免扩孔径向水平井钻管转向室内试验

Drill Pipe Bending Test within Casing in Radial Drilling

针对免扩孔径向水平井钻管经转向器后与地层干涉这一问题,设计了钻管转向试验台以及转向器样机,并对钻管通过转向器过程进行了室内试验,研究钻管弯曲转向后的截面变形、推进力的变化规律,并对钻管的校直情况进行了数据分析.结果表明:相同外径的钻管,通过转向器样机时,穿出校直段钻管的椭圆度与壁厚有关,壁厚越小的钻管,椭圆度越大,对于相同直径的钻管来说,壁厚越大,通过时的推进力越大.对于相同壁厚不同直径的钻管来说,直径越大的钻管其所需的推进力越大.

Aiming at the problem that drilling pipe interfered with the formation after bend ing through the whipstock in the non-reaming radial drilling, the drilling pipe testbed and the whips tock proto type has been designed for drill pipe bending in the laboratory experiments. The section deformation of drill pipe after bending and propulsion variation regularity were researched and the straightening data on drill pipe has been analyzed. The results show that: For the drill pipe with the same outer diameter, the ellipticity of the straightening drill pipe section is related to the wall thickness of drill pipe, the smaller wall thickness, the larger ellip- ticity, the bigger wall thickness, the greater propulsion when the drill pipe bending through the whipstock. For the same wall thickness and different diameter drill pipe, the larger the diameter of the drill pipe which needs the greater propulsion.