METHOD AND APPARATUS FOR CONDUCTING EARTH BOREHOLE OPERATIONS USING COILED CASING

摘要

A method and apparatus for conducting earth borehole operations include a reel 28 of continuous coiled casing 30, and an injector 20 for moving the coiled casing. The bottomhole assembly including at least a motor 54 and a bit 56 is connected to the free end of the coiled casing, and injected into the earth while circulating fluid through the coiled casing to form a drilled earth borehole having a borehole wall. The coiled casing drill string may be retrieved from the borehole, the bottomhole assembly removed, and the coiled casing again injected into the borehole, then suspended from a wellhead assembly. After severing the coiled casing, a bonding agent such as a cementitious material may be injected into the suspended coiled casing and into the annulus between the coiled casing and the borehole.