In coiled tubing offshore re-entry drilling and workover operations, a jack-up pulling unit or an independent mast has traditionally been used to pull pipe out of the wellbore before the coiled tubing services could be employed. This method of operation often becomes cumbersome and costly. An innovative coiled tubing (CT) drilling system that offers an alternative method to the conventional techniques has been introduced to the oilfield. LTh new system, the hybrid coiled tubing system (HCTS), integrates the coiled tubing injector, the power unit and the reel into a transportable rig with a mast. The concept and design of the methods and equipment were developed to respond to the need for servicing shallow to moderate-depth oil or gas wells in teh Gulf of Mexico. In this area, typical well specifications range to 10,000 ft measured depth; and wells are usually directionall drilled from multiple-well, fixed paltform structures or in shallow inland waters. A specific case history is outlined to show the utility of using hybrid CT instead of a conventional rig for the type of work required. Operational efficiency and safety advantages are evident in mobilization, demobilization, speed of rig-up and rig-down, and in the reduction of time needed for tripping into and out of the well. This system provides a cost efficient solution to the need for a er-entry system for offshore use.
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