US 8,616,285 B2 · Step ratchet fracture window system

Abstract

The present invention is to an internal sleeve slidably received within a tubular housing. The sleeve and outer housing have windows that selectively align. Movement of the sleeve within the housing is controlled by a ball passing through the interior of the sleeve to activate a ratchet that allows the sleeve to move a set amount under the influence of a spring. A split seat at a lower end of the housing traps after a set number of balls have passed through the housing. A number of similar tools can be used to provide openings at various points that include coordinated ratchet steps so that only one tool at a time opens for fracturing or other purposes. A reverse flow causes a ball to impinge upon the next higher ball seat and thereby opening the seat to provide a full bore flow passage through the tool.

Claims20

Dependent claims

A downhole tool, comprising:

a cylindrical outer sleeve defining an axial bore therethrough and at least one lateral opening on the other circumference of the cylindrical outer sleeve;
an inner sleeve slidably disposed coaxially within the axial bore of the outer sleeve and defining an inner chamber and at least one lateral opening on the other circumference of the inner sleeve;
and
a ratchet mechanism disposed within the inner chamber of the inner sleeve and having a first position and a second position such that when the ratchet mechanism is in the first position the inner sleeve lateral opening is fluidly sealed from the outer sleeve lateral opening and when the ratchet mechanism is in the second position the inner sleeve lateral opening is in fluid communication with the outer sleeve at least one lateral opening.

1 more element

A method, comprising:

disposing an assembly downhole in a wellbore, the assembly comprising:
a set of tubing;
a plurality of downhole tools, interspersed along the tubing, each downhole tool comprising:
an outer housing defining an axial bore therethrough and at least one lateral opening;
an inner sleeve slidably disposed coaxially within the axial bore of the outer housing and defining an inner chamber and at least one lateral opening;
a ratchet mechanism disposed within inner chamber of the inner sleeve having as first position and a second position such that when the ratchet mechanism is in the first position the inner sleeve lateral opening is fluidly sealed from the outer housing lateral opening and when the ratchet mechanism is in the second position the inner sleeve lateral opening is in fluid communication with outer sleeve housing lateral opening;
and
a plurality of valve seats, each valve seat functionally associated with a respective one of the downhole tools;
wherein the downhole tools are configured to a closed position upon deployment and indexed to its respective position on the set of tubing relative to the rest of the downhole tools;
and
dropping a plurality of balls down the wellbore, each ball ratcheting each downhole tool through which it passes closer to an open position.

8 more elements

Dependencies are inferred from the claim text.

Step ratchet fracture window system

Life of this patent

Step ratchet fracture window system

Life of this patent

Abstract

Claims20