| 摘要 |
<p>PURPOSE:To improve a product yield based on the accuracy of rolled pipe-wall thickness, by estimating the amount of abrasion of plug diam., from the initial values of plug diameters of several plugs using for rolling and the elongated length of each pipe material due to rolling to correct the set value of screw-down for the next rolling material, in plug mill rolling. CONSTITUTION:A pipe material is rolled by caliber rollers 2 and a plug 4. The plugs 4 are prepared plurally for exchanging the plug at every pass of rolling automatically by a plug exchanger 6. In this case, the weight and actually elongated length of the preceding rolled pipe material are measured by a measuring device 12 to be inputted to a computer 11. The deviation between said measured value and the weight of pipe material measured by a pipe weigher 13, and the deviation in the length of pipe material 1 between the actually measured elongation of pipe and the standard value, are obtained, respectively, then an actual plug diam. is computed from the standard sectional area of the pipe material after rolling, and from the standard plug diam. set from a plug diam. setting machine 10. The difference between said computed dia. and the initial value of the dia. of plug 4 to be used is inputted to a screw-down positioning device 8 to correct the rolling reduction with the aid of reduction screws 3 by controlling a screw-down motor 7.</p> |
