TELESCOPING LATCHING MECHANISM FOR CASING CEMENTING PLUG.

摘要

Improved cementing plugs and methods of using these cementing plugs in subterranean wells are disclosed. A cementing plug comprises a hollow mandrel and one or more wiper elements coupled to the mandrel. A nose is coupled to the hollow mandrel and is movable between a retracted position and an extended position. A portion of the nose is positioned within the mandrel when in the retracted position. This portion of the nose is positioned outside the mandrel when in the extended position.