Lateral liner tie back system and method

A method for completing an existing liner positioned in a lateral bore, comprising the steps of:

• a) providing a lateral liner tie back system comprising:
• a junction sub having an outer wall enclosing a central bore, an opening through said outer wall, and a key affixed to said outer wall adjacent to said opening;
• a base sub having a central bore extending therethrough and a tapered upper end surface;
• and a tie back sub having a first outer wall, a tapered second outer wall, an interconnecting shoulder, a central bore enclosed by said first outer wall and said tapered second outer wall, and a series of threads extending along a circumference of said tapered second outer wall;
• b) positioning said base sub within a main bore directly below a window to a lateral bore such that said tapered upper end surface of said base sub is aligned with said lateral bore, wherein said lateral bore connects to said main bore through said window;
• c) positioning said junction sub through said window to said lateral bore such that said key of said junction sub engages said tapered upper end surface of said base sub thereby aligning said opening of said junction sub with said tapered upper end surface of said base sub;
• d) positioning said tie back sub within said central bore of said junction sub such that said tie back sub is adjacent to an upper end of an existing liner disposed within said lateral bore;
• and
• e) engaging said upper end of said existing liner with said series of threads on said tapered second outer wall of said tie back sub.