| 摘要: |
| 通过理论推导及典型工况下筛网动力特性和颗粒运动轨迹的计算,研究逆循环椭圆力激振钻井液振动筛的筛 分过程。研究结果表明:水平筛网垂直方向加速度明显大于-9. 8 m/s2并处于上行阶段才容易产生液体透筛流动； 筛网垂直方向加速度越大，液体透筛速度越大;一个振动周期包括液体透筛段、颗粒抛掷段和过渡段,加速度椭圆上 部对应于筛网上行的区段为主要的液体透筛区;激振力幅相同时,逆循环椭圆筛液体透筛速度较大;逆循环激振时 颗粒向后抛掷明显,向前输运速度小于正循环激振工况，颗粒在筛面上停留时间长;颗粒向后抛掷能够诱导颗粒团 聚,减少颗粒透筛，并将许多嵌入筛孔的颗粒带出,可保持高的筛网开孔率,使外排钻屑干度大。现场应用表明,逆 循环椭圆力激振的筛分效果明显优于正循环激振工况，与理论研究一致。 |
| 关键词: 逆循环椭圆力 平衡椭圆运动 钻井液振动筛 筛分机理 颗粒团聚 |
| DOI：10.3969/j.issn.1673-5005.2010.02.021 |
| 分类号:TE 926 |
| 基金项目:国家“863”高技术研究发展计划项目(2006AA09A104) |
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| Screening mechanism of balanced elliptical motion shale shaker excited by backward elliptical vibrating forces |
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WANG Zong-ming, WANG Rui-he,XIAO Wen-sheng
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(College of Mechanical and Electronic Engineering in China University of Petroleum, Dongying 257061，Chirw,)
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| Abstract: |
| The screening mechanism of a balanced elliptical motion shale shaker excited by backward elliptical vibrating forces was studied based on theoretical derivation and calculation on dynamic characteristics of screen and moving track of particles. The results show that liquid can flow through screen smoothly if the vertical acceleration of a horizontal screen is much larger than -9. 8 m/s2 and when the screen is moving up. The penetrating velocity becomes larger with the vertical acceleration increasing. There is liquid penetrating stage, particles thrown stage and transition stage in a vibrating cycle. And the upper part of acceleration ellipse corresponding to screen moving up stage is the main penetrating stage for liquid. Backward elliptical vibrating forces with the same amplitude may produce larger penetrating velocity of liquid than that using forward cycle. Using backward cycle, particles can be transported forward more slowly, but the distance thrown backward is longer than that of forward cycle. Particles being thrown backward can result in particle agglomeration. And more small particles are prevented from penetrating screen and many particles in screen opening can be hauled out. With high percent opening of screen and long residence time on screen for particles, larger flow capacity and more dry cuttings can be expected.Field application shows that shakers excited by backward elliptical forces excelled ones with forward elliptical forces of the same amplitude in performance greatly, which confirms theoretical conclusions. |
| Key words: backward elliptical vibrating force balanced ellipticai motion shale shaker screening mechanism particle agglomeration |
