US 7,743,824 B2 · Method and apparatus for isolating a wellhead for fracturing

Abstract

A wellhead assembly to seal to a production casing including one or more pressure-containing wellhead body members defining a vertical bore, with the lowermost of the wellhead body members sealing to the production casing. A fracturing isolation tool is sealed in the vertical bore of the wellhead body members above the production casing, and forms a pressure barrier profile in its internal bore. A removable protector sleeve is located at least partially within the fracturing isolation tool to seal, protect, isolate and cover the pressure barrier profile against a fracturing pressure and a fracturing fluid. After fracturing the protector sleeve is removed and a pressure barrier is sealed in the pressure barrier profile of the fracturing isolation tool. The invention also extends to the method of isolating the wellhead body members and to the fracturing isolation tool assembly which includes the fracturing isolation tool and the protector sleeve.

Claims21

Dependent claims

A wellhead assembly which seals to a production casing, comprising:

one or more pressure-containing wellhead body members defining a vertical bore extending there through, the lowermost end of the one or more wellhead body members being adapted to seal to the production casing;
a fracturing isolation tool sealed in the vertical bore of the one or more wellhead body members above the production casing, and forming an internal bore extending vertically there through,
a pressure barrier profile formed in the internal bore of the fracturing isolation tool to accommodate a pressure barrier;
and
a removable protector sleeve located at least partially within the fracturing isolation tool to seal, protect, isolate and cover the pressure barrier profile against a fracturing pressure and a fracturing fluid, the protector sleeve forming an internal bore extending vertically there through.

2 more elements

A method of isolating one or more wellhead members for fracturing, comprising:

providing one or more pressure-containing wellhead body members defining a vertical bore extending there through to communicate with the production casing, the lowermost end of the one or more wellhead body members being adapted to seal to the production casing;
locating a fracturing isolation tool in sealing relationship in the vertical bore of the one or more wellhead body members above the production casing, the fracturing isolation tool forming an internal bore extending vertically there through, and having a pressure barrier profile formed in the internal bore to accommodate a pressure barrier;
locating a removable protector sleeve at least partially within the fracturing isolation tool to seal, protect, isolate and cover the pressure barrier profile against a fracturing pressure and a fracturing fluid, the protector sleeve forming an internal bore extending vertically there through;
such that, when the fracturing isolation tool and the protector sleeve are sealed in the vertical bore, all seals and openings in the one or more wellhead body members are protected from a fracturing pressure and a fracturing fluid.

1 more element

Dependencies are inferred from the claim text.

Method and apparatus for isolating a wellhead for fracturing

Life of this patent

Method and apparatus for isolating a wellhead for fracturing

Life of this patent

Abstract

Claims21