CPC E21B 33/14 (2013.01) [E21B 33/13 (2013.01); E21B 37/00 (2013.01); E21B 41/0078 (2013.01)] | 10 Claims |
1. A method of cementing an annulus exterior to a perforated region of casing in an oil or gas well to be abandoned, the method comprising:
a. delivering to the perforated region a cementing tool comprising a body in which at least one nozzle aperture is formed, the tool being delivered in a first configuration in which the body has a first outer diameter;
b. reconfiguring the tool such that the body has a second, larger, outer diameter, wherein the degree of expansion of the tool is limited such that the tool is designed to expand to a pre-set maximum diameter less than the diameter of the casing when pressurized so as to reduce the size of an annular region between the tool and the casing; and
c. delivering cement through the said at least one nozzle aperture into the annular region between the tool and the casing and then through perforations in the casing and into the exterior annulus.
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