TUBING INJECTION SYSTEMS FOR LAND AND UNDER WATER USE

摘要

This invention provides a tubing injection system that contains an injector (200) with two movable injection blocks which are remotely operable to provide a desired opening. Each injection block contains a plurality of gripping members for holding a range of tubing sizes. The injection blocks automatically adjust to provide the required gripping force and tubing speed according to programmed instructions. A resilient tubing guidance system (40) is positioned above the injector head directs the tubing into the injector head. Sensors are provided to determine the radial force on the tubing exerted by the injector head, tubing speed, injector speed, compression of the tubing guidance member and the back tension on the reel. A control unit (170) continually maintains the tubing speed, tension and radial pressure on the tubing within predetermined limits. The control unit also maintains the back tension on the reel. This invention also provides a tubing handling system for moving a tubing from a vessel into a subsea wellbore. A main (200) injector of the type described above is permanently attached to the wellhead. A smaller injector (190) at the vessel moves the tubing from the vessel to the underwater injector. A riser (80) between the two injectors guides the tubing into the underwater injector. Acontrol unit (170) controls the operation of the system.