钻柱动力失稳现象的初步研究

A Dynamic Study of the Hoisting System on ZJ45J Drilling Rigs

随时间波动的钻压作用在钻柱的底部,钻柱有可能出现动力失稳而产生大幅度的弯曲振动。文章在给出钻柱的横向振动微分方程后,确定了钻柱的动力不稳定区域,分析了这几个区域的特点,指出:主要动力不稳定区域最宽,也是最危险的。在钻井操作过程中,应尽量避免在动力不稳定区域内工作,用改变转盘转速、改变钻压以及合理选择钻具组合等方式可以实现这一目标。

The author analyzes the oscillogram and data obtained from the dynamic tcst for the hoisting system on ZJ45J drilling rigs, recommends parametcrs valid for practical application. In addition, the author makes a special study on the hoisting dynamics of the hoisting system of the rig. A mechanical model of multi-degrec- of-freedom is established and differential equations of motion are set up. The solution of the equation set and the coefficient of dynamic load are searched by Timoshenko's theory and calculated on electronic computer.