Production Casing
Production casing is set through the prospective productive zones except in the case of open-hole completions. It is usually designed to hold the maximal shut-in pressure of the producing formations and may be designed to withstand stimulating pressures during completion and workover operations. It also provides protection for the environment in the event of failure of the tubing string during production operations and allows for the production tubing to be repaired and replaced.
Production casing varies from in. to 9| in. in diameter, and is cemented far enough above the producing formations to provide additional support for subsurface equipment and to prevent casing buckling.