Packaging steel strip rolling crack of causes and solutions

( 1) Defect features: the packaging steel strip of scratch, scratch, traces of metal in the rolling tear. In local with a transverse crack or metal fall off the hole. Scratch rolling crack is caused by the short follow-up or continuous strip, rolling crack is caused by the short article scraped tadpole shape, cat's paw of single or multiple rows distribution ( 2) Cause (1) packaging steel strip material original clean cut. (2) the packaging steel strip is in the process of pickling or shear pien bump scratch. (3) mill guide embedded iron wrapped steel with scratches. (4) don't tight the pickling steel coils or rolling roll down the bad operation, when the tension of rolling, volume layer occur between dislocation and scratch the surface. ( 3) To prevent and eliminate method (1) prevent raw materials packaging steel strip surface scratches. (2) in a timely manner to eliminate scratches the surface of the steel strip packing various hidden dangers. (3) check guide, found that people who are iron embedded timely replacement. (4) controlling packaging steel strip coiling tension, tightly rolled steel coils. (5) roll down the operation to be firm, shall not be reversed. ( 4) Check to determine (1) check with the naked eye. (2) high quality plate standards specified in the group I board there is no cracking. 2 group board opposite is allowed within the scope of the tolerance range is not greater than the minimum thickness of small cracking. 10 groups both sides plate allows within the scope of the half thickness tolerance is not greater than the minimum thickness within the scope of the small ripping, reverse side is allowed within the scope of the tolerance is not greater than the minimum thickness within the scope of the small cracking. Ordinary plate without rules, depending on the specific situation, ripping the judgment of the method is: the serious cracking appeared a fissure or metal meat pits are given for the trash. Degree of light, the less number of cracking, can according to the targets to be tried for qualified products. Only marks without cracks or meat according to the provisions of national standard quality plate to plate for 2 group. A slight tear or meat can be jailed for three groups as stipulated in the national standard of high quality plate or gb ordinary version of the product.