利用井底超高压射流提高钻速研究

RESEARCH ON ENHANCING DRILLING SPEED BY USING ULTRA-HIGH PRESSURE JET STREAM IN BOTTOM HOLE

近10年以来，机械辅助高压射流破岩技术再次获得钻井界高度重视，被认为是提高硬地层、深井机械钻速的根本途径之一。利用井底超高压射流钻井技术是指基于水力与机械联合破岩方法和水力增压原理，开发一套具有射流式井底增压装置（DPS-1）和新型双流道高效破岩钻头（DCB-1）。创新点包括：开创了超高压水力与PDC机械联合高效破岩理论；研究开发了一套具有射流式井底增压装置；研究开发了一种新型双流道高效破岩PDC钻头。在温5—212井进行了现场试验，井段465.56～814.49m，进尺348.93m，纯钻11．33h，机械钻速30．79m／h，与同区块同井段牙轮钻头同比，机械钻速提高72．11％，钻头出口压力为70MPa。所以该技术是一个极富挑战性和可以充分发挥创造性的研究领域，这种技术潜在的经济效益是巨大的，也是目前可能有较大突破的一种联合破岩方法。

In last ten years, the technique of breaking rock using high pressure jet stream in assist of machinery was seen as one of simply approaches to enhance drilling speed in hard formations and deep wells. The technology of ultra-high pressure jet stream in bottom hole means to develop a set of downhole supercharging device(DPS-1) and a new kind of high efficiency bit with two flow channels(DCB-1) in foundation of the principles of breaking rock by the combination of hydraulic power & machinery and hydraulic supercharging. The innovations of this paper include three points, one of which is developing the theory of high effect breaking rock in combination of ultra-high pressure and PDC machinery; the second of which is researching & developing a set of downhole supercharging device with jet stream; the final of which is developing a new kind of high efficiency bit with two flow channels. The field experiment in well Wen5-212 in the depth of 465.56-814.49m demonstrated that the footage was 348.93m, the actual drilling time was 11.33 hours, and the drilling speed was 30.79 m/h, and the discharge pressure of bit was 70MPa. So the technology is a domain that is rich of challenge and creativity, and the latent economic benefit is large, also the technology is the method of breaking rock which has a greater breakthrough at some probability.