BTA深孔钻杆的涡动研究

The Research of Whirling of the Boring and Trepanning Association(BTA)Drill

对BTA深孔钻杆在加工过程中的涡动问题进行研究。分析了在切削液作用下BTA钻杆与内孔接触与非接触时的钻杆受力情况,得到钻杆在涡动面上的运动平衡方程,推导出钻杆发生涡动的理论涡动点和钻杆脱离内孔的理论阀值点。总结出钻杆因不平衡量作用时产生的偏心距小于理论涡动点时,钻杆不会产生涡动,即使存在最终也会因切削液流体力作用而消失;同时涡动角频率的绝对值小于理论阀值时,钻杆会脱离孔壁,而涡动角频率达到阀值后,钻杆运动就可能发展成为沿孔壁反向滚动的定常涡动。所得结论对BTA深孔加工的动态稳定性研究,尤其是对钻杆扰动和偏心现象的研究,具有理论和实际意义。

It expounds the whirling motion phenomenon of the BTA drill deep hole processing process. Under the cutting fluid＇ s effect, the stress situation of BTA drill pipe are analyzed with contacting hole wall as well as isolating hole. The movement balance equation of drill pipe on their whirling surface is derived, then the theory whirling point of drill pipe whirling and the theory value point of drill pipe isolating from the hole are achieved. A conclusion is gained that the drill pipe won＇t whirl when the eccentricity resulting from the amount of unbalance effects is less than the theoretical vortex point, and even if it will whirl, it disappears eventually for the physical action of cutting fluid flow. The conclusion also obtains that the drill pipe will leave from the hole wall if the absolute value of whirling angular frequency is less than the threshold, and the drill pipe movement may become steady whirling with reverse rolling along the wall of hole when whirling angular frequency reach to the threshold. Finally, the results have important theory and practical siguificances on the study of dynamic stability of BTA deep hole drill, especially the study of driU pipe disturbance and eccentric phenomenar~