Influencing factors of roll gap

Because the roll is in direct contact with the rolled piece during rolling, any factor that changes its roll gap will inevitably lead to changes in the size accuracy and appearance of the final product. For plate and strip steel, the change of the roll will inevitably bring about the change of the lateral thickness difference and the shape of the plate. So what are the factors that affect the roll shape as far as the roll itself is concerned? We will understand below.

1) Thermal expansion of the roll. During rolling, the heat of the rolled piece and the heat generated by its deformation and friction will be straightforward.

The heat of the roller will inevitably bring about the thermal expansion of the roller. The thermal expansion caused by the rolling piece and the contacting part is different from other parts of the body. Generally speaking, the thermal expansion of the middle part of the roller is larger than that of the two ends, so that the heat convexity of the roller is generated. Degree, affecting the final shape of the roll

2) Wear of rolls. The friction between the work roll and the rolling piece, the friction between the work roll and the backup roll will cause the rolling

Roller wear. Uneven wear along the length of the roller body will bring about changes in the shape of the roller;

3) Single bending deformation of the roll. It makes the size of the middle part of the roll gap larger than the size of the side part, the middle part of the steel produces convexity, and the side part is thinner. The greater the rolling force, the greater the unisexual bending deformation produced by rolling, the larger the roll diameter, the better the rigidity, and the smaller the unisexual bending deformation of the roll;

4) Rolling elastic flattening. During rolling, due to the rolling force, elastic flattening occurs between the work roll and the support roll between the strip steel and the work roll. What affects the shape of the roll is not the value of the elastic flattening, but the difference in the flattening value along the length of the roll body. For work, if the rolling force is uniform along the width of the strip, the elastic flattening distribution of the work is also uniform. Because the contact length between the work report and the support is greater than the contact length between the work roll and the rolling piece, this leads to The simple flattening is different from each point along the length of the roll body, which ultimately affects the shape of the roll.

5) Original roll shape of rolling. Different original roll shapes will directly affect the shape of the roll. In actual production, we can consider the above influencing factors and adjust the original roll of the roll to meet the needs of production.