Patent ID: 9010425
Filing Date: 2015-04-21
Classification: E21B

Abstract:
1. A method for combined cleaning of an annulus in a well across a longitudinal section of the well, and subsequent plugging of the longitudinal section, said annulus being located outside a casing in the well, wherein the method, for such combined cleaning and plugging, comprises: (A) conducting a perforation tool into the casing to said longitudinal section of the well; (B) with the perforation tool, forming holes in the casing along the longitudinal section; (C) with a washing tool attached to a lower portion of a flow-through tubular work string and conducted into the casing to the longitudinal section, pumping a washing fluid down through the tubular work string and out into the casing via the washing tool; (D) with a directional means associated with the washing tool, conducting the washing fluid radially outward into the annulus via at least one hole formed in the casing at a first location within the longitudinal section, after which the washing fluid will flow via the annulus and onward into the casing via at least one hole formed therein in at least one second location within the longitudinal section and also moving the tubular work string and the washing tool within the longitudinal section while the washing fluid flows radially outward via said at least one hole in the casing, thereby cleaning the annulus; (E) thereafter pumping a fluidized plugging material from surface and down through the tubular work string and out into the casing at the longitudinal section; and (F) placing the fluidized plugging material in the casing, hence also in the annulus via said holes in the casing, along at least said longitudinal section of the well so that both the casing and said annulus is plugged along at least said longitudinal section of the well.