The Importance of Slitting Rolling Technology

Whether the rolled piece can be cut or not depends on the thickness of the joint and the relative reduction, as well as the pass shape and dimensions of the slitting rolling. In the pass design of the slitting process, the design of the pre-slitting and slitting hole is particularly important, followed by the vertical box pass. The pass design of these passes is related to the success of slitting rolling.

The pre-slit hole is a transition hole to ensure that the hole can be cut smoothly. The purpose of the pre-slit hole is to reduce the non-uniformity of the hole, make the wedge complete the reduction and positioning of the opposite rolling piece, and accurately distribute the section area of the rolling piece, reduce the burden of the hole as much as possible, so as to improve the stability and uniformity of the cutting. The design shall have enough reduction, the elongation coefficient shall be 1.3-1.4, the spreading coefficient shall be about 0.6, and the height of the connecting belt shall be 0.45-0.48 times of the pass height.  

The slitting hole is basically formed by the connection of the double round pass and the slitting wedge. The function of the slitting pass is that the slitting wedge continues to press down the middle part of the pre slitting rolled piece, rolling out the rolled piece with the same shape as the pass, so as to make the thickness of the connecting belt meet the needs of splitting multiple parallel rolled pieces. In the process of slitting rolling, because of the role of slitting wedge, the restriction of sidewall without pass on both sides of the rolling piece in the slitting pass and the complex section shape of the rolling piece, the change rule of the rolling piece is different from that of the conventional rolling. Its main features are as follows. Serious uneven deformation. The reduction deformation of the wedge is often larger than that of other parts.  

The segmentation deformation is no extension or small extension deformation. When splitting the rolled piece in the slitting hole, the reduction at the bottom of the groove is small, while that at the slitting wedge is large, and the metal is affected by the slitting wedge, and the horizontal component force pointing to the spreading direction is large, which belongs to forced spreading deformation, so the overall extension is small and the spreading is large.  

When multiple pieces are cut, the cross-section of the middle and the side of the piece is different, the two sides of the piece are wide, and the extension is small; the size of the head and the middle of the piece is also different, and the head and the tail have wide space. The wedge angle of the cutting hole shall be reasonable. If it is too small, the clamping force of the cutting wheel will be too large, and the load of the cutting wheel will be increased, generally at 60 °- 65 °; if the angle of the wedge tip is 1-1.5mm, it is better, and if it is too high, the roll will wear and even lose flesh; the thickness of the connecting belt shall be close to the roll gap, 1-2mm is the best; the elongation coefficient shall be 1.08-1.15, and a certain space shall be reserved.