| 摘要 |
PURPOSE:To miniaturize the apparatus and to improve accuracy of product by driving the odd-numbered roll from the upstream making the even-numbered roll non-driving, and rolling under a prescribed conditions to drastically reduce the roll shaft center distance. CONSTITUTION:The odd-numbered rolls 1H, 3H,...(2n-1)H from the upstream are to be driving ones, and the even-numbered rolls 2V, 4V,...2n.V are to be non-driving ones. In this case, to prevent the bulging of rolled stock 1 between the rolls, (the reduction in area of the non-driving rolls)<(the reduction in area of the driving rolls), to avoid the thickness deviation, the relation (sum of thickness rolling reduction at groove bottom of driving roll)=(sum of thickness of rolling reduction at groove bottom of non-driving roll) is established. After the mandrel mill, the extractor 3 for the pipe is disposed to perform the pipe extracting and drawing rolling excellently. By this method, because the center distance between the roll shafts are drastically reduced, the apparatus is miniaturized and the accuracy of the product is improved. |
