Casing strings and methods of using such strings in subterranean cementing operations
Improved casing strings, and methods of using improved casing strings in subterranean cementing operations, are provided. An example of an apparatus is a pipe string comprising at least one pipe section and a delivery system of an activator. Another example of an apparatus is a pipe string comprising at least one pipe section and a delivery system of a set retarder. An example of a method is a method of cementing in a subterranean formation. Other examples of methods are methods of cementing in a subterranean formation comprising a well bore.
1. A method of cementing in a subterranean formation, comprising:
placing a cement composition comprising a base fluid, a cement, and a set retarder in a subterranean formation;
providing a pipe string comprising an activator disposed adjacent an outer surface of the pipe string;
placing the pipe string into the subterranean formation;
allowing the cement composition to be activated by the activator; and
permitting the cement composition to set in the subterranean formation,
wherein the activator is an amine compound.
2. A method of cementing in a subterranean formation, comprising:
placing a cement composition comprising a base fluid, a cement, and a set retarder in a subterranean formation;
providing a pipe string comprising an activator disposed adjacent an outer surface of the pipe string;
placing the pipe string into the subterranean formation;
allowing the cement composition to be activated by the activator; and
permitting the cement composition to set in the subterranean formation,
wherein the activator is triethanol amine, diethanol amine, tripropanolamine, tri-isopropanolamine, or a mixture thereof.
3. A method of cementing in a subterranean formation, comprising:
placing a cement composition comprising a base fluid, a cement, and a set retarder in a subterranean formation;
providing a pipe string comprising an activator disposed adjacent an outer surface of the pipe string;
placing the pipe string into the subterranean formation;
allowing the cement composition to be activated by the activator; and
permitting the cement composition to set in the subterranean formation, wherein:
the pipe string has an inner diameter and an inner surface; and
a set retarder is disposed on the inner surface.
4. The method of claim 3 , wherein permitting the cement composition to set in the subterranean formation does not comprise permitting the cement composition to set in the inner diameter of the pipe string.