共查询到20条相似文献,搜索用时 78 毫秒
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本文介绍了数控弯管机弯管时的回弹补偿、起弯点修正和精确下料的处理方法,以及使用“智能弯管测量仪”测取并提供弯管工艺参数和为数控弯管机提供补偿修正加工数据的方法. 相似文献
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以国标GB/T和美标ANSI碳钢管为测试对象,采用船舶管系自动化生产线的2D德系数控弯管机,测试碳钢管在先弯后焊和先焊后弯条件下的各种工艺参数,分析不同工艺参数下的弯管回弹角、延伸率及椭圆度等质量参数,形成新2D弯管工艺.结果表明:新工艺参数可以有效地保证弯管质量,满足规范和工艺的要求,提高成品弯管的合格率;同时能提高... 相似文献
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提出冷弯和热弯的区别和应用,弯管的几个参数包括弯模、起弯点、弯头圆弧长度、下料长度等的概念及基本计算,弯管机弯模在Tribon中的设置和应用,可作为设计人员的参考。 相似文献
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介绍了采用新式液压数控弯管机对大口径钢管进行无余量弯管的新工艺。主要以通径DN125-200mm管为对象,阐述了下料长度、弯曲后管材回弹角、无余量切割长度等的确定和计算方法。简要分析了该工艺所取得的效益。 相似文献
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机械式弯管机的设计与应用 总被引:1,自引:0,他引:1
本文介绍的机械式弯管机,采用三相电机提供动力并采用蜗轮减速机、齿轮组等传动减速和提高输出转矩,使用可调式限位开关进行折弯角度调整,采用多组弯管轮组合完成多种规格管料的弯制。该工具结构简单,实用、易于操作,实用性突出。 相似文献
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本文首次提出以回弹后半径作为参数讨论管子伸长量。管子伸长量的变化规律已通过实验获得,但其结果尚待理论上的进一步分析、说明。在实验研究的基础上,本文提出了确定无余量弯管工艺参数的一种新方法,也可用来作为数控弯管机的数学模型使用。 相似文献
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管壁不连续对管路中传播的弯曲波的隔离 总被引:1,自引:0,他引:1
采用梁弯曲振动的运动方程来求解管壁中传播的弯曲波,然后用传递矩阵的方法得出了弯曲波在通过管壁不连续段后的透射系数矩阵。利用边界条件,分析了管壁材料不连续段及其在管路中的布置情况对弯曲波透射系数的影响,并得出了如下结论:作为管路不连续段的铜管、铝管和挠性胶管都可以对管路中传播的弯曲波起到隔离作用,但它们也都有可能使振动放大。这与频率、边界条件和管路不连续段的布置密切相关;对极低频弯曲波的隔离是十分困难的,甚至是不可能的;管路不连续段的布置情况、管路边界条件(即支撑情况)和频率应当是管路隔振设计中需要特别注意的因素;挠性胶管在可以起隔离作用的条件下能够取得比铜管和铝管更低的透射系数和更大的位移补偿。 相似文献
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由于限弯器设计涉及多参数且缺乏理论模型与设计依据,导致设计效率低下.本文首先基于欧拉-伯努利梁理论建立了限弯器等效刚度的总体模型,同时采用板弯曲理论与Hertz接触理论建立局部锁合结构的弯曲模型,通过简化得到了模型的半经验求解形式,并定性研究了公头端部高度、有效节长、母头尾部厚度、材料弹性模量四类参数对等效弯曲刚度的影响规律.然后建立有限元分析模型验证了上述半经验求解形式,并引入正交试验研究上述四类参数对等效弯曲刚度的影响程度,验证了理论分析得到的各参数影响趋势.研究获得的限弯器等效弯曲刚度理论模型,以及上述四类参数变化对限弯器等效弯曲刚度的影响规律及程度,可为设计提供参考. 相似文献
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Flexible pipes are key equipment for offshore oil and gas production systems, conveying fluids between the platform and subsea wells. The structural arrangement of unbonded flexible pipes is quite complex, encompassing several layers with polymeric, metallic and textile materials. Different topologies and a large amount of intricate nonlinear contact interactions between and within their components, especially because of the relative stick-slip mechanism during bending, makes numerical analysis challenging. This paper presents an alternative three-dimensional nonlinear finite element model that describes the response of flexible pipes subjected to combined axisymmetric and bending loads. To simulate the response of a flexible pipe under axial tension or compression combined with uniform curvature, an equivalent thermal loading is employed on the external sheath, which is modelled as an orthotropic thermal expansion material with temperature-independent mechanical properties. To assess the feasibility of the proposed model, the bending moment versus curvature of the finite element solution is compared with experimental results obtained in literature and good agreements are found between them. Detailed finite element results such as contact pressures, armour wire slip displacements and friction, normal and transverse bending stresses are also shown and compared with available analytical models. 相似文献
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铜镍合金管在舰船海水管系中的应用 总被引:1,自引:0,他引:1
铜镍合金管(B10)耐海水冲刷腐蚀性能优良,腐蚀的温度敏感性较低,且具备优良的抗污性能,已在舰船海水管系中大量应用。在收集了铜镍合金管在舰船海水管系中的应用情况的基础上,对存在的问题作了分析,并对今后的海水管路设计提出了建议。 相似文献
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《Marine Structures》2006,19(4):193-216
The use of a pipe subject to bending moment with an equivalent plate subject to tension has been tried by a few researchers to avoid the complexity usually involved with experimental crack growth investigations of pipes with initial surface flaws. This approach also minimizes the use of more sophisticated monitoring instruments, thereby offering significant cost savings. This equivalency has been done for both experimental and finite element investigations. This paper studies the validity of this approach and evaluates the ranges of the crack depth ratio and elliptical crack diameter ratio for which this approach would be admissible. A series of finite element analysis was carried out to both verify the values of the stress intensity factors reported in the literature, and verify the results of the interpolation function used in the computational simulation in this research. Based on the computational simulations and demonstrating that the crack front follows a semi-circular shape during its growth, a dimensionless relationship between the stress intensity factor of a pipe under bending moment and that of a plate under pure tension has been introduced. A series of experimental investigation was performed to verify the validity of the proposed computational simulation. The results show the rationality and admissibility of this approach when considering the fatigue crack growth of pipes under bending. 相似文献