Patent ID: 9284821
Filing Date: 2016-03-15
CPC Classification: E21B

Claim Text:
1. A method of forming a junction between wellbores, said method comprising the steps of: a) enlarging a length of a first wellbore to form an enlarged wellbore segment; b) installing casing in said first wellbore and in said enlarged wellbore segment; c) pumping material into said enlarged wellbore segment and allowing said material to harden to form a hardened material; d) reestablishing said first wellbore; e) forming a second wellbore by drilling out a lateral passage through said casing and said hardened material; f) positioning a liner in said second wellbore with an end of said liner covered with a swellable elastomer being disposed in said lateral passage; and g) allowing said swellable elastomer to expand and seal against the surface of said lateral passage in direct contact with said casing, said hardened material, and said formation, forming a sealed junction between said first wellbore and said second wellbore.