METHOD OF ENHANCING DRILLING FLUID PERFORMANCE

摘要

The present invention relates to methods of drilling a wellbore wherein a drill-in fluid is foamed at the drill tool. A method in accordance with the present invention comprises providing a drill-in fluid comprising an aqueous fluid, a foaming agent, a foam stabilizer, a gas generating chemical and an encapsulated activator; introducing the drill-in fluid downhole into a drill string connected to a drill tool; and allowing the drill-in fluid to exit the drill tool where, upon exiting the drill tool, the encapsulated activator is de-capsulated sufficiently to react with the gas generating chemical such that a gas is generated within the drill-in fluid and thus foams the drill-in fluid.

主权项

1. A method of drilling in a wellbore comprising:
a. providing a drill-in fluid comprising an aqueous fluid, a foaming agent, a foam stabilizer, a gas generating chemical and an encapsulated activator; b. introducing said drill-in fluid downhole into a drill string connected to a drill tool wherein both said gas generating chemical and said encapsulated activator are admixed into said drill-in fluid prior to introduction into said drill string; and c. allowing said drill-in fluid to exit said drill tool where, upon exiting said drill tool, said encapsulated activator is de-capsulated sufficiently to react with said gas generating chemical such that a gas is generated within said drill-in fluid and thus foams said drill-in fluid.