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立辊孔型内倒角半径对轧件变形的影响 总被引:3,自引:0,他引:3
采用显式动力学有限元方法,对立辊孔型内倒角半径R为30、50、80、110 mm 4种情况下多道次立-平轧制过程进行了模拟.分析了立辊孔型内倒角半径对轧件切头尾量、轧件稳定段轧件边部变形程度的影响.研究发现:既定条件下,第1道次立-平轧制过程中,随内倒角半径的减小头尾不均匀区域长度减少,第2、3道次立-平轧制过程中,随内倒角半径的增加,头尾不均匀变形区域长度道次增加量减少;对比采用R为30 mm的孔型立辊和R为110 mm的孔型立辊轧后轧件的头尾不均匀长度,前者比后者少5.03%;轧件稳定段轧件变形程度随着孔型立辊内倒角半径的增加而减少. 相似文献
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YU Hai-liang LIU Xiang-hua LI Chang-sheng Y. Kusaba 《钢铁研究学报(英文版)》2006,13(6):31-37
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. 相似文献
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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. 相似文献
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论述了钢筋肋面积的计算方法。结合月牙肋钢筋典型的成品辊加工曲线,提出了另一种新的肋面积计算方法。用新方法探讨了孔型设计、轧辊加工及工艺控制等关键环节对肋面积的影响。此外,对本计算方法与Simpson方法的计算结果进行了比较。 相似文献
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ListofSymbol E———Elasticmodulusofrollsleeve ; d———Diameterofrollmandrel; l———Lengthofbulgingrollsleeveoroilgroove ; ns———Safetyfactorofmaterial; p———Hydraulicpressureinrollsleeve ; r1 ———Innerradiusofrollsleeve ; r2 ———Outerradiusofrollsleeve ; ymax———Maximumbulgingofrollsleeve ; σs———Yieldstrengthofrollsleeve ; μ———Poisson′scoefficientofrollsleeve ; Δ———Thicknessofrollsleeve ; Δmin———Minimumthicknessofrollsleeve … 相似文献
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斜轧钢球孔型设计新方法 总被引:2,自引:0,他引:2
首次提出将螺旋孔型斜轧钢球轧辊的成型区型腔分为两部分进行研究。在型腔封闭部分,设计时仅需考虑满足设计第二原则,第一原则自然满足。在型腔未封闭部分,设计时仅需考虑满足设计第一原则,第二原则不必考虑。从理论上分析,这样设计的孔型有利于型腔中金属的合理流向。轧制实践表明,采用这种孔型能轧制出比前苏联、美国两种孔型更高质量的钢球。 相似文献
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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。 相似文献
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主要研究圆孔型作为中间孔轧制方坯时的工艺变形特点,通过圆坯在菱形孔以及菱形轧件在后续方孔中变形规律的仿真分析,并对比方坯在菱形孔的变形特征,认为通过合适的轧制压下分配,利用圆孔作为中间孔轧制方坯在工艺上完全可行,完全可以轧制出满足尺寸要求的方坯成品。这种工艺配置不仅可以有效提高多坯型轧制时的孔型共用性,减少轧辊待机量,而且与常规菱方孔型轧制方坯的工艺相比,新工艺在改善成品角部质量,减少轧辊应力集中,减少轧件鱼尾变形量等方面具有明显的效果。 相似文献
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热成型钢及热成型技术 总被引:2,自引:0,他引:2
对热成型钢的成分设计、热成型工艺过程以及表面氧化的处理进行了论述。热成型工艺可以通过直接热成型或者间接热成型实现;热成型钢都是含硼钢,硼能抑制成型过程中铁素体形核;通过锰、铬和钼等提高淬透性防止珠光体形成;一般热成型钢中含有0.2%左右的碳。热成型钢可通过喷丸的方法消除表面氧化层或者镀层技术保护其表面不受氧化。 相似文献
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针对鞍钢中板厂四辊可逆机工作辊的特点,试制了离心铸造工作辊代替常规大冲洗法生产的高合金工作辊,结果表明,离心铸造工作辊具有较高的综合力学性能,辊身硬度的均匀,减少了轧制过程中工作辊剥落的现象,使用寿命比常规辊提高2倍以上。 相似文献
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水钢第一轧钢厂在高速线材轧机上生产铌微合金化HRB400热轧带肋螺纹钢筋,除成品孔型采用碳化钨螺纹辊环外,其余全部使用原孔型系统,产品力学性能达到了Ⅲ级螺纹钢标准。同时对影响钢筋力学性能、金相组织的因素进行了分析和探讨。 相似文献
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冲压成形是金属板材加工异形件的最基本方式。金属材质不同,冲压成形异形件的难易程度不同,主要影响因素是冲压成形性能和冲压成形极限。文章结合铍板材的冲压成形性能和冲压成形极限,对铍板材冲压成形异形件的难易性作了探讨。 相似文献
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Conclusions The rate of hardening the powder mass in rolling in the first groove is determined by the strain and by the angle of inclination of the walls of the groove. The hypothesis of the equality of the perimeters of the powder billet prior to and after rolling has been confirmed for single-pass rolling cylindrical capsules with the powder in various grooves. The maximum compacting of the powder material without overfilling the groove is obtained using the oval groove with the axes ratio higher than 3.Translated from Poroshkovaya Metallurgiya, No. 9(297), pp. 98–100, September, 1987. 相似文献
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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。 相似文献