双端内加厚铝合金钻杆挤压成形数值模拟

发布时间：2018-04-26 14:02

  本文选题：铝合金钻杆 + 挤压成形　； 参考：《西南石油大学》2017年硕士论文

【摘要】：随着油气勘探技术的发展与进步,国内外油气开采的发展方向逐步转向深井/超深井、大位移井及含硫化氢和二氧化碳的油气井。在这些油气井的勘探与开采中,铝合金钻杆凭借良好的力学性能、耐腐蚀性能而在世界范围受到广泛关注并得到推广应用。但相较俄罗斯、美国等铝合金钻杆主要生产国,我国铝合金钻杆的生产尚处于试制阶段,且在管体成形工艺及质量上存在诸多待攻关问题。因此,开展铝合金钻杆成形工艺、质量及材料设计等方面的研究,对于指导我国铝合金钻杆成形工艺优化,加快我国铝合金钻杆研制及批量化生产进度有着重要的意义。本文采用Deform-3D数值模拟软件,分别模拟7075铝合金及15%volSiCp/7075复合材料Φ73 mm双端内加厚钻杆的一次挤压成形过程,从成形过程中坯料的应力云图、管体的等效应变分布及成形后管体内、外表面的损伤、动态再结晶及几何尺寸偏差方面分析工模具几何形貌及挤压工艺对管体成形及质量的影响,得到两种材料的Φ73 mm双端内加厚钻杆管体挤压成形的优化工艺;其后,通过对比分析两种材料在优化挤压工艺下的管体成形质量,重点探讨采用7075铝合金与15%volSiCp/7075复合材料挤压成形的Φ73 mm双端内加厚钻杆在管体外表面损伤因子、动态再结晶及几何尺寸偏差等方面的差异,对比各成形工艺要素对管体成形质量的影响程度;再次,采用卧式挤压机分别挤压成形Φ73 mm钻杆的内加厚段及主体段,通过观察两段管体的金相组织,验证数值模拟中挤压钻杆动态再结晶分布规律;最后,采用Deform-3D软件模拟单颗粒的6.5%SiCp/7075复合材料的压缩变形过程,从压缩变形过程中基体、界面、颗粒的应力、温度及基体的应变、损伤上探讨界面层材料及颗粒形貌对微单元压缩变形行为的影响。模拟及实验研究表明,采用空心坯料一次挤压成形的Φ73 mm双端内加厚7075铝合金钻杆管体上,管体后端外表面存在损伤因子高、外表面动态再结晶百分数及动态再结晶晶粒平均尺寸轴向差距大,且外径、壁厚偏差严重等问题。当钻杆材料为7075铝合金时,Φ73 mm双端内加厚钻杆的优化工模具形貌是平锥模的模角为63°、穿孔针锥形段长度为12.5 mm,优化挤压工艺参数是挤压比为25、挤压温度为400℃、挤压速度为1.12 mm/s;当钻杆材料为15%volSiCp/7075复合材料时,Φ73 mm双端内加厚钻杆的优化工模具形貌是平锥模的模角为60 °,穿孔针锥形段长度为12.5 mm,优化挤压工艺是挤压比为25、挤压温度为380℃、挤压速度为1.52mm/s。对于6.5%volSiCp/7075复合材料的压缩变形,当采用Si02作为界面材料且颗粒形貌为球体时,基体的损伤因子相对最小。
[Abstract]:With the development and progress of oil and gas exploration technology, the development direction of oil and gas production at home and abroad has gradually shifted to deep well / ultra deep well, long reach well and oil and gas well containing hydrogen sulfide and carbon dioxide. In the exploration and exploitation of these oil and gas wells, aluminum alloy drill pipes are widely concerned and widely used in the world because of their good mechanical properties and corrosion resistance. However, compared with Russia and the United States, the production of aluminum alloy drill pipe in China is still in the stage of trial production, and there are many problems to be solved in the forming process and quality of the pipe body. Therefore, the research on forming process, quality and material design of aluminum alloy drill pipe is of great significance in guiding the optimization of aluminum alloy drill pipe forming process in China and speeding up the development and batch production of aluminum alloy drill pipe in China. In this paper, Deform-3D numerical simulation software is used to simulate the forming process of 7075 aluminum alloy and 桅 73 mm 桅 73 mm double end thickened drill pipe respectively. The stress cloud diagram of the billet, the equivalent strain distribution of the tube and the body of the tube after forming are obtained from the stress cloud diagram of the billet during the forming process. The effects of die geometry and extrusion technology on tube forming and quality were analyzed from the aspects of external surface damage, dynamic recrystallization and geometric dimension deviation. The optimized forming process of 桅 73 mm double end thickened drill pipe tube with two kinds of materials was obtained. Then, by comparing and analyzing the tube forming quality of two kinds of materials under the optimized extrusion process, the damage factors of 桅 73mm double-end inner thickened drill pipe formed by extruding 7075 aluminum alloy and 15%volSiCp/7075 composite material outside the tube are discussed emphatically. The differences of dynamic recrystallization and geometric dimension deviation are compared to compare the influence of various forming process factors on the forming quality of pipe. Thirdly, the inner thickening section and main section of 桅 73 mm drill pipe are extruded by horizontal extruder respectively. The dynamic recrystallization distribution of extruded drill pipe in numerical simulation is verified by observing the metallographic structure of two-stage tube. Finally, the compression deformation process of 6.5%SiCp/7075 composite material with single particle is simulated by Deform-3D software, and the matrix and interface are simulated during compression deformation. The effects of interfacial layer materials and particle morphology on the compressive deformation behavior of microelements were investigated on the basis of stress, temperature, matrix strain and damage. The simulation and experimental study show that the outer surface of the 7075 aluminum alloy drill pipe with 桅 73 mm double end thickening has high damage factor on the outer surface of the tube, which is formed by single extrusion of hollow billet. The dynamic recrystallization percentage of the outer surface and the average grain size of the dynamic recrystallization have a large axial gap, and the external diameter and wall thickness deviation are serious. When the drilling pipe material is 7075 aluminum alloy, the optimum die shape of 桅 73 mm double end internal thickening drill pipe is 63 掳for flat cone die, 12.5 mm for the length of tapered section of perforated needle, and 25 for extrusion ratio and 400 鈩，

本文编号：1806317