US3216095A - Method of securing fins to tubes - Google Patents

Method of securing fins to tubes Download PDF

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Publication number
US3216095A
US3216095A US173787A US17378762A US3216095A US 3216095 A US3216095 A US 3216095A US 173787 A US173787 A US 173787A US 17378762 A US17378762 A US 17378762A US 3216095 A US3216095 A US 3216095A
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United States
Prior art keywords
fin
slot
tubular member
opening
fins
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US173787A
Inventor
Orville C Kurtz
Harold C Thompson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alstom Power Inc
Original Assignee
Air Preheater Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by Air Preheater Co Inc filed Critical Air Preheater Co Inc
Priority to US173787A priority Critical patent/US3216095A/en
Application granted granted Critical
Publication of US3216095A publication Critical patent/US3216095A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
    • B21C37/15—Making tubes of special shape; Making tube fittings
    • B21C37/22—Making finned or ribbed tubes by fixing strip or like material to tubes
    • B21C37/24—Making finned or ribbed tubes by fixing strip or like material to tubes annularly-ribbed tubes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
    • F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
    • F28F1/24—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely
    • F28F1/30—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely the means being attachable to the element
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2215/00—Fins
    • F28F2215/12—Fins with U-shaped slots for laterally inserting conduits
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/4935—Heat exchanger or boiler making
    • Y10T29/49377—Tube with heat transfer means
    • Y10T29/49378—Finned tube
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/4935—Heat exchanger or boiler making
    • Y10T29/49393—Heat exchanger or boiler making with metallurgical bonding
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49826—Assembling or joining
    • Y10T29/49863—Assembling or joining with prestressing of part
    • Y10T29/49865—Assembling or joining with prestressing of part by temperature differential [e.g., shrink fit]

Definitions

  • This invention relates to heat exchange apparatus and particularly to a tube type heat exchanger and a method of tightly securing a series of extended surface fins thereto.
  • I Fins or extended surface means have long been variously secured. to tube type heat exchange elements to facilitate the transfer of heat between a fluid flowing through a passageway within the tube and a fluid flowing over the fins outside the tube.
  • Such fins perform their intended function most efliciently when they tightly embrace the tubes through which the fluid is being directed, and to secure the desired fitting, thin fins are usually crimped or soldered to a central tube, or a flexible central tube is expanded into a tight fit with its surrounding fins in order that the best possible connection be obtained.
  • heat exchange fins for such applications be formed of /g steel plate while the fluid carrying pipe is comprised of a heavy 4" steel pipe.
  • the fins are commonly welded individually to the pipe to provide a good bond therebetween that readily transmits heat between the spaced fluids. It is apparent that the fabricator of such heavy stock into an effective heat exchanger may present many problems not associated with the fabrication of the usual light gauge material.
  • this invention has as its chief object to provide a method of producing a heavy duty fin tube arrangement that is both eflicient and rug'gedly strong.
  • reference numeral 12 desigplication of a force F to opposite sides of the fin in a direction generally normal to the slot 18 will tend to close the slot and reduce the diameter of the aperture 16.
  • the annular surface of the aperture embraces the outer surface of the tubular member to hold the fin in any predetermined position with respect to the tubular member 12.
  • the slot is welded shut with a metallic weld 22 that locks the aperture of the fin tightly about the tubular member.
  • a metallic weld 22 that locks the aperture of the fin tightly about the tubular member.
  • Fin members thus connected to a central tubular member are mechanically independent. However, they are frictionally held so tightly that the transfer of heat between a fluid flowing through the tubular member and a fluid flow-ing across the fins attains a consistently high the steps of forming an opening in said fin slightly larger nates ametallic tubular member provided with a series of longitudinally spaced extended surface fins 14 over which one fluid is adapted to flow in heat exchange relation with a second fluid which is directed through the Each fin 14 comprises essentially a plane metallic sheet having a central aperture 16 formed :with a diameter slightly greater than the diameter of the tubular'member 12 around which it is adapted to extend.
  • Each extended surface fin 14 is provided with a single radial slot 18 that extends from its central aperture to its outer periphcry.
  • the width w'-of each-slo.t,thus formed is of greater extent than the difference between the circumference of the aperture 16 inthe fin 14 andthe: outside circumference of the tubular member 12
  • the apthan the outer dimensions of said tubular member, forming a radial slot in said fin extending from said opening to its outer periphery, inserting said tubular member into the opening in said extended surface, exerting a force on said fin tending to close the slot and simultaneously filling each slot with a molten metallic material that bonds itself to the spaced edges of said slot and upon.
  • cooling solidifies and contracts to draw the edges of said slot into a mutually closer relationship whereby the opening in said tin tightly embraces the outer surface of the tubular member.

Description

Nov. 9, 1965 c, KURTZ ETAL 3,216,095
METHOD OF SECURING FINS TO TUBES Filed Feb.' 15, 1962 passageway within the tubular member.
United States Patent 3,216,095 METHOD OF SECURING FINS T0 TUBES Orville C. Kurtz and Harold G. Thompson, Wellsville, N.Y., assignors, by mesne assignments, to The Air Preheater Company, Inc., a corporation of Delaware Filed Feb. 16, 1962, Ser. No. 173,787 2 Claims. '(Cl. 29--157.3)
This invention relates to heat exchange apparatus and particularly to a tube type heat exchanger and a method of tightly securing a series of extended surface fins thereto.
I Fins or extended surface means have long been variously secured. to tube type heat exchange elements to facilitate the transfer of heat between a fluid flowing through a passageway within the tube and a fluid flowing over the fins outside the tube. Such fins perform their intended function most efliciently when they tightly embrace the tubes through which the fluid is being directed, and to secure the desired fitting, thin fins are usually crimped or soldered to a central tube, or a flexible central tube is expanded into a tight fit with its surrounding fins in order that the best possible connection be obtained.
For heat exchange equipment adapted for use in the handling of large volumes of fluid in a corrosive atmos-- phere, especially where long equipment life and a high rate'of heat transfer is required, the usual heat exchange fins formed of thin metallic sheet are not adequate and the use of large capacity pipe with comparably heavy fins becomes mandatory.
Thus it is not unusual for heat exchange fins for such applications be formed of /g steel plate while the fluid carrying pipe is comprised of a heavy 4" steel pipe.
The fins are commonly welded individually to the pipe to provide a good bond therebetween that readily transmits heat between the spaced fluids. It is apparent that the fabricator of such heavy stock into an effective heat exchanger may present many problems not associated with the fabrication of the usual light gauge material. Thus this invention has as its chief object to provide a method of producing a heavy duty fin tube arrangement that is both eflicient and rug'gedly strong.
Still further and more detailed objects of the invention will become more apparent when viewed in conjunction with the accompanying drawing in which the single figure is a perspective view of a fin tube heat exchange element, assembled according to the present invention.
Referring to the drawing, reference numeral 12 desigplication of a force F to opposite sides of the fin in a direction generally normal to the slot 18 will tend to close the slot and reduce the diameter of the aperture 16. As the diameter of the aperture is reduced, the annular surface of the aperture embraces the outer surface of the tubular member to hold the fin in any predetermined position with respect to the tubular member 12.
The manner in which or the means by which the required transverse force is applied to each fin to close its radial slot is of no particular significance as long as the force is applied generally normal to the slot. Thus apparatus devised to clamp a single or multiple fin assembly may be used selectively without altering the basic concept of the invention.
During the period in which the slot 18 is compressed and the surface of aperture 16 is held in close contact with the outer surface of the tubular member 12, the slot is welded shut with a metallic weld 22 that locks the aperture of the fin tightly about the tubular member. As I the weld in the slot cools, it solidifies, grips the sides of the slot and contracts to decrease the diameter of the aperture and cause the inner surface of the aperture to grip more firmly the outer surface of tube 12 whereby the fin is in effect locked even more firmly in its predetermined position on the tube.
Fin members thus connected to a central tubular member are mechanically independent. However, they are frictionally held so tightly that the transfer of heat between a fluid flowing through the tubular member and a fluid flow-ing across the fins attains a consistently high the steps of forming an opening in said fin slightly larger nates ametallic tubular member provided with a series of longitudinally spaced extended surface fins 14 over which one fluid is adapted to flow in heat exchange relation with a second fluid which is directed through the Each fin 14 comprises essentially a plane metallic sheet having a central aperture 16 formed :with a diameter slightly greater than the diameter of the tubular'member 12 around which it is adapted to extend. Each extended surface fin 14 is provided with a single radial slot 18 that extends from its central aperture to its outer periphcry. The width w'-of each-slo.t,thus formed is of greater extent than the difference between the circumference of the aperture 16 inthe fin 14 andthe: outside circumference of the tubular member 12 Thus the apthan the outer dimensions of said tubular member, forming a radial slot in said fin extending from said opening to its outer periphery, inserting said tubular member into the opening in said extended surface, exerting a force on said fin tending to close the slot and simultaneously filling each slot with a molten metallic material that bonds itself to the spaced edges of said slot and upon.
cooling solidifies and contracts to draw the edges of said slot into a mutually closer relationship whereby the opening in said tin tightly embraces the outer surface of the tubular member.
2. The method of firmly securing a transverse extended surface fin to the outer surface of a tubular member comprising the steps of forming an opening in said fin with a diameter greater than the outside diameter of said tubular member, forming a radial slot in said fin with a transverse width greater than the difference between the circumference of the opening in said fin and that of the outer surface of said tubular member, fitting said fin around said tubular member according to a predetermined arrangement, exterting a force on said fin in a direction transverse the longitudinal axis of the slot to decrease the diameter of said opening until the fin tightly embraces the tubular member, and filling 3,216,095 Patented Nov. .9, 19
3 4 said slot with a metallic weld that interconnects the 2,356,779 8/44 Morrison.
spaced edges of said slot and upon cooling contracts to 2,453,567 11/48 Bronandcr 165--182 X draw said fin into closer contact with {he tub'ul ar member. 2,468,503 4/49 Lister 29-447 X 4 i 2,574,142 11/51 Buongirno 29-1573 X References Cited by the Examiner 5 3,158,352 7 11/ 64 Grove.
UNITED STATESPATENTS FOREIGN A S 4 0, 1 11/90 Weisel- 1 725,382 3/55 Great Britain. 1,775,706 I 9/30 Trane. 2,219,085 10/40 Watson. 10 WHITMORE A. WILTZ, Primary Examiner.

Claims (1)

1. THE METHOD OF SECURING AN EXTENDED SURFACE FIN TO THE OUTER SURFACE OF A TUBULAR MEMBER THAT COMPRISES THE STEPS OF FORMING AN OPENING IN SAID FIN SLIGHTLY LARGER THAN THE OUTER DIMENSIONS OF SAID TUBULAR MEMBER, FORMING A RADIAL SLOT IN SAID FIN EXZTENDING FROM SAID OPENING TO OUTER PERIPHERY, INSERTING SAID TUBULAR MEMBER INTO THE OPENING IN SAID EXTENDED SURFACE, EXERTING A FORCE ON SAID FIN TENDING TO CLOSE THE SLOT AND SIMULTANEOUSLY FILLING EACH SLOT WITH A MOLTEN METALLIC MATERIAL THAT BONDS ITSELF TO THE SPACE EDGES OF SAID SLOT AND UPON COOLING SOLIDIFIES AND CONTRACTS TO DRAW THE EDGES OF SAID SLOT INTO A MUTUALLY CLOSER RELATIONSHIP WHEREBY THE OPENING IN SAID TIN TIGHTLY EMBRACES THE OUTER SURFACE OF THE TUBULAR MEMBER.
US173787A 1962-02-16 1962-02-16 Method of securing fins to tubes Expired - Lifetime US3216095A (en)

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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3284882A (en) * 1963-05-13 1966-11-15 Comunita Dei Cisterciensi Rifo Process of embodying chaplets with beads made of coconut husk material or the like fixed on a continuous chain
US3433300A (en) * 1966-09-01 1969-03-18 Peerless Of America Heat exchangers and the method of making same
US3877128A (en) * 1969-01-21 1975-04-15 Airco Inc Method of producing a finned tube heat exchanger
US3999277A (en) * 1974-07-02 1976-12-28 Hiroshi Hamada Method of manufacturing assembly-type camshaft
US4856165A (en) * 1987-10-01 1989-08-15 Man Technologie Gmbh Method for producing by welding a finned heat exchanger pipe
US6266882B1 (en) * 1999-05-20 2001-07-31 Carrier Corporation Fin collar and method of manufacturing
US6435266B1 (en) * 2001-05-01 2002-08-20 Aavid Taiwan Inc. Heat-pipe type radiator and method for producing the same
US6550529B1 (en) * 2002-04-17 2003-04-22 Sunonwealth Electric Machine Industry Co., Ltd. Heatsink device
US20040111886A1 (en) * 2002-02-21 2004-06-17 Wenger Todd Michael Fin with elongated hole and heat pipe with elongated cross section
US20050039890A1 (en) * 2003-08-08 2005-02-24 Lee Hsieh Kun Heat dissipating device and method of making it
US20060201657A1 (en) * 2004-11-24 2006-09-14 Jia-Hao Li Heat-Dissipating Fin Set in Combination with Thermal Pipe
US20060232941A1 (en) * 2005-04-18 2006-10-19 Cooler Master Co., Ltd. Heat sink and the method for making the same
US9605909B2 (en) 2012-07-18 2017-03-28 Fab Tek Logic, Llc Removable radiator fin assembly
US10281221B2 (en) 2012-07-18 2019-05-07 Fab Tek Logic, Llc Removable heatsink fin assembly
US11774187B2 (en) * 2018-04-19 2023-10-03 Kyungdong Navien Co., Ltd. Heat transfer fin of fin-tube type heat exchanger

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US440671A (en) * 1890-11-18 Disk for refrigerating and heating pipes
US1775706A (en) * 1926-06-19 1930-09-16 Reuben N Trane Radiator
US2219085A (en) * 1938-09-01 1940-10-22 Charles G Watson Method of covering rollers
US2356779A (en) * 1940-10-31 1944-08-29 Willard L Morrison Apparatus for freezing foods
US2453567A (en) * 1944-09-23 1948-11-09 Wilhelm B Bronander Cooling fin structure for internalcombustion engines
US2468503A (en) * 1946-10-12 1949-04-26 Huber Corp J M Method of making tubing cleaners
US2574142A (en) * 1950-07-12 1951-11-06 Frank G Buongirno Radiator fin for pipes
GB725382A (en) * 1952-05-27 1955-03-02 Athano Nv An improved method of and means for the manufacture of ribbed tubes
US3158352A (en) * 1961-08-16 1964-11-24 Marvin H Grove Clamped gate valve body

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US440671A (en) * 1890-11-18 Disk for refrigerating and heating pipes
US1775706A (en) * 1926-06-19 1930-09-16 Reuben N Trane Radiator
US2219085A (en) * 1938-09-01 1940-10-22 Charles G Watson Method of covering rollers
US2356779A (en) * 1940-10-31 1944-08-29 Willard L Morrison Apparatus for freezing foods
US2453567A (en) * 1944-09-23 1948-11-09 Wilhelm B Bronander Cooling fin structure for internalcombustion engines
US2468503A (en) * 1946-10-12 1949-04-26 Huber Corp J M Method of making tubing cleaners
US2574142A (en) * 1950-07-12 1951-11-06 Frank G Buongirno Radiator fin for pipes
GB725382A (en) * 1952-05-27 1955-03-02 Athano Nv An improved method of and means for the manufacture of ribbed tubes
US3158352A (en) * 1961-08-16 1964-11-24 Marvin H Grove Clamped gate valve body

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3284882A (en) * 1963-05-13 1966-11-15 Comunita Dei Cisterciensi Rifo Process of embodying chaplets with beads made of coconut husk material or the like fixed on a continuous chain
US3433300A (en) * 1966-09-01 1969-03-18 Peerless Of America Heat exchangers and the method of making same
US3877128A (en) * 1969-01-21 1975-04-15 Airco Inc Method of producing a finned tube heat exchanger
US3999277A (en) * 1974-07-02 1976-12-28 Hiroshi Hamada Method of manufacturing assembly-type camshaft
US4856165A (en) * 1987-10-01 1989-08-15 Man Technologie Gmbh Method for producing by welding a finned heat exchanger pipe
EP1054226B1 (en) 1999-05-20 2017-10-25 Carrier Corporation Improved fin collar and method of manufacturing
US6266882B1 (en) * 1999-05-20 2001-07-31 Carrier Corporation Fin collar and method of manufacturing
US6513587B2 (en) 1999-05-20 2003-02-04 Carrier Corporation Fin collar and method of manufacturing
US6435266B1 (en) * 2001-05-01 2002-08-20 Aavid Taiwan Inc. Heat-pipe type radiator and method for producing the same
US20040111886A1 (en) * 2002-02-21 2004-06-17 Wenger Todd Michael Fin with elongated hole and heat pipe with elongated cross section
US6550529B1 (en) * 2002-04-17 2003-04-22 Sunonwealth Electric Machine Industry Co., Ltd. Heatsink device
US20050039890A1 (en) * 2003-08-08 2005-02-24 Lee Hsieh Kun Heat dissipating device and method of making it
US20060201657A1 (en) * 2004-11-24 2006-09-14 Jia-Hao Li Heat-Dissipating Fin Set in Combination with Thermal Pipe
US20060232941A1 (en) * 2005-04-18 2006-10-19 Cooler Master Co., Ltd. Heat sink and the method for making the same
US9605909B2 (en) 2012-07-18 2017-03-28 Fab Tek Logic, Llc Removable radiator fin assembly
US10281221B2 (en) 2012-07-18 2019-05-07 Fab Tek Logic, Llc Removable heatsink fin assembly
US11774187B2 (en) * 2018-04-19 2023-10-03 Kyungdong Navien Co., Ltd. Heat transfer fin of fin-tube type heat exchanger

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