FLOAT VALVE ASSEMBLY FOR DOWNHOLE TUBULARS

摘要

A check valve assembly for the bottom of a casing string with increased open area is provided. Multiple check valves are provided are provided for assurance of ultimate closure. Bypass flow paths are available during run in that increase the normal available open area from about 3 square inches to a rang e of about 10 square inches and even higher. Components freely float during run in to provide the greater open area and are subsequently repositioned with known technique s of dropping a ball and pressurization when the casing has reached the desired depth.