Casing strings and methods of using such strings in subterranean cementing operations

A method of cementing a pipe string in a subterranean formation, comprising:

• providing a well bore having a first fluid disposed therein;
• placing a second fluid into the well bore so as to displace at least a portion of the first fluid therefrom, the second fluid comprising a hydraulic settable component;
• placing in the well bore a pipe string having at least one activator encapsulated in an activator-encapsulant and disposed adjacent an outer surface thereof;
• permitting the second fluid and the activator to contact each other;
• and
• permitting the second fluid to set in the well bore;
• wherein providing a pipe string comprising an activator on an outer surface of the pipe string further comprises affixing the activator to a first side of a substrate having two sides, and affixing the second side of the substrate to the outer surface of the pipe string;
• and
• wherein the activator-encapsulant comprises a thermoplastic material.

A method of cementing a pipe string in a subterranean formation, comprising:

• providing a well bore having a first fluid disposed therein;
• placing a second fluid into the well bore so as to displace at least a portion of the first fluid therefrom, wherein the second fluid is a fluid comprising a hydraulic cement, a set retarder, and an invert emulsion comprising oil, water, and an emulsifying agent or a fluid comprising hydraulic settable component, a gel strength inhibiting agent, a set retarder, and a water source;
• providing a pipe string having at least one activator disposed adjacent an outer surface thereof;
• placing the pipe string in the well bore;
• permitting the second fluid and the activator to contact each other;
• permitting the second fluid to set in the well bore;
• and
• placing a cement composition into the well bore to displace at least a portion of the second fluid therefrom, wherein placing a cement composition into the well bore to displace at least a portion of the second fluid therefrom is performed before permitting the second fluid to set in the well bore.

A method of cementing a pipe string in a well bore, comprising:

• placing a well fluid comprising a hydraulic settable component into the well bore;
• placing in the well bore a pipe string having a cement-composition-activator and a well-fluid-activator disposed on an outer surface thereof;
• placing a cement composition in the well bore;
• permitting the cement composition and the cement-composition-activator to contact each other;
• permitting the well fluid and the well-fluid-activator to contact each other;
• permitting the cement composition to set in the well bore;
• and
• permitting the well fluid to set in the well bore.