深井超深井钻机自动送钻研究探讨

自动送钻的目的是使钻头对井底的钻压保持设定的恒压值，实现最优化钻井的目的。当前深井超深井钻机自动送钻是通过绞车、天车、游动滑车、钢丝绳、大钩来进行的，由于绞车、游动系统存在动载，钢丝绳振动，大钩送钻速度明显不均匀，使井底钻压不稳定，难以实现较准确送钻。阐述了绞车游动系统送钻的工作原理和液压盘式刹车自动送钻、辅助电机自动送钻方法。提出精确自动送钻的理想方案是采用液压缸送钻系统，采用无绞车液压缸升降式钻机，液压缸系统自动送钻并担负起下钻具任务;也可用绞车起下钻具，液压缸自动送钻方案，彻底消除绞车、游动系统对自动送钻的干扰。

Study on Automatic Bit Feed of Deep and Ultra-deep Drilling Rig

The purpose of automatic bit feed is to keep the designed constant pressure value of bit weight at the bottom hole and achieve optimized drilling. The current automatic bit feed of deep and ultra-deep drilling rig is realized by winch, top pulley, swimming pulley, wire rope and hook; as the dynamic load of winch and hoisting system, the vibration of wire rope and the obvious uneven speed of bit feed by hook make bit weight at the bottom hole unstable and accurate bit feed is difficult. The paper describes the working principle of bit feed by hoisting system and the methods of automatic bit feed by hydraulic disc brake and auxiliary motor. It is put forward that the ideal solution for accurate automatic bit feed is to use the hydraulic cylinder system. By hydraulic cylinder lift rig without winch system, hydraulic cylinder system can automatically fulfill bit feed and round trip; and winch and hydraulic cylinder can be separately used for round trip and automatic bit feed to eliminate the interference of winch and hoisting system to automatic bit feed.