US 6,186,236 B1 · Multi-zone screenless well fracturing method and apparatus

Abstract

A multi-zone screenless well fracturing method and apparatus which allows multiple zones in a well to be treated with one trip of the apparatus into the hole. The apparatus includes a tool string generally comprising a crossover, a packer below the crossover, and a concentric wash pipe extending below the packer. The crossover has a first portion in communication with a tubing string connected thereto and a second portion in communication with a well annulus above the packer. The first portion of the crossover is in communication with the inner wash pipe, and the second portion of the crossover is in communication with the outer wash pipe. The tool string is adapted to stab through a plurality of big bore casing packers which are positioned between adjacent zones. A method of fracturing multiple zones in a well while monitoring conditions at the zone is also disclosed.

Claims20

Dependent claims

A method of fracturing a plurality of zones in a well comprising the steps of:

(a) closing the well below a first one of the zones;
(b) positioning a first casing packer between the first zone and a second zone;
(c) positioning a second casing packer above the second zone;
(d) providing a tool assembly comprising:
a tool packer;
a crossover positioned above said tool packer;
and
a concentric wash pipe positioned below said tool packer and having an inner wash pipe portion and an outer wash pipe portion;
(e) positioning said tool assembly through said first and second casing packers such that a lower end of said tool assembly is adjacent to the first zone;
(f) fracturing the first zone by pumping fracturing fluid through said tool assembly and monitoring progress of the fracturing operation at the surface;
(g) repositioning said tool assembly such that a lower end of said tool assembly is adjacent to the second zone;
and
(h) fracturing the second zone by pumping fracturing fluid through said tool assembly and monitoring progress of the fracturing operation at the surface.

10 more elements

A method of fracturing multiple zones in a well comprising the steps of:

(a) closing the well below a lower one of the zones;
(b) positioning a casing packer between adjacent zones;
(c) providing a downhole tool comprising:
a tubing string;
a crossover attached to said tubing string and having a central opening in communication with said tubing string and an outer portion in communication with a well annulus;
a tool packer attached to said crossover;
and
a concentric wash pipe disposed below said tool packer and having an inner wash pipe portion in communication with said central opening in said crossover and an outer wash pipe portion in communication with said outer portion of said crossover;
(d) positioning said downhole tool through said casing packer such that a lower end of said tool is below said casing packer;
(e) setting said tool packer;
and
(f) fracturing a zone below said casing packer by pumping fracturing fluid downwardly through said tubing string, said central opening of said crossover, said tool packer and said inner wash pipe portion and monitoring the fracturing operation by flowing fluid upwardly through said outer wash pipe portion, said tool packer, said outer portion of said crossover and the well annulus.

9 more elements

Dependencies are inferred from the claim text.

Multi-zone screenless well fracturing method and apparatus

Life of this patent

Multi-zone screenless well fracturing method and apparatus

Life of this patent

Abstract

Claims20