毕业论文

打赏
当前位置: 毕业论文 > 外文文献翻译 >

轧钢厂矫直工艺中轧辊柔韧度的影响英文文献和中文翻译

时间:2020-06-02 21:29来源:毕业论文
Abstract. Finite element analyses of rolling processes have been carried out for many years. Most of the simulations focus on deformation of metal plates/sheets without taking into consideration flexibility of rolls and the machine frame. In

Abstract.  Finite element analyses of rolling processes have been carried out for many years. Most of the simulations focus on deformation of metal plates/sheets without taking into consideration flexibility of rolls and the machine frame. In our paper, we present a unique approach to simulation of rolling of thick plates where compliance of rolls and the complete structure of a roll leveler  is  taken  into  account. This  approach makes  it  possible  to  accurately  predict  shape  distortion  of  steel  plates  and  gives valuable, practical information on how to prevent shape defects in a rolled product. In this paper, roll leveling of steel plates after continuous casting, is analyzed. Our approach is universal and can be applied to other types of rolling processes. As a simulation tool, we used a non-linear FEM code.   INTRODUCTION Continuous  casting  is  the  process whereby molten steel is solidified into a steel plate through subsequent cooling  and  rolling  -  Fig.1.  In  recent  years, technological  advances  in  continuous  casting technology  made  possible  to  produce  shapes  that substantially  conforms  to  the  finished  product  (the near-net-shape casting).[1]  FIGURE 1. Continuous Casting Process. There  are  a  few  phenomena,  as  for  example  non-uniform  temperature  distribution  during  solidification or  local  deformations  at  rolling,  which  may  cause geometrical  distortion  of  the  product  shape.  To  deal with these  type of defects, a  roll  leveler  is used at  the last stage of the production process. 50293
Operation  of  the  roll  leveler  requires  very sophisticated  skills  –   not  only  shape  distortion  of plates  coming  into  roll  leveling  has  to  be  taken  into account,  but  also  elastic  deformation  of  rolls  and deformation of leveler structure - frame affect product shape. To  understand  influence  of  various  parameters  of roll leveling process on the final shape of a product we decided  to  use  finite  element  method.   In  our simulation we focused on roll leveling  of thick plates, however  our  simulation  techniques  can  be  applied  to products of any shapes.  Typical  approach  to  analyze  compliance  of  rolls during leveling is to use 3D solid elements to describe roll geometry. We  found  this approach not acceptable –   long  computation  times  for  models  with  huge number  of  degrees  of  freedom made FEM  simulation very  unproductive.  In  this  paper we  present  approach where  rolls  are  described  using  beam  elements,  rigid links  and  contact  segments.  Also  the  complete structure –  frame of a roll leveler is taken into account.  Due  to  the  non-linear  character  of  plastic deformations  in  metal  plates  as  well  as  non-linear character  of  contact  phenomena  between  rolls  and plate we decided to use non-linear FEM code ADINA. Our  simulation models made  possible  to  establish relation  between  residual,  shape  distortion  of  a  thick plate and compliance of rolls and roll leveler structure.  ROLL LEVELING PROCESS In the roll leveling process, as shown in Fig.2, two rows  of  rolls  bend  top  and  bottom  surfaces  of  steel plate  alternatively.  Through  this  process,  localized plastic strain is created just beneath the top and bottom surfaces of the plate. This additional strain compensate initial shape distortion of the plate.  FIGURE 2.  Roll Leveler. Due to a high level of forces necessary to initialize plastic deformation of the plate, deflection of rolls and structure  -  frame  of  a  leveler  becomes  significant,  as shown in Fig.3.  FIGURE 3.  Roll Deformation. That  may  cause  a  non-uniform  initial  strain distribution along the plate width, as shown in Fig.4.   FIGURE 4.  Non-Uniform Strain . To  achieve  required  shape  quality,  deflection  of rolls  has  to  be  compensated  by  a  pre-determined  –  counter-deformation of rolls. This is done usually with an aid of the wedge mechanism, as shown in Fig.5. Production  process  requires  to  adjust  position  of the  wedge  mechanism  frequently,  for  every  different type of plates. 轧钢厂矫直工艺中轧辊柔韧度的影响英文文献和中文翻译:http://www.youerw.com/fanyi/lunwen_53601.html
------分隔线----------------------------
推荐内容