不同振型振动筛的岩屑运移和堵筛规律研究

为降低钻井振动筛堵筛率并提高岩屑处理量,对不同振型下振动筛堵筛率和椭圆振动筛不同运动轨迹下岩屑运移规律开展研究非常必要。鉴于此,基于离散元法与振动筛运动理论,建立了不同轨迹振动筛运动模型,对岩屑在筛网上运移过程进行仿真。分析了振动筛不同振型时的岩屑堵筛规律,研究了椭圆振动筛不同长轴方向角与椭圆度时岩屑的运移速度和透筛率的变化规律。研究结果表明:椭圆振动筛的脱筛能力最强,圆振动筛其次,直线振动筛最弱;椭圆振动筛振幅大小一定,轨迹椭圆长轴方向角为45°时,岩屑运移速度最大;椭圆振动筛X方向振幅一定时,岩屑运移速度随轨迹椭圆度的减小而增大,透筛率随轨迹椭圆度的减小而减小。研究结果对提高振动筛筛分性能具有一定意义。

Study on Cuttings Migration and Screen Plugging of Shale Shaker Screens with Different Vibration Modes

To reduce the screen plugging rate of shale shaker and increase the processing amount of cuttings,it is necessary to study the screen plugging rate of shale shaker under different vibration modes and the cutting migration under different motion track of elliptical vibrating shale shaker. Based on the discrete element method and the theory of shale shaker motion,the motion model of shale shaker with different vibrating trajectory is established to simulate the migration of cuttings on the screen. The cutting plugging under different shale shaker vibration modes are analyzed. The variation of cutting migration velocity and cutting sifting rate of elliptical vibrating shale shaker with different long-axis direction angle and ellipticity is studied. The results show that the elliptical vibrating shale shaker has the largest sieving ability,followed by the circular vibrating shale shaker,and then the linear vibrating shale shaker. Given the same vibrating amplitude,the elliptical vibrating shale shaker has largest cuttings migration velocity under the trajectory ellipse long axis direction angle of 45°. Given a constant X direction vibration amplitude of the elliptical vibrating shale shaker,the cutting migration velocity increases with the decrease of the ellipticity of the vibrating track,and the sifting rate decreases with the decrease of the ellipticity of the vibrating track. The study results have certain significance for improving the screening performance of shale shaker.