Temporary plug system

Abstract

A method and apparatus for establishing a fluid plug within a well bore which can then be substantially destroyed upon demand to permit reestablishment of the well within a short period of time thereafter. Increased pressure actuates a plug rupture mechanism which destroys the integrity of the plug and allows the plug to be substantially eliminated from the wellbore within a short period of time thereafter. In described preferred embodiments, the plug is comprised of a salt and sand mixture which is highly resistant to fluid compressive forces but is subject to destruction under shear tension forces. The plug may be encased within a plug sleeve which is, in turn, encased within a plug housing which may be disposed within the well bore. The sleeve is associated within the housing so that fluid may be displaced about the plug sleeve as the housing is disposed into the well bore. When the plug has reached the proper position within the well bore, the plug sleeve may be set within the housing such that fluid flow is stopped. A shear member is contained within the plug sleeve and detachably connected thereto. When required, the shear member may be released from the surrounding plug sleeve and forced against the plug to substantially destroy the integrity of the plug through introduction of shear tension forces within the plug structure and reestablish fluid flow through the housing. The plug is further dissolved into well bore fluids to substantially destroy it.