Packaging steel strip manufacturer: what are the quality requirements for hot rolled strip with the slab?

Packaging steel strip manufacturer: what are the quality requirements for hot rolled strip with the slab? A: for hot rolled strip with the slab quality requirements have the following four aspects: ( 1) Chemical composition should be accord with the requirement of steel grade standard accordingly. ( 2) Size deviation. Among them: 1) Thickness deviation for & plusmn; 5. 0mm。 Excessive negative difference can reduce furnace production, increase the heat energy consumption. Too much is bad to increase from the section of the slab temperature, easy to induce the failure of rolling, thin strip tail control precision of the finishing temperature decrease; When rolling roll diameter limit of material, can cause difficult discharge volume assignments. 2) The width deviation for & plusmn; 10. 0mm。 Excessive negative difference will cause the furnace charging slab gap increases, high temperature and long time heating of the slab, Angle are prone to excessive heat or burn; Reduce heating furnace production; Increase the heat energy consumption. Too much is bad easily induced VSB rolling mill fault, reduce the width of the strip steel precision. 3) The length of the deviation for & plusmn; 30. 0. Excessive deviation affect the amount of cantilever slab beam inside the furnace, bruised beam on refractory wound; When the mill was empty too much is bad will influence of tracking for R2 accidentally judgment. ( 3) The requirement of the slab shape. Bending and rocker: up and down a list of materials for 50 mm; Two column material is 25 mm. Up and down too much curved slab furnace charging positioning; Prone to wandering in the slab in the furnace; Curved slab under, bruised beam in furnace refractories; Affect the bite R1 rolling mill. By the large bending affect the clearance of the slab in the furnace, Has the influence on board when the strip; Affect the side guide is set or scraping the broken edge; Rocker induction of strip steel, steel coil produce tower; Affect the quality of cut sapwood trimming or the width of the finished product sheet. ( 4) The surface quality requirement. The slab surface must not have crack, corner crack, cracking, scarring and inclusion; Allow a depth not greater than 2. 0 mm porosity, crack, scratch, knocking the pit and pitting, and depth is not greater than 4. The vibration of the 0 mm water lines. Slab cutting face, can not have shrinkage cracks and visible. The slab side not greater than is allowed in the indentation. Surface defects of slab side to allow cleaning, cleaning the depth shall not be greater than 100 mm.