US Patent 7779919 Flapper valve retention method and system

A system and method for use in a wellbore that includes a string comprising a housing. The housing comprises a valve including a valve seat having an inner channel and a flapper configured to pivot relative to the valve seat between a first position and a second position in which the inner channel is obstructed. A valve actuating device may be provided for selectively opening the valve and comprising a first hydraulic device. In addition, a retention device including a second hydraulic device may be provided and configured to selectively retain the flapper in the first position. In some cases, the first hydraulic device and the second hydraulic device may be driven by the same fluid source.