Abstract: Three quarters of global newly-additional recoverable reserves come from old oil and gas areas each year. A large number of old low-yield wells appeared one after another during the period of low oil price. It is of vital importance to tap potentials for higher production in the old oil and gas areas. Use of sidetracking horizontal well for old well has some technological advantages, such as low cost for each ton of oil and substantial increase in single-well yield. It is supposed to become an important technological measure for stimulation of low-yield oil and gas wells in the old areas. This technological measure is supposed to draw attention from oil and gas field managers and drilling workers. It should be put into wide application as soon as possible. This paper briefs about conceptions of sidetracking horizontal well, current technological development in this area and application results both at home and overseas. It points out that the next-stage research should be focused on radial sidetracking horizontal well, air sidetracking, water-free fracturing completion of sidetracking well, and coiled tubing sidetracking. The remaining oil and gas distribution should be continually clarified on the basis of in-depth research on oil and gas reservoir engineering. The relatively concentrated remaining oil and gas can be produced by using sidetracking horizontal well for old wells, thus improving production factor of oil and gas in the areas and dramatically boosting economic performance of development.

摘要： 世界每年新增可采储量的3/4 来自老油气区。低油价时期，在大量低产老井不断产生的情况下，老油气 区挖潜增产十分关键。老井侧钻水平井具有吨油成本较低、提高单井产量较大的技术优势，应成为老区低产井改造增 产的重要技术措施，引起油气田管理者和钻井工作者的高度关注，尽早投入规模应用。介绍了侧钻水平井的理念、技 术发展现状及国内外应用效果，指出下一步应加大径向侧钻水平井、气体侧钻、侧钻井无水压裂完井、连续管侧钻等 方向的攻关力度，在深入研究油气藏工程的基础上，不断明确剩余油气分布，利用老井侧钻水平井把相对集中的剩余 油气开采出来，以提高区域油气采收率，大幅度提高开发经济效益。

关键词: 老油气区, 侧钻井, 水平井, 降本增效, 连续管钻井, 分支井