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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。 相似文献
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文章介绍了棒线材生产线采用切分轧制工艺,热轧带肋钢筋横肋顶端出现平面缺陷问题,该缺陷导致成品热轧带肋钢筋横肋高度不达国标.通过从切分轧制工艺孔型系统、轧制参数、工艺备件、调整方法等多方面入手,解决了切分轧制热轧带肋钢筋横肋顶端出现平面现象,从而提升了切分轧制热轧带肋钢筋成品质量,确保了热轧带肋钢筋产品符合国家标准. 相似文献
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利用3D软件,对热轧带肋钢筋底圆、横肋、纵肋进行了重量计算,各部分对负公差的影响大小依次为内径—横肋—纵肋,内径尺寸的设计是控制负公差的重点,对孔型设计、加工提出了原则性建议:设计较小的内径,适当加深横肋,减小螺旋角。 相似文献
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带肋钢筋实行负偏差轧制,不仅能给企业带来一定的效益,而且能降低钢筋使用部门的工程建筑费用。一般提高钢筋负偏差率的办法是减小钢筋的内径,但减小钢筋的内径会明显降低钢筋的强度,承载能力降低,计算钢筋强度用截面面积GB1499—1998标准规定采用公称横截面面积,因此钢筋的强度会降低,甚至会造成钢筋的强度不合格。 相似文献
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本文阐明了对热轧带肋钢筋(简称带肋钢筋)横肋高度符合GB/1499—1998标准要求的看法,对在工艺条件不变的情况下生产较大规格带肋钢筋横肋高度出格的原因进行了分析,指出加强过程控制是保证产品质量的重要环节。 相似文献
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详细介绍了热轧带肋钢筋月牙型轧槽切削中 ,横肋斜角 ,铣刀回转半径 ,横肋槽数等参数的选择及计算方法。 相似文献
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对重量偏差数据的统计分析表明,马钢生产的热轧带肋钢筋重量偏差富余量较大,而锯切前后,所测量的钢筋长度对重量偏差影响很小。本文提出可以对80%来样,通过直接称重量和测量长度来计算重量偏差,而对20%的来样,进行锯切加工后,测量钢筋的长度,计算重量偏差,用做数据的比对。 相似文献
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四辊平整机组复杂浪形控制技术 总被引:2,自引:0,他引:2
针对平整机组因压下量小、变形热与摩擦热少、轧辊热凸度不大而无法采用精细冷却的方式控制中双组合浪、单肋浪、多肋浪、中肋组合浪、边肋组合浪等复杂浪形缺陷的问题,以四辊平整机组为研究对象,提出了一套采用非对称式结构来替代对称性结构,将板形控制手段从传统的对称弯辊(对称窜辊)、倾辊等二维增加到左弯辊、右弯辊、上窜辊、下窜辊以及倾辊等五维的板形控制思想,并在此基础上以实际板形与目标板形的差值最小为目标建立了一套适合于四辊平整机组的复杂浪形控制技术,通过左弯辊、右弯辊、上窜辊、下窜辊以及倾辊等板形控制参数的优化设定,有效解决了四辊平整机组复杂浪形缺陷的控制问题,弥补了平整机组因无法采用精细冷却而带来的板形控制先天性不足问题,为现场平整机组板形精细控制提供了一套新方法,具有进一步推广使用的价值。 相似文献
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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. 相似文献
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Tensile strains ahead of entry into the roll gap were analysed using the finite element method and compared with results of the analytical approach developed by Pawelski [1]. The longitudinal tensile strains in the stock surface ahead of contact with the roll produced by frictional contact with the roll were calculated for the different roll gap aspect ratios, ho/L = 0.1,…1 and Coulombic friction coefficient 0.1,…0.5. The results have been analysed in terms of oxide failure resulting from this kind of deformation and compared with predictions using the advanced oxide scale model. A simple formula has been developed to evaluate the longitudinal strain component at entry into the roll gap for a given friction coefficient and aspect ratio. It was related to cracking of the oxide scale in tension at this area. Prediction of the scale behaviour at this area is a key to understanding the friction and heat transfer phenomena taking place at the roll/stock interface. It is also important for optimisation of descaling operations. 相似文献
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对液压胀形轧辊(即国外的VC轧辊)辊套热装后的弹性变形进行了有限元分析,给出了确定油槽最小深度的计算公式。本文的有限元计算结果与实验结果吻合,某些结论可为液压胀形轧辊的结构设计提供理论依据。 相似文献
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Local elastic roll flattening in direction of the roll axis in flat rolling is one of the important displacement components related to the roll gap shape. Up to now some classical formulae to solve roll flattening have been proposed. These formulae were derived from the elastic half space theory or the 2-dimensional contact theory. On calculating the flattening of the back-up roll they may result in a great deviation. In the present effort a comparison was made between the flattening results obtained by a 3-dimensional finite element method and by a classical formula. The relation between the deviation and the back-up roll geometry was also examined and therefore the classical formula was modified. Calculated results indicate that the modified formula can more accurately predict the back-up roll flattening. 相似文献
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