tension roller increases, the centering force on the strip steel increases, and the extrusion force from both sides of the strip steel to the middle also increases. Compared with the heating zone, although the temperature of the strip steel is slightly lower and the yield strength is increased, the tension in the rapid cooling zone is higher, making it the higher area in the entire high-temperature annealing furnace. With the increase in product strength, the tension in the fast cooling zone is becoming increasingly high, which often leads to the problem of cold bending.
The standard for easy occurrence of cold bending is also thin and wide strip steel.
The harm of cold curling is also significant, and it is easy to break the belt.
4. Treatment measures for cold gourd starter:
If cold deformation occurs, the operation should also focus on preventing belt breakage. First turn off the burner and fan, then reduce the tension and speed. After the strip steel in the coiling section is passed, close the sealing rollers before and after the fast cooling section, increase the temperature of the furnace roller chamber, and observe the operation of the strip steel in the high-temperature annealing furnace through an industrial television screen at any time. If the strip steel is found to be off track, the handling should be stopped. Due to the complexity of this machining program, some units have standardized and programmed these programs, and designed a one click machining program for cold bending.