US3724062A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Explosively welded plug for leaky tubes of a heat exchanger and method of using the same
Assignee: Westinghouse Electric Corp
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Filing: 1971-03-18
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Granted: 1973-04-03
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Expires: 1991-03-18
Abstract
Abstract A plug for a leaky tube of a heat exchanger, the plug being weldable to the leaky tube by a shock wave propagated by an explosive charge disposed within the plug and a method of plugging a leaky tube by explosively welding the plug to the leaky tube.
Inventors
- 👤 R Cantrell
- 👤 L Sturiale
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 00:45
CPC Classifications
B; B23; B23K; B23K20/00; B23K20/06; B23K20/08; B23K20/085; F; F16; F16L; F16L41/00; F16L41/08; F16L41/082; F16L41/084; F28; F28F; F28F11/00; F28F11/02; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935; Y10T29/49352
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
181 words
A plug for an end of a tube, said plug being formed of a material capable of being welded to said tube by a shock wave propagated by an explosive charge, said plug comprising three integral portions, a forward portion having means for centering said forward end of said plug within said tube, a central portion of reduced cross section having an outer peripheral surface formed to provide generally equal spacing between said surface and said tube, and a rear portion having a gradually increasing cross section to provide means for centering said rear portion of said plug in said tube and for positioning the plug relative to said end of said tube, a central cavity formed by an axial opening of generally constant cross section and extending completely through said rear portion and said center portion and partially into said forward portion, an explosive charge disposed in a portion of said cavity adjacent said center portion of said plug, wadding disposed in said cavity to keep said explosive charge adjacent said center portion, and means for detonating said explosive charge.
Claim 2
Dependent Claim
181 words
A plug for an end of a tube, said plug being formed of a material capable of being welded to said tube by a shock wave propagated by an explosive charge, said plug comprising three integral portions, a forward portion having means for centering said forward end of said plug within said tube, a central portion of reduced cross section having an outer peripheral surface formed to provide generally equal spacing between said surface and said tube, and a rear portion having a gradually increasing cross section to provide means for centering said rear portion of said plug in said tube and for positioning the plug relative to said end of said tube, a central cavity formed by an axial opening of generally constant cross section and extending completely through said rear portion and said center portion and partially into said forward portion, an explosive charge disposed in a portion of said cavity adjacent said center portion of said plug, wadding disposed in said cavity to keep said explosive charge adjacent said center portion, and means for detonating said explosive charge.
Claim 3
Dependent Claim
24 words
A plug as set forth in claim 1, wherein the material of the plug is essentially the same as the material of the tube.
Claim 4
Dependent Claim
30 words
A plug as set forth in claim 1, wherein the forward portion of the plug is generally cylindrical and has a diameter slightly smaller than the diameter of the tube.
Claim 5
Dependent Claim
72 words
A plug as set forth in claim 3, wherein the forward portion of the plug has an axial opening extending inwardly from the forward end thereof and a plurality of kerfs disposed in the forward end of the plug and spaced girthwise therein, and the forward end of the plug is expanded outwardly to engage the tube for holding the plug in place prior to explosively welding the plug to the tube.
Claim 6
Dependent Claim
39 words
A plug as set forth in claim 1, wherein the rear portion thereof is frustoconical shape to provide the means for centering the rear portion of the plug and posi-tioning the plug relative to the end of the tube.
Claim 7
Dependent Claim
34 words
A plug as set forth in claim 1, wherein the central portion thereof has a thin wall of uniform thickness, said wall being substantially thinner than the walls of the forward and rear portions.
Claim 8
Independent Claim
216 words
A method of plugging one end of a tube utilizing a plug having three integral portions, a forward portion, which has means for centering said forward portion in said tube, a central portion of reduced cross section having an outer peripheral surface which is generally equally spaced from said tube when disposed therein and a rear portion which has a gradually increasing cross section to provide means for centering said plug in said tube and locating said plug relative to said end of said tube, and a central cavity having an axial opening of generally constant cross section extending through said rear and central portions and partially through said forward portion of said plug, said method comprising placing a forward wadding in said cavity so that said wadding plugs the cavity in the forward portion of the plug adjacent the central portion, placing a predetermined amount of explosive material in said cavity, placing a rear wadding with detonating meAns extending therethrough in said cavity to retain said explosive in the region of said central portion of said plug, inserting the forward end of said plug in said tube; pushing the plug as far into the tube as it will go, and detonating said explosive charge to explosively weld said plug to the end of said tube.
Claim 9
Independent Claim
216 words
A method of plugging one end of a tube utilizing a plug having three integral portions, a forward portion, which has means for centering said forward portion in said tube, a central portion of reduced cross section having an outer peripheral surface which is generally equally spaced from said tube when disposed therein and a rear portion which has a gradually increasing cross section to provide means for centering said plug in said tube and locating said plug relative to said end of said tube, and a central cavity having an axial opening of generally constant cross section extending through said rear and central portions and partially through said forward portion of said plug, said method comprising placing a forward wadding in said cavity so that said wadding plugs the cavity in the forward portion of the plug adjacent the central portion, placing a predetermined amount of explosive material in said cavity, placing a rear wadding with detonating meAns extending therethrough in said cavity to retain said explosive in the region of said central portion of said plug, inserting the forward end of said plug in said tube; pushing the plug as far into the tube as it will go, and detonating said explosive charge to explosively weld said plug to the end of said tube.
Claim 10
Dependent Claim
24 words
A method as set forth in claim 7 and further comprising cleaning the inside wall of the tube adjacent the end of the plug.
Claim 11
Dependent Claim
43 words
A method as set forth in claim 7 and further comprising inserting a temporary plug into the tube to provide a dam to prevent liquid from seeping into the area occupied by the plug prior to explosively welding the plug to the tube.
Claim 12
Dependent Claim
27 words
A method as set forth in claim 7 and further comprising cleaning the outer peripheral surface of the plug prior to inserting the plug in the tube.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |