STUDY ON PRECISE CONTROL OF DRILLING ANGLE OF ORIENTATION DEVICE

Since effect of smooth(pre-split) blasting depends largely on the parallel degree of drilling,it is key that measuring and regulating drill posture conveniently,fast and accurately before drilling.An advanced high-precision electronic compass was installed in the drill holder in order to monitor the three-dimensional drill-arm posture and the drilling direction,which adjusts error of the drilling direction by time.So,the parallel degree of the drilling meets the design requirement.Comparing with GPS devices developed by foreigners,this electronic compass is not only inexpensive,but overcomes the shortcomings that GPS is impacted by the strength of satellite signal,which makes its measurement more accurately and quickly.With the application of this device in the blasting work of Beijing-Shanghai high-speed railway,high-quality smooth blasting effect was obtained and the parallel degree of borehole deviation was less than 1°.