粗轧狗骨失宽的控制

CONTROL OF ROUGH ROLLING DOG BONE SHAPE WIDTH LOSS

轧件宽度控制作为粗轧过程控制的一个重要组成部分,其控制精度已成为衡量带钢生产质量的重要指标之一。对于厚宽比较大的轧件,经立辊轧制后轧件的宽度被压缩,断面形成狗骨形,从而造成头尾失宽,导致生产造成额外的切损。本文主要研究了狗骨的形成机理,分析了影响宽度断面形成的主要因素为立辊侧压量、立辊直径、轧件宽度和厚度等,且立辊侧压量、直径越大,狗骨高度和失宽量越大;轧件来料尺寸越大,狗骨高度和失宽量越大。并以柳钢热轧厂2032生产线为例,通过调整各道次立辊侧压量,在不起拱的前提下减小首道次增大末道次侧压量,提高头部宽度均匀性;根据实时曲线调整头尾短行程的设置幅度,减小头尾失宽程度;更改立辊辊形减小狗骨高度等方式,优化了狗骨失宽现象。

As an important part of roughing process control, the control accuracy of rolled width control has become one of the important indicators to measure the quality of strip production. For rolled parts with a large thickness to width ratio, the width of the rolled parts is compressed after rolling by vertical rolls, and the section forms a dog bone shape, resulting in loss of width of the head and tail, resulting in additional cutting damage caused by production. In this paper, the formation mechanism of dog bone is mainly studied, and the main factors affecting the formation of width section are the side pressure of the vertical roll, the diameter of the vertical roll, the width and thickness of the rolled parts, etc., and the larger the side pressure and diameter of the vertical roll, the greater the height and width loss of the dog bone. The larger the incoming size of the rolled part, the greater the height and width loss of the dog bone. Taking the 2032 production line of Liugang hot rolling mill as an example, by adjusting the side pressure of each pass vertical roll, the first pass is reduced and the last pass is increased under the premise of no arch, and the uniformity of the head width is improved. Adjust the setting amplitude of the short stroke of the head and tail according to the real-time curve to reduce the width loss of the head and tail;The shape of the vertical roller was changed to reduce the height of the dog bone, and the phenomenon of dog bone width loss was optimized.