There are three main factors that affect the edge quality of the shear strip in the process of sundering the strip by the slitter machine, which are the stacking amount of the upper and lower cutters, the open space on the side and the uniformity of the hardness of the shear strip. That is to say, during the work of the slabbing machine, the side space of the upper and lower disc knives will determine the edge quality of the shearing strip.

From the production experience, it is assumed that the knife gap of the sapping machine equipment is adjusted reasonably. Then, after shearing, the edge of the strip can be divided into four parts: deformation zone, shear zone, tearing zone and burr zone. The shear zone and tear zone are regular and smooth. In general, the shear zone accounts for 20% to 45% of the thickness of the strip, and the thicker the strip, the larger the shear zone is.

The gap size of the shearing knife of the slitting machine equipment will directly affect the burr height. It is generally required that the burr height should not exceed 3% ~ 5% of the thickness of the strip, and generally should not exceed 0.03mm. Suppose that this requirement is exceeded, then the hand inspection will attack feel. Generally, the burr height of the strip after high precision shearing is only less than 1% of the thickness of the strip, which is about several microns.

It is necessary to pay attention to the fact that, if the shear gap of the slabbing machine is too large, the cut strip will be briefly distorted and deformed between the upper and lower knives. In this way, the shear zone becomes smaller and the tear zone becomes larger, leading to the increase of the burr on the edge of the shear strip. On the contrary, if the shear space is too small, there will be more damaged areas, and harmful conflict torque occurs in the damaged area. The damaged end of the uneven strip is worn more heavily on the disk blade, which will make the disk blade blunt quickly, and then shorten the service life of the knife.

In general, the size of the shear knife clearance of the slant is to a large extent determined by the tensile strength and thickness of the shear material. Assuming the material is aluminum strip, then the correct shear knife side gap is 3% to 8% of the thickness of the strip. When the tensile strength and thickness are large, the side gap should be larger.