钢筋横肋末端间隙超出标准的原因分析及优化改进

分析了带肋钢筋横肋末端间隙超出标准的原因,包括加工成品孔型的刀具磨损量太大、轧钢时的轧槽磨损严重等。通过定期更换成品孔型加工刀具、改变轧槽横肋末端的加工方法和及时更换轧槽,使成品带肋钢筋横肋末端间隙尺寸满足热轧带肋钢筋标准GB/T1499.2-2018的要求。     

热轧月牙肋钢筋横肋加工的设计及分析

本文分析了热轧月牙肋钢筋成品孔横肋槽的加工原理，介绍用普通铣床改造成铣月牙肋横肋槽专用机床，及如何加工轧辊横肋糟的设计方法，以保证轧辊孔型轧出符合国家标准GB1499－91《热轧混凝土用带肋钢筋》的月牙肋钢筋。     

一种计算热轧钢筋成品辊轧制时前滑值的经验公式

通常热轧带肋钢筋轧制时,因成品需充填横肋和纵肋,使之金属流动过程复杂,造成影响前滑值因素增多,故计算其前滑值困难。充分利用钢筋成品轧制时,前滑值便于实测的有利条件,在对大量数据进行统计分析的基础上,归纳总结出一种经验公式,以便计算出棒材机组钢筋成品轧辊轧槽的横肋个数,从而准确确定出钢筋横肋间距,使得钢筋横断面金属量得到合理分配,促进了钢筋生产质量的稳定。     

高线精轧机辊缝补偿技术创新与实践

分析了宣钢公司高线厂生产事故频发、作业率低、成品尺寸超差、螺纹钢横肋不够的原因,认为精轧机内各架次轧槽磨损不均是主要原因。以解决精轧机烧导卫堆钢事故为突破口,修订了精轧机辊缝补偿标准,调整优化了精轧机换辊次序,减少日检修换辊架次,大幅压缩日检修时间,并辅以主控台速度设定与预加张力优化、活套系统改造。优化后,作业率及成品质量明显提高,达到了同行业领先水平。     

数控轧辊铣床的设计与应用

在分析螺纹钢轧辊月牙槽的空间几何特征与成形原理之后,设计研制成功一种全新的数控螺纹钢轧辊槽形铣床。它突破了传统的加工方法,效率高、加工精度高、质量稳定,具备铣槽、刻字、刻痕等多种功能。     

离心复合高速钢轧辊高效加工方法

主要介绍离心复合高速钢轧辊轧槽加工设备选型、刀具选择及其装夹方法,轧槽加工的车削加工工艺及铣削加工工艺。     

精轧螺纹钢筋关键轧制技术的开发和应用

介绍了轧制精轧螺纹钢筋外形实现的难点和关键技术,以及横肋间距、成品辊径、横肋倾角的计算方法.为了保证横肋的精确对正,发明了一种圆周方向可精确调整的连接轴.目前,承钢公司成功开发的左右旋φ20 ～ 32 mm精轧螺纹钢筋,满足国家标准和用户要求,扩大了承钢公司的产品类型.     

X63W铣床的改造

莱钢锻压力对Ｘ６３Ｗ铣床进行改造,重新设计齿轮箱,改造传动轴和承轴,用于加工螺纹钢成品辊横筋槽,满足了车间对螺纹成品辊的需求。     

Φ12mm热轧带肋钢筋四线切分轧制工艺存在问题及解决措施

针对Φ12 mm热轧带肋钢筋四线切分生产工艺中精轧机组导板粘钢、切分架次出口堆钢、成品架次出口堆钢、轧槽磨损严重等问题,通过改进轧辊材质、控制轧辊轴向串动及弹跳等措施,实现了Φ12mm热轧带肋钢筋四线切分轧制的稳产、高产。     

昆玉钢铁棒材生产线工艺技术改进

文章介绍了昆玉钢铁棒材生产线进行的工艺优化改进:针对生产工艺存在的横肋充不满,横肋高度低,钢材负差率低问题,优化了孔型设计;针对生产大规格钢材弯曲试验裂纹问题,改变横肋与钢筋轴线的夹角β,改变辊槽横肋根部加工方法,以及调整开轧温度、控轧控冷温度等措施,改善了钢材的冷弯性能;通过优化穿水管的内腔尺寸,增大水压,优化冷却工艺等措施,解决了多切分生产时钢材性能线差大、力学性能不稳定的问题。     

Behavior of Transversal Crack on Slab Corner During V-H Rolling Process

The behavior of transversal cracks on the surface of the slab corner during vertical and horizontal （V-H） rolling process with flat vertical roll and groove vertical roll was simulated by explicit dynamic finite element method. The closure and growth of crack and the contact pressure on surfaces of the crack in contacting zone between slab and roll during rolling process were analyzed. The results showed that during vertical rolling process, when the groove vertical roll is used, the maximum contact pressure on surfaces of the crack is 115 MPa, and the closure of crack is stable when the flat vertical roll is used, the maximum contact pressure on surfaces of the crack is 70 MPa, and it fluctuates greatly. During horizontal rolling process, when groove vertical roll is used, the contact pressure becomes zero which may accelerate the growth of crack when flat vertical roll is used, there is still contact pressure. The cal culated results are in good agreement with the results of test.     

激光特种合金化技术在棒材轧辊中的应用

针对激光特种合金化技术在棒材轧辊应用中存在的问题,通过采取增加表面粗糙度和表面堆焊及刻痕、不同工作面采用不同加工工艺、改进轧辊冷却水装置、优化轧槽修复量及单槽轧制量等措施,轧辊的使用寿命提高1倍以上,轧辊消耗降低10%。     

不锈钢/碳钢耐蚀海水带肋钢筋轧制复合工艺

摘要：海洋工程用带肋钢筋要求有耐氯离子腐蚀能力，但选用双相不锈钢生产成本过高，不锈钢 碳钢轧制复合钢筋则可兼顾耐蚀性和低成本。覆层采用2205不锈钢，基材为低合金钢20MnSi，用有限元方法模拟钢筋的热轧复合过程，分析轧制过程尤其是成品孔中轧件的变形规律。有限元仿真发现，矩形组合坯料无孔型轧制时，其角部复合困难，而成品孔轧制时，钢筋横肋根部的应变最大，覆层在此位置减薄显著，应选择合适的复合坯覆层厚度。在实验室采用焊接、真空处理和热轧方法制备了直径为16mm的复合钢筋，屈服强度为485MPa，抗拉强度为701MPa，断后伸长率约为37.1%，复合界面剪切强度为317.5MPa。复合钢筋呈良好的冶金结合，Fe和Cr的扩散层厚度约为40μm。该工艺生产的复合带肋钢筋成本较不锈钢降低50%以上。     

Analysis of Crack Tip Stress of Transversal Crack on Slab Corner During Vertical-Horizontal Rolling Process by FEM

Behavior of transversal crack notched on slab corner during vertical-horizontal rolling process was simulated by FEM. The crack tip stress in the whole rolling process was obtained. Influences of the friction coefficient, the initial crack size, the edger roll profile, and the groove fillet radii of grooved edger roll on crack tip stress were analyzed. For vertical rolling, the tension stress appears at crack tip near the slab top surface and the compression stress appears at crack tip near the slab side surface for the flat edger roll; however, the compression stress appears at crack tip near the slab top surface and the tension stress appears at crack tip near the slab side surface in the exit stage for the grooved edger roll. For horizontal rolling, the tension stress appears at crack tip just at the exit stage for the flat edger roll, and the tension stress appears in whole rolling stage; the tension stress value near the slab side surface is much larger than that near the slab top surface for the grooved edger roll.     

高线粗中轧轧辊轧槽磨损规律浅析

轧辊槽面状况直接影响高速线材盘条表面质量,对粗中轧不同机架轧辊孔型磨损进行了大量测量,结果显示,无论是椭圆孔型还是圆孔型,孔型磨损都呈现极大不均匀性,槽底磨损量最大;沿轧制方向,磨损量逐渐增加,且椭圆孔型磨损量增加幅度高于圆孔型;单机架磨损量随吨位呈正相关关系。这些基本规律,有助于轧机操作人员适时地进行辊缝调整,更容易地控制料形。     

Mechanism generating deviations in the rolling load and strip camber on the plate rolling mill

Both the support force inequality on both ends of the roll and the camber are common drawbacks, those were caused by the static indeterminacy of structure design, backlash and offset setting selection on the plate rolling mill. There are many technical literatures for analysing the reasons for generating of the strip camber, which are mainly the external factor analysis, however, the internal cause of the mill roll system is ignored. The negative effects of offset distance setting and side clearances of about 1?mm between the chocks and side surface of the housing window should be considered on the plate rolling mill. In reality, the primary cause of this deviation and the strip camber lies in the interaction between offset distance setting and cross of the rolls. The greater the offset setting value of the plate rolling mill, the greater the generation probability of pressure difference and the camber. Some measures, involving eliminating offset distance setting, effectively controlling the side clearances between chocks and housing window, eliminating initial cross and dynamic cross phenomenon, should be taken to maintain the rolls parallel and to prevent radically the support force inequality on both ends of the roll and strip camber.     

CVC轧机辊型设计原理和控制模型的探讨

CVC技术对于板带的断面形状及板形的控制是非常有效的手段,而开发这一技术的关键软件是CVC辊型的设计原理及轧机的控制模型。 本文阐述了辊型的设计原理,指出CVC的S形辊型曲线由以下三部分构成,1.标准轧制状态下承载辊型的三次基本曲线;2.补偿标准轧制状态下轧辊变形的二次曲线;3.补偿基本曲线锥度的三次曲线。根据这一原理推出轧辊的凸度值是带钢宽度和横移距离的函数。 另外,还以轧辊的弹性变形理论出发导出了带钢凸度、宽度及轧制压力之间的关系。基于导出的关系,便可进行轧辊横移距离的设定,以补偿由轧件宽度及轧制压力的扰动所引起的轧件凸度变化,从而达到控制效果。     

Analysis of roll-stamping process for rib grooves of ultra-high-strength beam parts

Roll-stamping technology,a new process with both roll-forming and stamping characteristics,is suitable for manufacturing ultra-high-strength beam parts,especially variable cross-section beam parts.The rib groove is a local shape often used in automotive parts for positioning,avoidance,and stiffness strengthening on longitudinal and stiffening beams.In this study,two typical rib grooves,the flat-and round-bottom rib grooves,were selected to investigate the characteristics of the roll-stamping process of rib grooves.Using the ABAQUS software platform,a simulation analysis model of rib-groove roll stamping was established and different size rib grooves produced by the roll-stamping process were compared and analyzed.The results show that when the fillet radius of the rib groove increases,the maximum Mises stress,the maximum strain,and the maximum thinning rate decrease.For roll stamping,the minimum safe fillet radii of the two types of rib grooves are 8 and 4 mm,respectively.     

4线切分轧制技术分析

详细介绍BSW公司的4线切分轧制的孔型系统、轧辊结构、导卫结构、轧制控制以及对轧机的要求,展望了该技术的发展空间。