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US4125937A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for hydraulically expanding a tube

Assignee: Westinghouse Electric Corp
•
Filing: 1977-06-28
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Granted: 1978-11-21
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Expires: 1997-06-28
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Abstract

Abstract A mandrel that forms an annular space when inserted within a tube and has O rings adjacent each end and a leading end having a tapered portion and a spring cooperatively associated with the O ring to facilitate sliding the mandrel into the tube and forming a fluid-tight seal adjacent the leading end of the mandrel so that pressurized fluid can be introduced into the annular space to expand the tube into engagement with a tube sheet.

Inventors

  • 👤 Philip S. Brown
  • 👤 Douglas G. Harman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 09:39
CPC Classifications
B; B21; B21D; B21D39/00; B21D39/06; B21D39/08; B21D39/20; B21D39/203; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935; Y10T29/49373; Y10T29/49375; Y10T29/49805; Y10T29/53; Y10T29/53113; Y10T29/53122

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 209 words
Apparatus for hydraulically expanding a tube into engagement with a tube sheet, said apparatus comprising: a mandrel having an outer diameter smaller than the inner diameter of said tube so as to form an annular cavity between the tube and the mandrel when the mandrel is inserted in said tube; said mandrel having a fluid inlet port in one end thereof; said fluid inlet port being in fluid communication with said annular cavity; said one end having a shoulder extending radially outwardly beyond the inner diameter of said tube; a circumferential groove adjacent said one end of said tube for receiving a first sealing means which forms a fluid type seal adjacent said one end of said cavity; a tapered portion adjacent said other end of said mandrel; said tapered portion expanding outwardly as it approaches said other end of said mandrel; a second sealing means disposed on said tapered portion and forming a seal adjacent the other end of said cavity; and means for biasing said second sealing means toward the other end of said mandrel, whereby said mandrel may be easily slipped into said tube without damaging the sealing means which first enters the tube and providing a fluid-tight seal adjacent each end of the annular space.
Claim 2
Dependent Claim 209 words
Apparatus for hydraulically expanding a tube into engagement with a tube sheet, said apparatus comprising: a mandrel having an outer diameter smaller than the inner diameter of said tube so as to form an annular cavity between the tube and the mandrel when the mandrel is inserted in said tube; said mandrel having a fluid inlet port in one end thereof; said fluid inlet port being in fluid communication with said annular cavity; said one end having a shoulder extending radially outwardly beyond the inner diameter of said tube; a circumferential groove adjacent said one end of said tube for receiving a first sealing means which forms a fluid type seal adjacent said one end of said cavity; a tapered portion adjacent said other end of said mandrel; said tapered portion expanding outwardly as it approaches said other end of said mandrel; a second sealing means disposed on said tapered portion and forming a seal adjacent the other end of said cavity; and means for biasing said second sealing means toward the other end of said mandrel, whereby said mandrel may be easily slipped into said tube without damaging the sealing means which first enters the tube and providing a fluid-tight seal adjacent each end of the annular space.
Claim 3
Dependent Claim 14 words
Apparatus as set forth in claim 1, wherein the sealing means are O rings.
Claim 4
Dependent Claim 29 words
Apparatus as set forth in claim 1, wherein the second sealing means is an O ring having an outer diameter slightly smaller than the inner diameter of the tube.
Claim 5
Dependent Claim 26 words
Apparatus as set forth in claim 1, and further comprising an elastomer washer disposed on the tapered portion of the mandrel adjacent the other end thereof.
Claim 6
Dependent Claim 19 words
Apparatus as set forth in claim 1, wherein the means for biasing the second sealing means is a spring.

References Cited (Backward Citations)

US2460580A Cited
US2479702A Cited
US3979810A Cited
US3977068A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-11-20 1982-05-22 1982-11-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-11-20 1986-05-22 1986-11-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-11-20 1990-05-22 1990-11-21 $7700.00 Window Closed / Lapsed

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