Patent ID: 6732797
Filing Date: 2004-05-11
Classification: E21B

Abstract:
A method of forming a mass of hardened cementitious material in a well bore penetrating the earth, said method being comprised of the steps of:selecting a well bore extending from the surface of said earth to at least one subterranean formation containing a well fluid, said well bore having communication means with said subterranean formation and having a static column of said well fluid standing therein, wherein the top of said column of said well fluid is positioned below said surface of said earth; introducing into said well bore at least a first cementing unit and permitting said first cementing unit to contact said top of said column of said well fluid, wherein said cementing unit is comprised of a first solid plug, a quantity of a first liquid comprised of said cementitious material dispersed in water, a second solid plug and a quantity of a second liquid, wherein said cementitious material has hydraulic activity; permitting said cementing unit to force said well fluid into said subterranean formation through said communication means while, simultaneously, placing said cementing unit in said well bore so that the bottom of said first liquid is positioned adjacent said subterranean formation and the top of said first liquid is positioned above the top of said subterranean formation; introducing into said well bore a final cementing unit which is comprised of a final solid plug and a final quantity of said first liquid whereby the top of said final quantity of said first liquid is positioned substantially at said surface of said earth; and permitting said first liquid to set to thereby form said mass of hardened cementitious material in said well bore; wherein said first solid plug, said second solid plug and said final solid plug are each in contact with and slide along the interior wall of said well bore and substantially prevent movement of liquid between each said solid plug and said interior wall of said well bore.