Currently Canada's casing drilling technology and VSM shaker technology are playing a leading role in the world, it has basically formed a distinctive casing drilling equipment and technology, and goes into industrial application stage and achieves good effect. In order to adapt wire rope from the drilling operations, casing drilling dedicated equipped with the open split crane, traveling block and wire rope BOP and seals installation. During drilling, the sleeve is used to transmit torque, but if the sleeve is passed directly, it may cause damage to the threaded sleeve. Therefore, between the top drive output shaft and casing string provide with a casing drive head. Cannula connected directly to the drive head, clap from the inner, drilling rig’s torque transmitted from top drive shaft to drive casing head, , and then spread to the casing from the head, casing threaded does not participate in the torque transmission. Casing drive head has drill, passing the torque and sealed circulating drilling fluid functions.
Suitable for casing drilling downhole drilling system, mainly contains 3 parts: downhole / recovery workers, with a bottom hole assembly, and connected to the bottom of the casing string at the end of the sleeve to sit. Currently, Canada has developed six sizes of downhole drilling systems: 339.7mm, 224.5mm, 193.7mm, 177.8mm, 139.7mm, 14.3mm. he casing drilling tools used in downhole recovery, including locking fishing spear, shock, measuring barrels, heavier rods for the centralizer, the upper tension buffer, rotate short section, and a short section of the emergency release cable plugs.
Bottom hole assembly use wire rope, generally contains lock and seal, separated hoop, floating drilling hoop, reaming and drill collar. Sitting bottom located in the end of the casing string, it compose by the centralizer axial locking short section (short sleeve lock section), a short section of the locking torque (torque tube short section), as well as positioning the shoulder, positioning stopper positioning trough. When is drilling, bottom hole assembly is locked in lock sitting on the end of a short section of casing. Special drill bit can be completely drilled out routine drill, and because there is a float collar as part of the casing string with downhole, cementing operations can be performed immediately after drilling to a depth of design, the full realization of the trip drilling completed drilling, cementing and other operations.
Has an important role for saving time and reducing operating costs. Across the globe, in 200 times field application, the casing drilling system’s success rate is 99%, well drilling segment construction is smooth, casing size from the largest 508.0mm to the smallest 114.3mm. Domestic oilfields conducted studies on drilling technology that do not need to change Domestic oilfields conducted studies do not replace the drill casing drilling technology. Established a way to adapt to the turntable drive shallow drilling development wells casing drilling tools supporting systems, Solve the problem of onshore oil domestic in the implementation of equipment conditions. China Development Research Institute of Petroleum Exploration and Development develop the suitable for casing drilling methods casing driver and drill threw hand.