镍基双金属管件复合成型技术研究

发布时间：2018-06-19 05:43

本文选题：复合管件 + 热处理　；参考：《扬州大学》2017年硕士论文

【摘要】：镍/L360钢双金属复合管以其卓越的耐腐蚀性能、力学性能和加工性能正逐渐成为高含CO2、Cl-和H2S、高温、高压等恶劣油气田环境中管线运输的重要选择之一。但时至今日,对其材料性能和成型规律尚缺乏较为科学、系统的研究。本文采用理论与试验相结合的方法,比较了不同热处理工艺对管材力学性能的影响,并通过有限元模拟的方法确定了复合管液压胀形的工艺参数匹配,成功制备出了满足使用要求的大口径镍/L360钢双金属复合三通管。针对不同热处理工艺对材料性能的影响,采用光学显微镜(OM)、扫描电镜(SEM)以及维氏硬度计、万能试验机等分析试样显微组织和力学性能变化,进行最佳热处理工艺的选择。结果表明:采用940℃固溶水冷+520℃回火处理工艺的试样L360钢部分显微组织向回火索氏体转变完全,镍基部分固溶强化作用明显,晶间腐蚀敏感度降低,双金属界面结合性能最好。利用有限元软件ABAQUS对镍/L360钢复合三通管的液压胀形进行模拟,分析了不同轴向进给量、内压力及加载路径对管件壁厚分布与成型极限的影响。结果表明:在内压力100MPa,双线性加载路径,摩擦系数0.06的工艺条件下,胀形效果最佳,支管高度在轴向进给量为32mm时达到最大,支管胀形高度为47.39mm;当轴向进给量达到32.7mm时,外管首先发生失效。以仿真获得的冷挤压工艺参数为依据,设置三通管940℃退火热成型的工艺参数,成功制备大口径镍/L360钢复合三通管。其支管胀形高度约80mm,最大减薄率≤12%,观察无明显开裂与双金属界面分离,满足实际使用需求。
[Abstract]:With its excellent corrosion resistance, mechanical properties and processing properties, nickel /L360 steel bimetallic composite pipes are becoming one of the most important options for pipeline transportation in the environment of high CO2, Cl- and H2S, high temperature, high pressure and other bad oil and gas fields. But today, the material properties and molding rules are still lack of scientific and systematic research. The influence of different heat treatment processes on the mechanical properties of the pipe is compared with the experimental method, and the process parameters matching of the hydraulic bulging of the composite pipe is determined by the finite element method. The double metal duplex three pipe with large diameter nickel /L360 steel is successfully prepared. The effect of optical microscopy (OM), scanning electron microscopy (SEM), Vivtorinox hardness tester and universal testing machine were used to analyze the microstructure and mechanical properties of the samples. The optimum heat treatment process was selected. The results showed that the microstructure of L360 steel in the sample of 940 C solution cooling +520 C tempering process was turned to the tempered Soxhlet. The nickel base partial solid solution strengthening effect is obvious, the intergranular corrosion sensitivity decreases and the bimetallic interface bonding performance is the best. The hydraulic expansion of the nickel /L360 steel composite three pipe is simulated by the finite element software ABAQUS, and the influence of the different axial feed, internal pressure and loading path on the wall thickness distribution and forming limit of the pipe fittings is analyzed. The results show that under the internal pressure 100MPa, the bilinear loading path and the friction coefficient of 0.06, the bulging effect is the best, the height of the branch pipe reaches the maximum when the axial feed is 32mm and the tube bulging height is 47.39mm. When the axial feed is reached to 32.7mm, the outer tube is first invalid. The simulation results are based on the cold extrusion process parameters. The process parameters of annealing and thermoforming of three pipe at 940 C were successfully prepared. The large diameter nickel /L360 steel composite three pipe was successfully prepared. The bulging height of the branch tube was about 80mm and the maximum thinning rate was less than 12%. There was no apparent cracking and the separation of the bimetal interface.
【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG306;TG166.7

【相似文献】