HFW焊管排辊成形中线成形段有限元仿真分析

排辊成形已经被广泛的应用于钢管生产,考虑到HFW焊管排辊成形过程十分复杂,涉及到明显的非线性,为了更好地了解板带的排辊成形过程,针对外径508mm焊管排辊成形机组的线成形段建立了大变形弹塑性有限元模形,利用显示动力算法进行了仿真计算,分别得到了线成形段板带的等效塑性应变分布和几何变形,并和实际测量进行比较取得很好的吻合,验证了模拟的准确性。研究表明,排辊成形线成形阶段的较大塑性变形发生在带钢中心和与排辊接触的带钢边缘。     

宝钢HFW石油套管的研发现状和前景

重点对宝钢HFW石油套管的开发现状、已开发的HFW石油套管技术难点和工艺特点进行了阐述,并对宝钢今后HFW石油套管的研发前景进行了讨论.指出宝钢HFW石油套管的发展应突出炼钢＋制管＋管加工及质量一贯制的优势,实现差异化发展;扩展已开发产品的规格和产量,研发大直径厚壁K55、高抗挤以及耐蚀石油套管.     

大直径ERW直缝焊管排辊成型的有限元模拟

采用大型非线性有限元软件Marc对ERW直缝焊管的排辊成型过程进行模拟．获得了成型管坯形状以及各机架截面处和沿板带纵向的等效应力与应变场分布;分析了排辊成型面与管坯的接触状态。为排辊成型焊管机组的孔型设计以及排辊调整提供了理论依据。     

异型管无芯棒辊挤成型过程挤压力公式的建立

异型管无芯棒辊挤成型是一种生产高精度异型管的新技术。该成型方式的特点是力能消耗少、制品表面质量好,且施力形式为推力。该成型是在三向压应力的状态下完成的,变形过程中管子在长度方向上的延伸受到限制,管角部充填性能好,可以获得最小的各边相接处的外半径Ｒ值和更高的加工精度,特别适用于生产大直径厚壁或小型薄壁精密异型管。介绍了使用主应力法建立异型管无芯棒辊挤成型过程挤压力的计算公式。     

成型参数对HFW焊管排辊成型质量的影响

HFW(high frequency welding)焊管的排辊成型过程主要受材料、成型设计、工艺设计方面因素的影响。实际生产中需要知道各影响因素对产品成型质量的影响,为生产工艺的制定提供理论上的参数定性、定量选择依据。基于508 mm直缝焊管的排辊成型过程,利用有限元分析软件ABAQUS仿真,将带钢的成型形状、边部纵向应变曲线、边部PEEQ(等效塑性应变)曲线作为评价指标,探讨了成型速度、摩擦状态对管坯成型效果的影响。结果表明,在正常取值下,速度和摩擦状态对成型形状无较大影响,速度对边部纵向应变以及边部PEEQ影响较大,摩擦因数对边部纵向应变影响较大,对边部PEEQ基本无影响。     

排辊成形底线参数对大口径焊管成形质量的影响

排辊成形底线形状会影响焊管成形质量,根据实际生产Φ508 mm焊管时的辊位参数建立排辊成形大变形有限元模型,依此辊位拟合出成形底线方程,并利用显式动力算法进行成形仿真。结果表明,此成形底线下预成形段板带边缘纵向应变不够均匀,辊位尚有优化空间。在此基础上,上、下调整成形底线,两次下调成形底线后得到较优辊位,并得到成形底线对预成形段板带边缘纵向应变和等效塑性应变的影响规律,即在预成形段,板带边缘在弯边辊和大压下辊处发生较大纵向应变,辊位下调使得预成形段板带边缘纵向应变趋于更均匀,但板带边缘等效塑性应变值变大。     

宝钢Φ610mmERW机组柔性成型辊位参数的确定

通过线性回归法计算出了宝山钢铁股份有限公司Φ610mmERW机组所有规格的排辊成型的辊位参数．其中尤为关键的是弯边、预成型段、线成型段这3个自由度最大的排辊成型部分;同时运用二次回归曲线,依据成型下山法（Downhill）,优化了排辊部分中的底辊辊位参数,真正实现了带钢柔性成型。经过统计分析计算确定的成型辊位参数已运用于该机组的大批量生产中。     

大连三高集团有限公司与番禺珠江钢管(连云港)有限公司签订高频直缝焊管生产线供货合同

<正>大连三高集团有限公司(简称三高集团)与番禺珠江钢管(连云港)有限公司于2011年4月11日在广州市签订了Φ711mm(28in)HFW直缝焊管生产线供货合同并正式生效。该Φ711mm HFW生产线的产品规格为:圆管Φ245~711mm×5~25mm,方矩管200mm×200~550mm×550mm,生产周期12个月。该生产线采用了具有三高集团自主知识产权的焊管成型技术,即开口成型部分采用空弯成型与全排辊成型相结合的成型     

中直径管线管用HFW焊管的开发及进展

主要介绍了国外HFW焊管企业在中直径管线管用厚壁HFW焊管的产品研发方面所涉及的技术和成熟做法,对提升我国中直径管线管用HFW焊管制造技术水平有所借鉴,也有利于利用现有制造资源和提升现有装备技术水平.通过产品拓展和研发,HFW焊管的外径已从610 mm扩大到660 mm,壁厚从20 mm以内提高到25.4 mm,并以良好的产品使用性应用在油气输送等工程中.分析认为:生产线的技术提升和装备完善,是中直径管线管用HFW焊管产品延伸拓展的有效手段.     

FFX成型技术的先进性分析

近50年来,HFW焊管成型技术经历了3个阶段的技术进步:传统成型-排辊成型-FFX成型。结合渤海石油装备华油钢管公司扬州分公司的实际应用情况,重点分析了FFX成型技术在其粗成型轧辊兼用和结构合理、控制系统高度的自动化水平、钢管易调型、设备运行全过程监控等方面的先进性以及运行的经济性。     

Research on strip deformation in the cage roll-forming process of ERW round pipes

Cage roll forming is an advanced roll-forming technique to manufacture electric resistance welded (ERW) round pipes. In the cage roll-forming process, many small rolls are arranged along the outer surface of the deformable strip to bend the strip edge in a more smooth way. Furthermore, these small rolls can be used for forming pipes of different sizes. Therefore, cage roll forming can reduce roll change time and improve forming quality, as compared with the conventional step roll forming. However, very few studies can be found about cage roll forming, due to its complexity, and the industrial practice depends greatly on experience rather than science-based design today. In this work, the whole cage roll-forming process is simulated with the explicit elastic–plastic finite element method, and the strip deformation during the cage roll-forming process has been investigated in detail. Through the simulation, the “non-bending area” phenomenon is found, and the ranges of the non-bending area at different forming stands are obtained. In addition, the longitudinal strain at the inside edge and center are predicted, and by comparison, it can be known that the deformation of the strip edge is usually larger and edge buckling is most likely to occur at the entry sides of No.1–No.3 fin-pass stands. Finally, the circumferential length, opening distance and the profiles of the deformed strip are measured on the cage roll-forming mill. There is a good agreement between the experimental and simulated results.     

I型扁钢轧制过程数值模拟

本文I型扁钢的生产坯料为钢带经卸卷、分条轧制后的窄钢条。采用有限元软件Msc.Marc建立了规格为25 mm×5 mm×3 mm的Q235 I型扁钢4道次热连轧的弹塑性有限元模型,研究了轧件在轧制过程中的变形情况、等效应力、等效塑性应变的变化规律。结果表明：轧件在立轧道次会出现轻微的狗骨形,平轧道次会出现轻微的单鼓形;轧件横断面的中间部位等效塑性应变较大;轧件边角部等效应力较大,轧制过程中易出现质量缺陷。     

Prediction of maximum initial strip width in the cage roll forming process of ERW pipes using edge buckling criterion

Cage roll forming is an advanced process for producing electric resistance welded (ERW) pipes. It is designed to improve the strip deformation and to increase the flexibility of production lines compared with the conventional roll forming of ERW pipes. One of the most important parameters of this process is the initial strip width. Accurate prediction of the initial strip width is vital for producing sound pipes with desired dimensional and geometrical tolerances. In this paper, cage roll forming process is simulated with the explicit elastic–plastic finite element method in the MSC Marc Mentat software. Simulation results show that by increasing the initial strip width, more circumferential length reduction is induced to the deformed strip in the fin-pass stands. This effect increases the difference of longitudinal strains at the edge and center of the deformed strip and consequently leads to a high longitudinal compression at the strip edge. Therefore, edge buckling will be unavoidable if the initial width is selected bigger than a specific limit. In order to predict the maximum initial width in cage forming process, an edge buckling criterion was introduced. The circumferential length and the horizontal distance between two deformed strip edges were obtained from the simulation and were compared with the experimental data from a production line. The comparison showed a good agreement and confirmed the finite element simulations.     

基于混合硬化模型的ERW焊管排辊成形数值模拟

针对ERW焊管排辊成形过程中带刚反复加载、卸载的复杂成形工艺特点,提出了考虑包辛格效应的混合硬化材料本构模型;通过ABAQUS用户材料子程序VUMAT的二次开发,对混合硬化材料的本构模型进行了有限元程序实现;基于混合硬化模型,对ERW焊管排辊成形过程进行了数值模拟,分析了成形过程中应力应变的变化规律,并对计算结果进行了对比。结果表明,混合硬化模型能够很好地体现ERW焊管排辊成形反复加载、卸载的成形工艺特点;不同的材料硬化模型对排辊成形过程中板料的应力应变产生较大影响。     

套管滚压整形力学分析及单次整形极限研究

滚珠整形器在变形套管修复中应用越来越广泛,而整形时常凭经验确定整形量,若单次整形量过大极易造成套管损坏。为此,给出套管单次整形极限研究方法,采用多线性等向强化模型,考虑套管的材料和接触双重非线性特性,建立了滚压整形缩径变形套管有限元模型,给出了求解策略,并采用试验研究的方法验证了数值模型的合理性。揭示了不同整形量对套管塑性位移及应力分布的影响规律,研究了不同轴向变形长度套管单次整形极限。结果表明:随着套管整形量的增大,套管最大等效应力、塑性位移和残余应力均增大;随着套管轴向变形长度的增大,单次整形极限有减小的趋势,单次整形量最大值不能超过3.6 mm。研究结果可为滚压整形变形套管现场施工提供理论指导。     

翼缘厚度80~120 mm重型热轧H型钢翼缘变形渗透研究

针对翼缘厚度80~120 mm重型热轧H型钢的开发,采用有限元模拟技术,对其变形过程进行了分析,研究了翼缘变形渗透情况。结果表明,翼缘厚度80~120 mm重型热轧H型钢变形后,距其翼缘内侧30%t_i处存在最小等效塑性应变区,即该部位变形渗透效果最差;成品翼缘厚大于100 mm时,翼缘心部与翼缘外侧总等效塑性应变均值之差约为0.10,变形渗透程度不良,在成品道次开轧前,将翼缘表面温度降至900 ℃左右,其变形渗透程度得到显著改善;成品翼缘厚小于100 mm时,随着中间坯翼缘厚度由95 mm减小至80 mm,其变形渗透良好,变形更加均匀。     

Predicting plastic deformation and work hardening during V-band formation

V-band clamps are manufactured using a cold roll forming process consisting of six passes which plastically deform an initially flat strip by bending to produce the band's V-section. In this paper a new method of validating numerically predicted plastic deformation in a cold formed metal strip is presented. Tensile testing of samples of the band's material was used to obtain a direct link between plastic strain and work hardness of this particular material. Using this correlation, the equivalent plastic strain (PEEQ) values predicted by finite element simulations were converted into hardness values. These values were compared to experimental work, in which samples of each pass of the roll forming process were taken to determine the work hardness in the cross section of the V-band using a micro-hardness machine. The error in strain predicted by the numerical method and hardness obtained by testing was found to be between 0.4% and 16.9%. This error was mainly due to uncertainty in material properties and the accuracy of the measurement technique. Compared to the more classical approach of measuring strain distribution with strain gauges, this method is more precise and accurate, as it is able to pick up even small changes in strain distribution.     

阳极板多道次辊弯成形过程数值模拟

利用有限元软件MAC.MARC,根据按辊弯成形工艺建立的辊花图,对阳极板多道次辊弯成形过程进行了数值模拟。基于动力显示算法,采用刚性辊轮沿板材长度方向运动的方式建立了阳极板多道次辊弯成形有限元模型。分析了成形过程中阳极板的Y向位移、等效应力与等效塑性应变的变化,重点研究了板材成形时等效塑性应变在弯曲角处的变化。结果表明,等效塑性应变的极值主要出现在当前道次所成形的弯曲角位置,且随成形弯曲角度的增大而增大。     

铝合金机匣体多向精锻工艺优化

采用多向精锻工艺生产机匣体锻件可显著提高材料利用率和生产效率,但由于机匣体形状复杂且7A04超硬铝合金塑性差、应变速率敏感性强,在锻造成形过程中容易出现充不满和折叠现象。通过塑性成形理论分析、热力耦合有限元模拟和实验研究相结合的方法,总结了材料的变形行为和成形规律,提出了坯料形状和预锻工艺的优化方法,解决了生产中出现的问题,得到了合格的锻件,并实现了产业化。     

GH4169合金叶片制坯成形工艺数值模拟优化

基于塑性有限元原理,应用Deform数值模拟平台,通过变形温度、压下量对挤杆成形及变形速度、摩擦条件对镦头成形的各场量进行深入研究,全面揭示了GH4169合金叶片制坯过程成形规律,并对其工艺参数进行优化.结果表明:适当的提升锻造温度有利于挤杆锻后温度的平稳分布;变形温度的增大使杆部各区域金属流动速度差异逐渐缩小,挤杆为...