Tools and technology of radical and level drilling/well completion under ultra-short radius

摘要

A system of components and a method is provided for radial and level drilling and completion with an ultra-short radius which includes a deflecting drill tool assembly and a level drill tool assembly. The deflecting drill tool has a deflecting rotary assembly, flexible drill pipe, directional follow-up tube, tail tube for deflecting drill tool, and drill pipe nipple joints. The level tool has a level rotary assembly, the flexible drill pipe, quick couplings, the directional follow-up tube, a tail tube for level drill tool, the drill pipe nipple joint, an adjusting nipple joint, a recessed left hand thread bushing, and convex left hand thread coupling. A triangle backing block is installed on outside of a casing of the deflecting rotary assembly. Splines matched with each other are provided at the level rotary assembly and the flexible drill pipe. The tail tube for level drill tool has a recessed left hand thread bushing and convex left hand thread coupling. A body of an inner ball is situated in a ball bowl and in frontal part of the main body of the flexible drill pipe and any single section of the flexible drill pipe may bend 3°-6°.