Method and tool for directing an annular flow across a well bore interval

An isolating tool for selectively orienting a flow of a well fluid with respect to a demarcation in an annulus of a well bore, the annulus defined by a production tubing inside the well bore, the tool attachable to a downhole end of the production tubing injecting or receiving the well fluid, the tool comprising:

• a cylindrical tool housing having a top end conductively connectable to the production tubing and a bottom end opposite the top end;
• a lower cylindrical element spring-positioned within and slidably sealing an exterior of the element against an interior wall of the tool housing, the element having an element bore narrowing toward one end and conductive of the well fluid from the production tubing, the spring-positioning and the narrowing bore configured to compress the element toward the narrowing end of the element in proportion to an injection velocity of the well fluid;
• a lower expandable annular seal disposable on an exterior wall of the tool housing for restricting annular fluid flow across the demarcation;
• a lower compression means linked to the slidable element for expanding the lower seal against the well bore when the injection velocity of the well fluid exceeds a lower seal threshold;
• and
• where exceeding the lower seal threshold enables a treatment of a hydrocarbon production interval surrounding the well bore above the demarcation;
• an element downstream port connecting the bore to the element exterior below the seal, and an annular downstream passage in the housing, the port and the passage slidably alignable for annular downstream flow from the bore when the injection velocity falls below a downstream flow threshold, thereby closing off the bottom end at higher velocities.

An isolating tool for selectively orienting a flow of a well fluid with respect to a demarcation in an annulus of a well bore, the annulus defined by a production tubing inside the well bore, the tool attachable to a downhole end of the production tubing injecting or receiving the well fluid, the tool comprising:

• a cylindrical tool housing having a top end conductively connectable to the production tubing and a bottom end opposite the top end;
• a lower cylindrical element spring-positioned within and slidably sealing an exterior of the element against an interior wall of the tool housing, the element having an element bore narrowing toward one end and conductive of the well fluid from the production tubing, the spring-positioning and the narrowing bore configured to compress the element toward the narrowing end of the element in proportion to an injection velocity of the well fluid;
• a lower expandable annular seal disposable on an exterior wall of the tool housing for restricting annular fluid flow across the demarcation;
• a lower compression means linked to the slidable element for expanding the lower seal against the well bore when the injection velocity of the well fluid exceeds a lower seal threshold;
• and
• where exceeding the lower seal threshold enables a treatment of a hydrocarbon production interval surrounding the well bore above the demarcation;
• an upper slidable element spring-positioned within the tool housing and upstream of the lower slidable element, the element configured with a narrowing bore for compression toward its narrowing end in proportion to the injection velocity, an upper compression means linked to the upper element for expanding an upper annular seal against the well bore when the injection velocity exceeds an upper seal threshold, the lower and the upper slidable elements for isolating and pressurizing the production interval through a perforation cluster in the well bore;
• an element upstream port connecting the bore of the lower slidable element to the element exterior above the lower seal, and an annular upstream passage in the housing, the upstream port and the upstream passage slidably alignable for an annular upstream flow from the bore when the injection velocity exceeds an upstream flow threshold, and
• an element downstream port connecting the bore of the lower slidable element to the element exterior below the lower seal, and an annular downstream passage in the housing, the downstream port and the downstream passage slidably alignable for an annular downstream flow from the bore when the injection velocity falls below a downstream flow threshold.

An isolating tool for selectively orienting a flow of a well fluid with respect to two demarcations bracketing a fracture zone of a well bore, the tool attachable to a lower end of a production tubing injecting or receiving the well fluid, the production tubing inside the well bore defining an annulus, the tool comprising:

• a cylindrical tool housing having a top end conductively connectable to the production tubing and a bottom end opposite the top end;
• a lower and an upper cylindrical element slidingly positioned within and near opposite ends of the tool housing, where each of the elements:
• is spring-positioned with an element exterior sealing against an interior wall of the tool housing,
• includes an element bore narrowing toward one end and conductive of the well fluid from the production tubing, and
• is configured to compress the element toward the narrowing end in proportion to an injection velocity of the well fluid by adjusting the spring positioning and bore dimensions;
• a lower and an upper annular seal each disposable on an exterior wall of the tool housing at the lower and the upper demarcations, respectively, for restricting fluid flow across the annulus;
• a lower and an upper compression means linked respectively to the lower and the upper slidable elements for expanding the lower seal against the well bore when the injection velocity exceeds a lower seal threshold and for expanding the upper seal against the well bore when the injection velocity exceeds an upper seal threshold;
• where an injection velocity exceeding the upper and the lower seal thresholds seals the annulus at both demarcations for treating the fracture zone;
• and
• the upper and the lower annular seals each further comprise:
• a conical collar disposable around the housing exterior at the respective well bore demarcation and axially sloping outward in a direction of seal compression;
• a cylindrical flexure sleeve formed of multiple tines ringed at one end to receive pressure from the respective compression means during fluid injection, the multiple tines free floating at the other end for slidable expansion over the conical collar;
• a rubber overmolding substantially wrapping the flexure sleeve and expandable at the respective demarcation when acted upon by the respective slidable element;
• and
• where an injection velocity exceeding the upper and the lower seal thresholds expands the rubber overmoldings to seal the annulus at both demarcations for treating the fracture zone.

An isolating tool for selectively orienting a flow of a well fluid with respect to two demarcations bracketing a fracture zone of a well bore, the tool attachable to a lower end of a production tubing injecting or receiving the well fluid, the production tubing inside the well bore defining an annulus, the tool comprising:

• a cylindrical tool housing having a top end conductively connectable to the production tubing and a bottom end opposite the top end;
• a lower and an upper cylindrical element slidingly positioned within and near opposite ends of the tool housing, where each of the elements:
• is spring-positioned with an element exterior sealing against an interior wall of the tool housing,
• includes an element bore narrowing toward one end and conductive of the well fluid from the production tubing, and
• is configured to compress the element toward the narrowing end in proportion to an injection velocity of the well fluid by adjusting the spring positioning and bore dimensions;
• a lower and an upper annular seal each disposable on an exterior wall of the tool housing at the lower and the upper demarcations, respectively, for restricting fluid flow across the annulus;
• a lower and an upper compression means linked respectively to the lower and the upper slidable elements for expanding the lower seal against the well bore when the injection velocity exceeds a lower seal threshold and for expanding the upper seal against the well bore when the injection velocity exceeds an upper seal threshold;
• where an injection velocity exceeding the upper and the lower seal thresholds seals the annulus at both demarcations for treating the fracture zone;
• and
• the element bore of one of the upper and the lower slidable element narrows toward the top end of the housing for compressing the element in a direction opposite to that of the injection velocity.

An isolating tool for selectively orienting a flow of a well fluid with respect to two demarcations bracketing a fracture zone of a well bore, the tool attachable to a lower end of a production tubing injecting or receiving the well fluid, the production tubing inside the well bore defining an annulus, the tool comprising:

• a cylindrical tool housing having a top end conductively connectable to the production tubing and a bottom end opposite the top end;
• a lower and an upper cylindrical element slidingly positioned within and near opposite ends of the tool housing, where each of the elements:
• is spring-positioned with an element exterior sealing against an interior wall of the tool housing,
• includes an element bore narrowing toward one end and conductive of the well fluid from the production tubing, and
• is configured to compress the element toward the narrowing end in proportion to an injection velocity of the well fluid by adjusting the spring positioning and bore dimensions;
• a lower and an upper annular seal each disposable on an exterior wall of the tool housing at the lower and the upper demarcations, respectively, for restricting fluid flow across the annulus;
• a lower and an upper compression means linked respectively to the lower and the upper slidable elements for expanding the lower seal against the well bore when the injection velocity exceeds a lower seal threshold and for expanding the upper seal against the well bore when the injection velocity exceeds an upper seal threshold;
• where an injection velocity exceeding the upper and the lower seal thresholds seals the annulus at both demarcations for treating the fracture zone;
• and
• an axial bypass downstream of the lower annular seal for closing tubular outflow therefrom and for pressurizing the fracture zone, the axial bypass comprising a conical plug closing off the center of a bottom end of the lower slidable element, a drain gating a central portion of the bottom end of the tool housing and sealingly receivable of the conical plug when the injection velocity is greater than a bypass threshold, and one or more plug vents around the central portion for passing well fluids when the axial bypass is open.

An isolating tool for selectively orienting a flow of a well fluid with respect to two demarcations bracketing a fracture zone of a well bore, the tool attachable to a lower end of a production tubing injecting or receiving the well fluid, the production tubing inside the well bore defining an annulus, the tool comprising:

• a cylindrical tool housing having a top end conductively connectable to the production tubing and a bottom end opposite the top end;
• a lower and an upper cylindrical element slidingly positioned within and near opposite ends of the tool housing, where each of the elements:
• is spring-positioned with an element exterior sealing against an interior wall of the tool housing,
• includes an element bore narrowing toward one end and conductive of the well fluid from the production tubing, and
• is configured to compress the element toward the narrowing end in proportion to an injection velocity of the well fluid by adjusting the spring positioning and bore dimensions;
• a lower and an upper annular seal each disposable on an exterior wall of the tool housing at the lower and the upper demarcations, respectively, for restricting fluid flow across the annulus;
• a lower and an upper compression means linked respectively to the lower and the upper slidable elements for expanding the lower seal against the well bore when the injection velocity exceeds a lower seal threshold and for expanding the upper seal against the well bore when the injection velocity exceeds an upper seal threshold;
• where an injection velocity exceeding the upper and the lower seal thresholds seals the annulus at both demarcations for treating the fracture zone;
• and
• an element upstream port connecting the bore of the lower slidable element to the element exterior above the lower seal, and an annular upstream passage in the housing, the upstream port and the upstream passage slidably alignable for an annular upstream flow from the bore when the injection velocity exceeds an upstream flow threshold and the bottom end of the housing is closed.

A method for treating an isolated hydrocarbon interval of a well bore feedable by a well fluid through a production tubing inside the well bore, the well bore and the production tubing forming an annulus therebetween, the method comprising:

• attaching to the production tubing a perforated cylindrical housing disposed with an expandable annular seal and an internal element slidable within the housing, the slidable element mechanically linked to actuate the annular seal and positionally responsive to an injection velocity of the well fluid and positioned by a spring;
• lowering the cylindrical housing to a sealing depth for bracketing a perforation cluster in the well bore for the corresponding hydrocarbon interval;
• injecting the well fluid and selecting an injection velocity sufficient to drag the slidable element downward for expanding the annular seal against the well bore, the drag induced by an element bore conically narrowing toward a lower end of the element;
• and
• directing an annular flow downstream or upstream of the expandable seal by either setting a downstream injection velocity to slidably align an element downstream port with a corresponding housing perforation, or setting an upstream injection velocity exclusively different from the downstream injection velocity in order to slidably align an element upstream port with a corresponding housing perforation.