A chemical reaction heat source for use in heaters used in down-hole applications is provided. The heat source has a fuel composition that comprises thermite and a damping agent. The use of the thermite mix enables the heaters of the present invention to generate hotter temperatures down wells. This in turn allows the use of Bismuth/Germanium alloys, which have higher melting points, to enable the production of plugs for the abandonment of deeper wells where subterranean temperatures are higher.

A chemical reaction heat source for use in heaters used in down-hole applications is provided. The heat source has a fuel composition that comprises thermite and a damping agent. The use of the thermite mix enables the heaters of the present invention to generate hotter temperatures down wells. This in turn allows the use of Bismuth/Germanium alloys, which have higher melting points, to enable the production of plugs for the abandonment of deeper wells where subterranean temperatures are higher.

This invention relates to a blast plug (10). The blast plug (10) includes a body (12), a means for suspending the blast plug (10) in a blast hole (50) above an explosive charge (54) and a bag member (16). The body (12) comprises a first end (18), an opposing second end (20) and one or more sides tapering (22) from the first end (18) towards the second end (20). The blast plug (10) suspending means is located at least partially at the second end (20) of the body (12). The bag member (16) is attached to the tapering sides (22) of the body (12) and extends about the body (12) such that the attached portion of the bag member (16) is restricted from moving toward the first end (18) of the body (12) by the tapering sides (22) thereof, wherein the bag member (16) operatively catches and contains tamping material deposited down the blast hole (50). In use, with the blast plug (10) suspended in the blast hole (50) by the blast plug (10) suspending means, the tamping material caught and contained in the bag member (16) causes the bag member (16) to expand radially outwardly relative to the body (12) to abut and seal against the blast hole walls (56) thereby to confine the blast energy generated on detonation of the explosive charge (54), with the first end (18) of the body (12) acting to reflect pressure waves propagating from the detonated explosive charge (54) back down the blast hole (50) thereby to increase the efficiency of the explosion.

A plug for plugging wells, and in particular oil and gas wells, is provided. The plug has a plug body formed from an outer metal tube of a reduced thickness. The plug also has reinforcement means, attached to an inner surface of the outer tube, that give the plug a cross-sectional structural strength that is at least equivalent to that of a thicker metal tube. The plug has a central heater receiving void located along the axis of the plug to enable a plug deployment heater to be received therein. Also provided is a plug assembly with a variable cross-sectional area in a plane perpendicular to the plane in which the assembly is deployed during the plugging of underground conduits.

A plug for plugging wells, and in particular oil and gas wells, is provided. The plug has a plug body formed from an outer metal tube of a reduced thickness. The plug also has reinforcement means, attached to an inner surface of the outer tube, that give the plug a cross-sectional structural strength that is at least equivalent to that of a thicker metal tube. The plug has a central heater receiving void located along the axis of the plug to enable a plug deployment heater to be received therein. Also provided is a plug assembly with a variable cross-sectional area in a plane perpendicular to the plane in which the assembly is deployed during the plugging of underground conduits.

A chemical reaction heat source for use in heaters used in down-hole applications is provided. The heat source has a fuel composition that comprises thermite and a damping agent. The use of the thermite mix enables the heaters of the present invention to generate hotter temperatures down wells. This in turn allows the use of Bismuth/Germanium alloys, which have higher melting points, to enable the production of plugs for the abandonment of deeper wells where subterranean temperatures are higher.

A through tubing bridge plug (200) for providing a gripping and sealing engagement with a casing string of a wellbore. The bridge plug (200) includes an actuation rod (208), an anchor assembly (212), a pair of compression assemblies, each including a support assembly (216, 242) and an anti extrusion assembly (220, 238) and a packing assembly (224) disposed about the actuation rod (208) between the compression assemblies. Responsive to longitudinal movement of the actuation rod (208), the anchor assembly (212) establishes the gripping engagement with the casing string, the compression assemblies are radially deployed such that the anti extrusion assemblies (220, 238) are supported by the support assemblies (216, 242) and the packing assembly (224) establishes the sealing engagement with the casing string.

A through tubing bridge plug (200) for providing a gripping and sealing engagement with a casing string of a wellbore. The bridge plug (200) includes an actuation rod (208), an anchor assembly (212), a pair of compression assemblies, each including a support assembly (216, 242) and an anti extrusion assembly (220, 238) and a packing assembly (224) disposed about the actuation rod (208) between the compression assemblies. Responsive to longitudinal movement of the actuation rod (208), the anchor assembly (212) establishes the gripping engagement with the casing string, the compression assemblies are radially deployed such that the anti extrusion assemblies (220, 238) are supported by the support assemblies (216, 242) and the packing assembly (224) establishes the sealing engagement with the casing string.

A downhole tool includes a support ring having an annular-shaped body, a thickness measured between an uphole side of the body and an opposite downhole side of the body, an extension distance measured between an inner diameter of the body and an outer diameter of the body, and one or more openings formed through the thickness of the body. A one-way valve is disposed in each opening formed through the support ring to limit flow through the support ring in a direction from the downhole side of the body to the uphole side of the body.

A downhole tool includes a support ring having an annular-shaped body, a thickness measured between an uphole side of the body and an opposite downhole side of the body, an extension distance measured between an inner diameter of the body and an outer diameter of the body, and one or more openings formed through the thickness of the body. A one-way valve is disposed in each opening formed through the support ring to limit flow through the support ring in a direction from the downhole side of the body to the uphole side of the body.