Method and apparatus for stimulating hydrocarbon wells
DCFirst Claim
1. A downhole tool, comprising;
- a body having a recess formed therein, the recess adapted to receive a pivotable valve member having at least one concave surface;
a valve seat disposed within the body; and
a shiftable sleeve disposed within the body,wherein the sleeve, in a first position, is adapted to contain the pivotable valve member within the recess and seal the recess against entry of debris, and the sleeve, in a second position, is adapted to release the pivotable valve member allowing the pivotable member to engage the valve seat, wherein an end of the sleeve is adapted to sealingly engage the valve seat, andwherein the valve seat has an O-ring disposed thereon and the end of the sleeve is adapted to seal against the O-ring.
3 Assignments
Litigations
0 Petitions
Accused Products
Abstract
One or more flapper valve assemblies are placed in a casing string extending through one or more hydrocarbon bearing intervals. The flapper valve assemblies are placed between some of the hydrocarbon bearing intervals. In an open or inoperative position, the flapper valve assemblies are full opening compared to the casing string. The hydrocarbon bearing intervals are stimulated, typically by fracing, starting with the bottom zone. The flapper valve assembly immediately above the stimulated interval is manipulated to allow it to close, preventing downward flow in the well and thereby isolating the lower stimulated interval so an upper interval can be stimulated. The well is easy to put on production because the flapper valves will normally open simply by opening the well at the surface.
56 Citations
19 Claims
-
1. A downhole tool, comprising;
-
a body having a recess formed therein, the recess adapted to receive a pivotable valve member having at least one concave surface; a valve seat disposed within the body; and a shiftable sleeve disposed within the body, wherein the sleeve, in a first position, is adapted to contain the pivotable valve member within the recess and seal the recess against entry of debris, and the sleeve, in a second position, is adapted to release the pivotable valve member allowing the pivotable member to engage the valve seat, wherein an end of the sleeve is adapted to sealingly engage the valve seat, and wherein the valve seat has an O-ring disposed thereon and the end of the sleeve is adapted to seal against the O-ring. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A bridge plug, comprising:
-
a body having a bore formed therethrough, an element system disposed about a first end of the body, a flapper valve assembly disposed within a second end of the body, the assembly comprising; a recess adapted to receive a pivotable valve member having at least one concave surface; a valve seat disposed within the body; and a shiftable sleeve disposed within the body, wherein the sleeve, in a first position, is adapted to contain the pivotable valve member within the recess and seal the recess against entry of debris, and the sleeve, in a second position, is adapted to release the pivotable valve member allowing the pivotable member to engage the valve seat, wherein an end of the sleeve is adapted to sealingly engage the valve seat. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A method for isolating a wellbore, comprising:
-
locating one or more tools within the wellbore, the one or more tools comprising; a body having a bore formed therethrough, an element system disposed about a first end of the body, a flapper valve assembly disposed within a second end of the body, the assembly comprising; a recess adapted to receive a pivotable valve member having at least one concave surface; a valve seat disposed within the body; and a shiftable sleeve disposed within the body, wherein the sleeve, in a first position, is adapted to contain the pivotable valve member within the recess and seal the recess against entry of debris, and the sleeve, in a second position, is adapted to release the pivotable valve member allowing the pivotable member to engage the valve seat, wherein an end of the sleeve is adapted to sealingly engage the valve seat; and expanding the element system to engage an inner surface of the wellbore thereby setting the tool within the wellbore. - View Dependent Claims (18, 19)
-
Specification