液态介质下钻探机具硬质合金材料的摩擦学行为研究

发布时间：2018-01-29 02:12

本文关键词： 液态介质钻探机具硬质合金摩擦学有限元分析　出处：《中国地质大学(北京)》2015年硕士论文　论文类型：学位论文

【摘要】：本论文着眼于研究钻探材料在液态介质下的摩擦磨损行为,研制专门针对钻探材料摩擦学测试的试验机附属装置,使其能够满足实际液态工况测试条件;研究了钻探材料在不同液态介质及载荷下的摩擦学特性,系统研究了硬质合金材料在不同摩擦因素下的摩擦因数、磨损率、表面粗糙度和表面磨损形貌,分析了不同摩擦因素对材料的影响;并进一步探究了硬质合金球面静接触的行为分析。结果表明:(1)设计的试验机附属测试机构,能够满足钻探材料的液态工况测试要求。主要包括上盖、套筒和工作台三部分,加装附属测试机构后可满足钻探活动零部件在干态、水态及水基泥浆等液态工况下的摩擦学性能测试。采用ANSYS软件分析了主体部分工作台的结构强度,并对工作台结构进行了优化设计。结果表明,在静载荷作用下的工作台应力及应变在合理范围内,优化后的工作台体积在安全边界内最小,满足机构设计要求,能够保障试验机运行的安全性。(2)钻探硬质合金材料在不同的润滑介质及不同载荷下的测试表明,在干摩擦和水润滑下的平均摩擦因数分别为0.3和0.2,水基泥浆润滑下的摩擦因数为0.15,干摩擦和水润滑下的摩擦因数远高于水基泥浆,且水基泥浆下的磨损率和粗糙度都小于干摩擦和水润滑,可见水基泥浆具有良好的润滑特性;硬质合金材料在水基泥浆状态下,载荷为10 N时摩擦因数为0.12,15 N时为0.15,20 N时为0.18,可见在水基泥浆状态下,载荷对材料的摩擦磨损行为影响不大;在干摩擦下,硬质合金的磨损主要为磨粒磨损和疲劳磨损,且以疲劳磨损为主。在水润滑状态下,试样的磨损主要是腐蚀磨损,在水基泥浆状态下,以边界润滑为主,同时存在一定的磨粒磨损。(3)基于赫兹接触理论,对硬质合金球面静接触进行有限元分析。在相同载荷作用下,当摩擦因数不同时,对球面最大接触应力和接触斑半径的影响很小;当摩擦因数相同而载荷不同时,球面接触间的接触应力和半径随载荷增大逐步增大。将ANSYS分析结果与Hertz理论计算进行对比可以看出,二者存在一定的误差,但ANSYS分析更准确可靠。
[Abstract]:In this paper, the friction and wear behavior of drilling material in liquid medium is studied, and the accessory device of testing machine for tribological test of drilling material is developed, which can satisfy the actual testing condition of liquid state. The tribological characteristics of drilling materials under different liquid medium and load were studied. The friction coefficient, wear rate, surface roughness and surface wear morphology of cemented carbide materials under different friction factors were systematically studied. The influence of different friction factors on the material is analyzed. Furthermore, the behavior analysis of static contact of cemented carbide spherical surface is studied. The results show that the testing mechanism of the testing machine designed by 1: 1) can meet the testing requirements of drilling materials under liquid condition, mainly including the upper cover. The three parts of sleeve and workbench can be used to meet the dry-state of drilling movable parts after the installation of subsidiary testing mechanism. The tribological properties of the worktable under liquid conditions such as water state and water-based slurry are tested. The structural strength of the main worktable is analyzed by ANSYS software and the structure of the worktable is optimized. The results show that the structure of the worktable is optimized. Under static load, the stress and strain of the worktable are within a reasonable range, and the optimized worktable volume is minimized within the security boundary, which meets the design requirements of the mechanism. The test results of drilling cemented carbide materials under different lubricating medium and different loads show that. The average friction coefficient under dry friction and water lubrication is 0.3 and 0.2 respectively, and the friction coefficient under water based slurry is 0.15. The friction coefficient of dry friction and water lubrication is much higher than that of water based mud. The wear rate and roughness of water-based mud are lower than that of dry friction and water lubrication. When the load is 10 N, the friction coefficient of cemented carbide material is 0.12 ~ (15) N and 0.15 ~ (20) N is 0.18, which can be seen in the state of water-based mud. The load has little effect on the friction and wear behavior of the material. Under dry friction, the wear of cemented carbide is mainly abrasive wear and fatigue wear, and fatigue wear. Based on Hertz contact theory, the static contact of cemented carbide spherical surface is analyzed by finite element method. Under the same load, the friction coefficient is different. It has little effect on the maximum contact stress and contact spot radius of spherical surface. When the friction coefficient is the same and the load is different, the contact stress and radius of spherical contact increase gradually with the increase of load. The results of ANSYS analysis are compared with that of Hertz theory. However, ANSYS analysis is more accurate and reliable.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P634.4

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