Plugging apparatus and method using a hydraulically assisted plug expander

A plugging apparatus for plugging a conduit comprising:

• (a) a plug shell having a closed end and an open end, and an interior defined by tapered walls;
• (b) an expander element contained within the plug shell interior and sealingly engaged around said tapered walls, said element being movable across the plug shell between the closed and open ends of the shell when a force is applied to said element for wedgingly spreading said tapered interior walls and radially expanding the shell, and
• (c) an expansion means including a mandrel connected to a source of pressurized hydraulic fluid for facilitating the movement of the expander element across the plug shell by conducting said fluid to the shell interior, thereby spreading said tapered walls and reducing the amount of force necessary to move said element, wherein said mandrel is detachably connectable to said expander element, and wherein said mandrel includes a piston face in fluid communication with said pressurized hydraulic fluid for generating and applying a pulling force onto said expander element.

A plugging apparatus for plugging a conduit, comprising:

• (a) a plug shell having a closed end and an open end, and an interior defined by tapered walls;
• (b) an expander element contained within the plug shell interior and sealingly engageable to said tapered walls, said element being movable between the closed end and open ends of the shell when a force is applied thereto for wedgingly engaging said tapered interior walls and radially expanding the shell, and
• (c) an expansion means including a mandrel connected to a source of pressurized hydraulic fluid for conducting said fluid into the plug shell and thereby facilitating the movement of the expander element across the plug shell by spreading said tapered walls and reducing the amount of force necessary to move said element, wherein said mandrel is detachably connected to the expansion element, and includes a piston means in communication with said pressurized fluid for generating and applying a pulling force onto said expander element.

A plugging apparatus for plugging a conduit, comprising:

• (a) a plug shell having a closed end and an open end;
• (b) an expander element contained within the interior of the shell and sealingly engaged therein that is movable across said shell between the closed end and open end thereof and that wedgingly engages the shell and radially expands it when so moved, and
• (c) an expansion means including both a source of pressurized hydraulic fluid for facilitating said movement of the expander element by conducting said fluid to the shell interior, thereby expanding the shell interior away from the expander element and relaxing the engagement therebetween, and a rod means detachably connectable to the expander element for applying sufficient pulling force to said element to move it across said shell.