Fremgangsmåte og anordning for forbindelse av en sideforgrening av et forlengingsrör til et hovedborehull

A method and apparatus for establishing connectivity of lateral branch liners to main well casings to achieve predictable and stable mechanical connectivity at the lateral junction of branch well bores to the main well bore to counter the problems of formation instability at the junction. After construction of a well having one or more lateral branches, a retrievable lateral branch template is located in the casing of a main well bore in positioned and oriented registry with a casing window that opens to a lined lateral branch. A retrievable lateral branch connector is then installed in assembly with the template to cooperatively define a production flow path having maximized mechanical integrity and optimized production flow in both the lateral bore and the main bore. The lateral branch template and connector provide the capability to selectively re-enter a lateral branch and to also hydraulically isolate the formation surrounding the junction from fluid circulating in both the lateral branch and the main well bore. Both the lateral branch template and the lateral branch connector are prefabricated and installed into the well by means of running and setting tools. Electrical power or hydraulic pressure conductors incorporated in the template and connector assembly may be used to provide for production operation and control of main and branch well bore production after installation. The equipment can be deployed in wells constructed with any inclination and orientation and can accommodate low or high dogleg severity at kick-off.