Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
257 words
The method of washing casing perforations and connected formation channels of a subterranean well comprising the steps of: (a) inserting an outer tubular body into the well on a tubing string, said outer tubular body having radial ports alignable with a selected set of casing perforations, an open bottom communicable with the casing bore, annular sealing elements engaging the well casing above and below the said radial ports, and a radial bypass port disposed above said annular sealing elements; (b) sealing the annulus between said outer tubular body and the casing above all casing perforations; (c) inserting an inner tubular body having an open bottom bore within the outer tubular body on a second tubular string, a continuous annular passage thereby being defined between said outer and inner tubular bodies and said outer and inner tubing strings, the bore area of said inner tubular body being substantially less than the area of the annular passage; (d) effecting a seal between the bottom end of said inner tubular body and the bore of said outer body at a position axially below said radial ports; (e) circulating washing fluid downwardly through said annular passage, thence outwardly through said radial ports and through said casing perforations and said formation channels, thence around the exterior of the casing, and thence upwardly through the casing bore and the interconnected bore of the inner tubular member and its tubing string to the surface of the well; and (f) maintaining said port open during step (a), and closing said bypass port during step (c).
Claim 2
Independent Claim
257 words
The method of washing casing perforations and connected formation channels of a subterranean well comprising the steps of: (a) inserting an outer tubular body into the well on a tubing string, said outer tubular body having radial ports alignable with a selected set of casing perforations, an open bottom communicable with the casing bore, annular sealing elements engaging the well casing above and below the said radial ports, and a radial bypass port disposed above said annular sealing elements; (b) sealing the annulus between said outer tubular body and the casing above all casing perforations; (c) inserting an inner tubular body having an open bottom bore within the outer tubular body on a second tubular string, a continuous annular passage thereby being defined between said outer and inner tubular bodies and said outer and inner tubing strings, the bore area of said inner tubular body being substantially less than the area of the annular passage; (d) effecting a seal between the bottom end of said inner tubular body and the bore of said outer body at a position axially below said radial ports; (e) circulating washing fluid downwardly through said annular passage, thence outwardly through said radial ports and through said casing perforations and said formation channels, thence around the exterior of the casing, and thence upwardly through the casing bore and the interconnected bore of the inner tubular member and its tubing string to the surface of the well; and (f) maintaining said port open during step (a), and closing said bypass port during step (c).
Claim 3
Dependent Claim
59 words
The method of claim 1 wherein said outer tubular body has radial bypass ports disposed above said annular sealing element and having an axially slidable valve positioned above said bypass ports during step (a), plus the step of moving said axially slidable valve downwardly to a closed position during the insertion of the inner tubular body in step (c).
Claim 4
Dependent Claim
46 words
The method of claim 2 plus the step of withdrawing the inner and outer tubular bodies from the well, the inner body being moved in advance of said outer tubular body to shift said axially slidable valve upwardly to its open position above said bypass ports.