US4829660A — System for removing a plug from a heat exchanger …

Claim 1

Independent Claim 153 words

A system for removing a plug from a conduit, wherein said pug is formed from an elongated shell having a closed end, an open end, and inner walls, said shell containing an expander element, and outer walls, and wherein said plug is expanded by axially pulling said expander element within said shell to radially expand said shell so that said outer walls sealingly engage the inner walls of said conduit to plug the same, comprising an expander removal means for pushing said expander element completely through said closed end of said shell while imparting a minimum amount of kinetic energy to said expander element and closed shell end to both relax said plug in said tube and to proved access in said shell, and fusing means for fusing at least one strip of the inner walls along the longitudinal axis of the shell in order to contract the outer walls of said shell.

Claim 2

Independent Claim 153 words

A system for removing a plug from a conduit, wherein said pug is formed from an elongated shell having a closed end, an open end, and inner walls, said shell containing an expander element, and outer walls, and wherein said plug is expanded by axially pulling said expander element within said shell to radially expand said shell so that said outer walls sealingly engage the inner walls of said conduit to plug the same, comprising an expander removal means for pushing said expander element completely through said closed end of said shell while imparting a minimum amount of kinetic energy to said expander element and closed shell end to both relax said plug in said tube and to proved access in said shell, and fusing means for fusing at least one strip of the inner walls along the longitudinal axis of the shell in order to contract the outer walls of said shell.

Claim 3

Independent Claim 44 words

The system of claims 1, wherein said expander removal means includes a pushing tip driven by a lead screw means to minimize the amount of kinetic energy imparted to the expander element when said element is pushed through said closed end of said shell.

Claim 4

Dependent Claim 26 words

The system of claim 1, wherein said expander removal means includes a floating coupling to facilitate alignment between said expander removal means and said expander element.

Claim 5

Dependent Claim 30 words

The system of claim 1, further including a pulling means for removing the plug shell from the conduit after the fusing means has contracted the outer walls of said shell.

Claim 6

Dependent Claim 24 words

The system of claim 4, wherein said pulling means includes a floating coupling to facilitate alignment between said pulling means and the plug shell.

Claim 7

Independent Claim 191 words

A system for removing a plug from a conduit, wherein said plug is of the type that includes an elongated shell having a closed end and an open end, and a shell interior that has a tapered wall section and an expander element that coacts therewith to expand the outer wall of the shell into engagement with the conduit when the expander element is moved from the closed end to the open end of the shell, comprising: a. a fusing means for fusing at least one strip of the inner walls of the shell along the longitudinal axis of the shell in order to contract the outer shell walls; b. an expander removal means for pushing the expander element from the open end of the shell through the closed end of the shell while imparting a minimum amount of kinetic energy to said expander element and closed shell end to both loosen the shell within the conduit and to provide access within the shell for the fusing means, and c. a pulling means for pulling the plug shell from the conduit after the fusing means has contracted the outer shell walls.

Claim 8

Independent Claim 191 words

A system for removing a plug from a conduit, wherein said plug is of the type that includes an elongated shell having a closed end and an open end, and a shell interior that has a tapered wall section and an expander element that coacts therewith to expand the outer wall of the shell into engagement with the conduit when the expander element is moved from the closed end to the open end of the shell, comprising: a. a fusing means for fusing at least one strip of the inner walls of the shell along the longitudinal axis of the shell in order to contract the outer shell walls; b. an expander removal means for pushing the expander element from the open end of the shell through the closed end of the shell while imparting a minimum amount of kinetic energy to said expander element and closed shell end to both loosen the shell within the conduit and to provide access within the shell for the fusing means, and c. a pulling means for pulling the plug shell from the conduit after the fusing means has contracted the outer shell walls.

Claim 9

Dependent Claim 26 words

The system of claim 6, wherein said expander removal means includes a floating coupling to facilitate alignment between said expander removal means and said expander element.

Claim 10

Dependent Claim 38 words

The system of claim 7, wherein the expander removal means includes a pushing tip for engaging and pushing the expander element, and wherein said floating coupling connects said pushing tip to the rest of the expander removal means.

Claim 11

Dependent Claim 24 words

The system of claim 6, wherein said pulling means includes a floating coupling to facilitate alignment between said pulling means and the plug shell.

Claim 12

Dependent Claim 39 words

The system of claim 9, wherein the pulling means includes a pulling tip for engaging and pulling the plug shell from the conduit, and wherein the floating coupling connects the pulling tip to the rest of the pulling means.

Claim 13

Dependent Claim 33 words

The system of claim 6, wherein the fusing means includes a welding torch that creates at least one welding bead on the inner walls of the plug shell along the longitudinal axis thereof.

Claim 14

Dependent Claim 65 words

The system of claim 6, wherein the expander removal means includes a pushing mechanism having a pushing tip for engaging and pushing the expander element, and a leadscrew drive assembly for driving the pushing tip against the expander element and for minimizing the amount of kinetic energy imparted to the expander element when said element is pushed through the closed end of the plug shell.

Claim 15

Dependent Claim 49 words

The system of claim 6, further including a frame for supporting said expander removal means and said pulling means, wherein said frame includes means for remotely monitoring the relative positions of a plug shell to be removed from a conduit, and said expander removal means and said pulling means.

Claim 16

Independent Claim 216 words

A system for removing a metallic plug from a tube, wherein said plug is of the type that includes an elongated shell having a closed end and an open end, and a shell interior that has a tapered inner wall section and an expander element that coacts therewith to expand the outer wall of the shell into sealing engagement with the inner wall of the tube when the expander element is moved from the closed end to the open end of the shell, comprising: a. a welding means for creating at least one weld bead along the longitudinal axis of the tapered inner wall of the shell in order to contract the outer shell wall; b. a remotely operable expander removal means having a distal end for pushing the expander element from the open end completely through the closed end of the shell in order to relax the engagement between the outer wall of the shell against the inner wall of the tube and to provide access to the tapered inner wall of the shell for the welding means, and c. A remotely operable pulling means having a distal end for pulling the plug shell from the tube after the welding means has created said wall-contracting weld bead on the tapered inner wall of the shell.

Claim 17

Independent Claim 216 words

A system for removing a metallic plug from a tube, wherein said plug is of the type that includes an elongated shell having a closed end and an open end, and a shell interior that has a tapered inner wall section and an expander element that coacts therewith to expand the outer wall of the shell into sealing engagement with the inner wall of the tube when the expander element is moved from the closed end to the open end of the shell, comprising: a. a welding means for creating at least one weld bead along the longitudinal axis of the tapered inner wall of the shell in order to contract the outer shell wall; b. a remotely operable expander removal means having a distal end for pushing the expander element from the open end completely through the closed end of the shell in order to relax the engagement between the outer wall of the shell against the inner wall of the tube and to provide access to the tapered inner wall of the shell for the welding means, and c. A remotely operable pulling means having a distal end for pulling the plug shell from the tube after the welding means has created said wall-contracting weld bead on the tapered inner wall of the shell.

Claim 18

Dependent Claim 66 words

The system of claim 14, wherein both said expander removal means and said pulling means include a floating coupling for allowing the distal ends of each to move orthogonally with respect to the longitudinal axis of the shell when said distal ends are remotely moved into engagement with said plug shell, thereby facilitating alignment between said expander removal means, said pulling means, and said plug shell.

Claim 19

Dependent Claim 49 words

The system of claim 14, further including a frame for supporting said expander removal means and said pulling means, wherein said frame includes means for remotely monitoring the relative positions of a plug shell to be removed from a conduit, and said expander removal means and said pulling means.

Claim 20

Dependent Claim 86 words

The system of claim 14, wherein the plug shell is screw-threaded around its open end, and the expander removal means includes a pushing mechanism having a pushing tip for engaging and pushing the expander element, and a threaded fitting that surrounds the pushing tip for connecting the pushing mechanism to the threaded open end of the plug shell, and wherein the threaded fitting includes screw threads that are undercut relative to the screw threads of the plug shell in order to facilitate the threaded engagement therebetween.

Claim 21

Independent Claim 337 words

A system for removing a metallic plug from a heat exchanger tube, wherein the plug is of the type that includes an elongated shell having a closed end and an open end, and a shell interior that has a tapered inner wall section and an expander element that coacts therewith to expand the outer wall of the plug shell into sealing engagement with the inner wall of the tube when the expander element is moved from the closed end to the open end of the shell, comprising: a. a welding means including a tungsten-inert gas torch for creating a plurality of weld beads on the inner tapered wall section of the plug along the longitudinal axis thereof in order to contract the outer shell wall; b. a remotely operable expander removal means having a pushing tip for pushing the expander element from the open end completely through the closed end of the shell in order to provide access to the tapered inner wall section of the shell for the torch and further to relax the engagement between the outer walls of the shell and the tube, wherein said expander removal means includes a pushing tip that is driven by a leadscrew means to minimize the amount of kinetic energy imparted to the expander element and closed end of said shell when said element is pushed through said closed end of said shell and a floating coupling for allowing the pushing tip to move orthogonally with respect to the longitudinal axis of the shell thereby facilitating alignment between the pushing tip and the plug shell, and c. a remotely operable pulling means having a pulling tip for pulling the plug shell from the tube after the torch applies said plurality of weld beads on said inner tapered wall section of said shell, and a floating coupling for allowing the pulling tip to move orthogonally with respect to the longitudinal axis of the shell thereby facilitating alignment between the pulling tip of the pulling means and the plug shell.

Claim 22

Independent Claim 337 words

A system for removing a metallic plug from a heat exchanger tube, wherein the plug is of the type that includes an elongated shell having a closed end and an open end, and a shell interior that has a tapered inner wall section and an expander element that coacts therewith to expand the outer wall of the plug shell into sealing engagement with the inner wall of the tube when the expander element is moved from the closed end to the open end of the shell, comprising: a. a welding means including a tungsten-inert gas torch for creating a plurality of weld beads on the inner tapered wall section of the plug along the longitudinal axis thereof in order to contract the outer shell wall; b. a remotely operable expander removal means having a pushing tip for pushing the expander element from the open end completely through the closed end of the shell in order to provide access to the tapered inner wall section of the shell for the torch and further to relax the engagement between the outer walls of the shell and the tube, wherein said expander removal means includes a pushing tip that is driven by a leadscrew means to minimize the amount of kinetic energy imparted to the expander element and closed end of said shell when said element is pushed through said closed end of said shell and a floating coupling for allowing the pushing tip to move orthogonally with respect to the longitudinal axis of the shell thereby facilitating alignment between the pushing tip and the plug shell, and c. a remotely operable pulling means having a pulling tip for pulling the plug shell from the tube after the torch applies said plurality of weld beads on said inner tapered wall section of said shell, and a floating coupling for allowing the pulling tip to move orthogonally with respect to the longitudinal axis of the shell thereby facilitating alignment between the pulling tip of the pulling means and the plug shell.

Claim 23

Dependent Claim 31 words

The system of claim 18, wherein the pushing tip includes retaining means for retaining the expander element after said element is pushed completely through the closed end of the plug shell.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1992-05-15	1992-11-14	1993-05-16	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1996-05-15	1996-11-14	1997-05-16	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2000-05-15	2000-11-14	2001-05-16	$7700.00	Window Closed / Lapsed

System for removing a plug from a heat exchanger tube

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