外压检测套管螺纹密封性装置的研究

发布时间：2018-02-28 17:08

本文关键词： 套管密封检测装置外压设计　出处：《西南石油大学》2015年硕士论文　论文类型：学位论文

【摘要】：现场油气田套管柱密封泄漏现象不仅对后续施工影响巨大,对环境和社会都会造成巨大的安全隐患。套管从合格出厂到下套管的过程中,可能会因为作业过程中的磕碰、员工的操作方式不当、连接扣和密封面的清洁程度不佳等因素影响套管连接的密封性。因此,在下套管过程中逐根对套管进行在线气密封检测是确保套管连接密封性的直接且有效的手段。现场已有部分油气井运用内压检测套管螺纹密封性装置对螺纹的密封性能进行在线检测,但内压检测装置在使用过程中仍然存在一些问题,包括检测操作不便、不利于进行小管径套管检测和可能出现落鱼现象等等。根据现场需求,针对内压检测装置的不足,本文提出了一种外压检测套管螺纹密封性能的方法,并完成了对装置的设计工作。本文的研究工作主要包括以下几个方面： (1)针对现场内压检测套管螺纹密封性装置在实际运用中存在的不足,提出了外压检测套管螺纹密封性的方法。 (2)研究常用套管螺纹的密封形式和密封机理,利用有限元仿真模拟内压和外压检测套管螺纹连接密封性的过程,分析内压和外压检测过程对套管密封部位的等效应力和接触应力的影响,作出了外压检测套管螺纹密封性装置是可行的结论。 (3)根据外压检测装置所处工况和需要实现的功能,借鉴井控设备中成熟的防喷器原理,通过对密封性检测方式和装置抱紧方式的选择完成了对外压检测套管螺纹密封性装置的结构设计。 (4)对装置中的橡胶密封材料完成单向拉伸和单向压缩实验,对实验数据拟合Mooney-Rivlin本构模型、Ogden本构模型和Yeoh本构模型,最终判定Yeoh本构模型的拟合结果能够更好地反应所选橡胶材料的力学特性。 (5)通过对密封结构重要参数的理论研究,完成对密封胶芯的结构设计。依靠有限元仿真手段,分析讨论偏心距e、半径差△、垫铁内弧面偏心距et和垫铁外圆弧半径R2对密封效果的影响,并选择针对本装置密封胶芯的较优尺寸参数。 (6)完成对液压缸的结构设计和液压控制系统的设计,校核承压部件外壳强度,优化外壳的结构尺寸。
[Abstract]:The leakage phenomenon of casing string seal in field oil and gas field will not only have a great impact on the subsequent construction, but will also cause huge safety risks to the environment and society. Improper operation of employees, poor cleanliness of connection buckle and sealing face and other factors affect the sealing of casing connection. On-line gas seal detection is a direct and effective means to ensure casing connection sealing in the process of casing down-casing. Some oil and gas wells have used internal pressure to detect casing thread sealing device for thread density. Seal performance online testing, However, there are still some problems in the use of the internal pressure detection device, including the inconvenient operation of the test, which is not conducive to the detection of small pipe diameter casing and the possibility of falling fish, etc. According to the requirements of the field, the defects of the internal pressure detecting device are pointed out. In this paper, a method of testing casing thread sealing performance by external pressure is presented, and the design of the device is completed. The research work of this paper mainly includes the following aspects:. 1) in view of the deficiency of in-situ pressure testing casing thread sealing device in practical application, the method of external pressure testing casing thread sealing property is put forward. The sealing form and sealing mechanism of common casing thread are studied, and the process of testing the sealing property of casing thread connection is simulated by finite element simulation. The influence of internal pressure and external pressure on the equivalent stress and contact stress of casing sealing position is analyzed. The conclusion is made that it is feasible to detect casing thread sealing device by external pressure. According to the working condition and the function that need to be realized, the principle of blowout preventer, which is mature in well control equipment, is used for reference. The structural design of the casing thread sealing device for external pressure testing is completed by selecting the sealing test mode and the device holding mode. (4) uniaxial tensile and uniaxial compression experiments were carried out on rubber sealing materials in the plant. The Mooney-Rivlin constitutive model and the Yeoh constitutive model were fitted to the experimental data. Finally, the fitting results of Yeoh constitutive model can better reflect the mechanical properties of the selected rubber materials. Through the theoretical research on the important parameters of sealing structure, the structural design of sealant core is completed. By means of finite element simulation, the eccentricity and radius difference are analyzed and discussed. The influence of inner arc eccentricity et and outer arc radius R2 of cushion iron on sealing effect was studied and the optimum size parameters of sealing core were selected. The structure design of hydraulic cylinder and the design of hydraulic control system are completed. The strength of the shell of the pressure bearing parts is checked and the structural dimensions of the shell are optimized.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE931.2

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