Multiple-set downhole tool and method

A multiple-set downhole tool assembly for selectively positioning within a well bore while suspended from a tubing string having a passageway, the downhole tool assembly adapted to be activated in the well bore by lowering a closure member having a selectively sized diameter through the tubing string to plug the passageway and thereafter pressurizing fluid in the passageway above the closure member, the downhole tool assembly comprising:

• body means defining at least in part an expandable and retractable fluid chamber;
• control sub means having an interior guide wall, a recessed cavity radially outward of the guide wall, and a flow path in pressure communication with the fluid chamber whereby the fluid chamber may be expanded by fluid pressure in the flow path in the control sub means;
• sleeve means axially movable within the control sub means from a closure stop position to a closure release position, the sleeve means having an interior surface having a diameter larger than the selectively sized diameter of the closure member, and having a port for fluid communication between the passageway in the tubing string and the flow path in the control sub means when the sleeve means is in the closure stop position;
• seal means for automatically closing off communication between the passageway in the tubing string and the flow path in the control sub means when sleeve means is in the closure release position;
• and
• stop means carried by the sleeve means and radially movable from an inward position such that the closure member is axially stopped by the stop means within the interior surface of the sleeve means, to an outward position such that the closure member may be passed axially by the sleeve means and the stop means;
• the stop means being restricted from radially outward movement to its outward position by the control sub means when the sleeve means is axially in the closure stop position, and the stop means being movable radially outward into the recessed cavity within the control sub means when the sleeve means is axially in the closure release position, whereby the closure member may be lowered into engagement with the stop means when the sleeve means is in the closure stop position, pressurized fluid in the passageway above the closure member passed through the port in the sleeve means and the flow path in the control sub means for activating the downhole tool assembly, and the sleeve means thereafter moved to the closure release position to seal pressurized fluid in the body means and permit the closure member to pass by the stop means as the stop means is positioned radially outward into the recessed cavity.

A method of activating a downhole tool assembly positioned in a well bore while suspended from a tubing string having a passageway, the downhole tool assembly including an expandable and retractable fluid chamber, and a control sub secured to a tool body and having a flow path in pressure communication with the fluid chamber, whereby the fluid chamber may be expanded by blocking the passageway with a closure member and increasing fluid pressure in the tubing string for transmission to the fluid chamber through the control sub flow path, the method comprising:

• providing an axially movable sleeve within the control sub movable between a closure stop position and a closure release position, the sleeve having an interior surface having a selectively sized diameter slightly larger than the diameter of the closure member, and a port for pressure communication between the passageway in the tubing string and the flow path in the control sub when the sleeve is in the closure stop position:
• providing a stop member carried by the sleeve and radially movable from an inward position such that the closure member is axially stopped within the sleeve by the stop member to an outward position such that the closure member may pass axially by the stop member;
• restricting the stop member from radial movement to the outward position when the sleeve is axially in the closure stop position;
• lowering the closure member through the tubular string to engage the stop member while the sleeve is in the closure stop position;
• increasing fluid pressure in the passageway above the closure member within the tubular string when the sleeve is in the closure stop position to activate the downhole tool assembly in the well bore;
• closing off communication between the passageway in the tubular string and the flow path in the control sub when the sleeve is in the closure release position;
• and
• moving in the sleeve axially to the closure release position and the stop member radially to its outward position while simultaneously sealing fluid within the flow path of the control sub to maintain the downhole tool assembly in the activated position.