【摘要】 以钳牙花型与当量摩擦系数的关系为切入点,基于接触力学及摩擦学原理,对钳牙与管柱接头外壁接触进行受力分析,建立了钳牙牙型角、牙顶倒角半径、管柱外径及咬痕深度与当量摩擦系数的关系式;对钳牙及管柱强度,以及钳牙齿磨损原因进行了分析。在摩擦力矩满足上卸扣要求、不损伤管柱等约束条件下,利用正交设计分析了钳牙齿与管柱外壁接触时4个因素对当量摩擦系数的影响程度。结果表明:钳牙牙型角对当量摩擦系数影响最大,而牙顶倒角半径的影响几乎可以忽略不计。为使咬痕深度小于1 mm,对于常用直径系列管柱,钳牙牙型角的最佳取值为80°～100°。更多还原

【Abstract】 The nonlinear occlusal contact stress between the clamp tooth of iron roughneck and the external wall of pipe string joint is studied by means of the relationship between the pattern of clamp tooth and equivalent friction coefficient based on the principles of contact mechanics and tribology,and the relationship between equivalent friction coefficient and teeth shape angle,teeth roof chamfer radius,the external diameter of pipe string and bite depth was established.The strength of clamp tooth and tube string and the causes of tooth wear were analyzed.The sensitivity of the influences of tooth shape angle,teeth roof chamfer radius,the external diameter of pipe string and bite depth on equivalent friction coefficient was analyzed by means of orthogonal test.The results show that the influence of the teeth shape angle on the equivalent friction coefficient is the greatest,while the influence of teeth roof chamfer radius can be neglected.For common diameter series of pipe string,in order to make the bite depth less than 1 mm,the optimal value of the tooth shape angle should be 80 °～ 100 °.更多还原