US3559437A - Method and apparatus for making heat transfer tubing - Google Patents
Method and apparatus for making heat transfer tubing Download PDFInfo
- Publication number
- US3559437A US3559437A US773065A US3559437DA US3559437A US 3559437 A US3559437 A US 3559437A US 773065 A US773065 A US 773065A US 3559437D A US3559437D A US 3559437DA US 3559437 A US3559437 A US 3559437A
- Authority
- US
- United States
- Prior art keywords
- external
- fins
- tube
- internal
- helical
- 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
Links
Images
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
- B21C37/20—Making helical or similar guides in or on tubes without removing material, e.g. by drawing same over mandrels, by pushing same through dies ; Making tubes with angled walls, ribbed tubes and tubes with decorated walls
- B21C37/207—Making helical or similar guides in or on tubes without removing material, e.g. by drawing same over mandrels, by pushing same through dies ; Making tubes with angled walls, ribbed tubes and tubes with decorated walls with helical guides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D15/00—Corrugating tubes
- B21D15/04—Corrugating tubes transversely, e.g. helically
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28B—STEAM OR VAPOUR CONDENSERS
- F28B1/00—Condensers in which the steam or vapour is separate from the cooling medium by walls, e.g. surface condenser
- F28B1/02—Condensers in which the steam or vapour is separate from the cooling medium by walls, e.g. surface condenser using water or other liquid as the cooling medium
-
- 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
- F28F1/34—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 obliquely
- F28F1/36—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 obliquely the means being helically wound fins or wire spirals
-
- 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
- F28F1/42—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being both outside and inside the tubular 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
- 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
- F28F1/42—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being both outside and inside the tubular element
- F28F1/422—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being both outside and inside the tubular element with outside means integral with the tubular element and inside means integral with the tubular 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
- F28F13/00—Arrangements for modifying heat-transfer, e.g. increasing, decreasing
- F28F13/06—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by affecting the pattern of flow of the heat-exchange media
-
- 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
- Y10T29/49382—Helically finned
Definitions
- the present invention relates to method and apparatus for producing heat transfer tubing which represents an improvement over Rodgers Pat. 3,217,799 in which a heat transfer tube was provided having internal ridge portions or ribs, the ratio between the axial spacing of adjacent ridge portions to the radial height thereof being between 5:1 and 15:1.
- This patent shows the formation of the internal ribs opposite external grooves, the external grooves in particular resulting from the operation which produced the internal ridges or ribs.
- a helically ribbed roll is provided for deepening one of the external helical grooves, the roll being positioned with its axis parallel to the axis of the advancing tube.
- the roll may also be positioned so that its axis forms an "angle with the axis of the tube; in which case the pitch of the helical ribs on the roll would be chosen to give the desired tracking of the roll helix in the groove to be deepened.
- FIGS. 1, 2 and 3 are longitudinal sectional views through tubing formed in accordance with the present invention.
- FIG. 4 is a fragmentary sectional View illustrating one form of method and apparatus for producing tubing as shown in FIGS. l-3.
- FIG. 5 is a view similar to FIG. 4 illustrating another method and apparatus for forming the tubing.
- the present invention relates particularly to improved configurations of tubing for the transfer of heat as required for condensation of vapor on the external surface of tfluid cooled tubes.
- An example of such heat transfer application is that of steam condensing on watercooled tubes.
- Further examples might involve: vapor heating of viscous process fluids; or, in the case of cascade refrigeration, refrigerant vapor condensing on the external surface of tubing, with a second refrigerant being boiled as it flows through the tubing.
- the prior Rodgers patent emphasized the importance of the ratio S/H in which S is the axial spacing between adjacent convolutions of the internal rib, and H is the radial height of the internal rib, on the internal heat transfer performance.
- the disclosure is of an arrangement in which the number and axial spacing between external fins and internal fins is identical. This results from the fact that the internal ribs are produced by a rolling operation displacing material from external grooves into the external fin configuration.
- tubes are formed which have an external fin configuration consisting of a plurality of helically disposed continuous fins, the fins being arranged in the manner of a multiple-start screw so that in the case of a two-start fin for example, adjacent convolutions of fins throughout the length of the tube are portions of diflerent fins.
- an external fin configuration comprising a multiplicity of interleaved separate external continuous helical fins
- one of this multiplicity of grooves is deepened by an operation in which the material of the tube is displaced inwardly to produce a single continuous internal helical rib which accordingly extends opposite to and matches the external helical groove which was deepened to form the internal rib.
- the single internal rib will have a pitch or axial spacing between adjacent convolutions equal to twice the pitch or axial spacing between adjacent convolutions of the external fin.
- the axial spacing or pitch between adjacent convolutions of the internal rib will be 11 times as great as the pitch or axial spacing between adjacent convolutions of the external fins.
- FIG. 1 there is shown a fragmentary section of a tube having two starts producing two continuous helical fins one of which is designated at 12 and the other at 14. This results in the corresponding formation of two separate helical grooves 16 and .18.
- the groove 16 is allowed to remain in the condition existing after material has been displaced therefrom by rolling to form the adjacent fins l2 and 14.
- the remaining helical groove 18 is illustrated as having been deepened so as to produce an internal helically extending rib 19. It will be apparent by inspection that the axial spacing Si between adjacent convolutions of the internal rib is substantially double the pitch or axial spacing Se between adjacent fin convolutions at the exterior of the tube.
- the ribs and fins may if desired, be provided to extend straight around the tube so as to be circular or annular in shape.
- FIG. 2 there is shown a modified tube 20 having a three-start fin construction providing external fins 21, 22 and 23.
- this external arrangement will provide internal helical grooves 24, 25 and 26.
- this arrangement only one of the grooves; namely, the groove 26, is deepened as illustrated so as to provide the internal helically extending rib 27. Accordingly, the axial spacing Si between adjacent rib convolutions in this case will be three times the axial spacing of the external fins.
- FIG. 3 there is illustrated a tube similar to the tubes previously described except that the fins here generally designated at 32, are the result of a six-start arrangement so that if one of the grooves, as for example the groove 34, is deepened, it produces an internal rib 36 having a pitch or axial spacing Si which is six times as great as the axial spacing Se between adjacent fin convolutions.
- the tube here designated T
- T is advanced over a cylindrical mandrel 40 adapted to support the internal surface of the tube and to maintain it substantially smooth during the fin rolling operation.
- a plurality of fin forming rolls indicated generally at 42, only one of which is illustrated.
- the fin forming rolls comprise an arbor 44 on which a plurality of discs 46 are provided, the discs having a constant axial spacing and being shaped to be rolled into the material of the tubing to produce helical fins 48 and intermediate helical grooves 50.
- the arbor shafts are disposed at the appropriate angle to the axis of the arbor and tube so that each of the discs forms a separate helical groove 50
- FIG. 4 is a six-start helical fin providing a corresponding number of helical grooves 50.
- one of the discs 52 is substantially larger than the remaining discs 46 and is located beyond the end of the mandrel 40 so that the material of the tube opposite the rib forming disc 52 is unsupported. Accordingly, as the tube is advanced over the mandrel as a result of the rotation of the rolls 42, the smaller discs 46 form the fins 48 and the shallow grooves 50, whereas the disc 52 forms the relatively deeper groove 54 and cooperates in the formation of the fins 48 at both sides thereof.
- the disc 52 is required to form the relatively deep groove 54 in its entirety.
- an additional small disc 46 could be provided at the left of the discs illustrated in the figure so that the function of the disc 52 would be merely to deepen a groove 50 previously formed by one of the small discs 46.
- FIG. 5 there is illustrated apparatus for performing a somewhat different fin and rib forming operation on tubing.
- a rolling tool generally designated is provided comprising an arbor 62 on which a plurality of discs 64 are provided, the discs being uniformly spaced by spacers 66.
- the arbor is positioned at an appropriate angle to the tube T so that each of the discs 64 forms a separate distinct helical groove 68, the fins being six in number and also separate and distinct.
- the number of starts which are produced by assembly of finning discs on the tool is determined by the angle at which the arbor is positioned with respect to the axis of the mandrel and tube T.
- the same tool could be employed to produce one, two, three, or six-start fin configurations.
- a separate roll 76 is provided which in this case is positioned with its axis parallel to the axis of the mandrel 72 and tube T.
- the roll 76 is provided with a helical rib 78 extending at a lead or helix angle determined by the lead or helix angle of the grooves 68 on the tube, and further by the relative diameters or circumferences of the tube and the roll or tool 76.
- the rib 78 engages in one of the previously formed grooves 68 and deepens it to the increased depth as indicated at 80, simultaneously producing the radially inwardly prohelical rib. It has previously been indicated that this is desirable because the factors which dictate the most eflicient dimensions, shapes, S/H ratios, etc., of the internal rib are quite different and independent from the factors which dictate the most desirable design of finned exterior. It may be mentioned at this time that one consideration influencing the design of fins at the exterior of the tube is the promotion of drainage of condensate formed on the tube exterior.
- step of rolling one external groove to deepen it is accomplished by positioning a rotary tool having a helical external rib thereon in pressure engagement with the tube at a zone beyond the finishing zone in which the tube is supported by the mandrel.
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Thermal Sciences (AREA)
- Geometry (AREA)
Abstract
Description
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US64866267A | 1967-06-26 | 1967-06-26 | |
US77306568A | 1968-11-04 | 1968-11-04 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3559437A true US3559437A (en) | 1971-02-02 |
Family
ID=27095437
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US773065A Expired - Lifetime US3559437A (en) | 1967-06-26 | 1968-11-04 | Method and apparatus for making heat transfer tubing |
Country Status (1)
Country | Link |
---|---|
US (1) | US3559437A (en) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4438807A (en) * | 1981-07-02 | 1984-03-27 | Carrier Corporation | High performance heat transfer tube |
EP0114640A2 (en) * | 1983-01-25 | 1984-08-01 | Wickes Products, Inc. | Finned heat exchanger tube having optimized heat transfer characteristics |
EP0165583A2 (en) * | 1984-06-20 | 1985-12-27 | Hitachi, Ltd. | Heat transfer tube for single phase flow |
US4866830A (en) * | 1987-10-21 | 1989-09-19 | Carrier Corporation | Method of making a high performance, uniform fin heat transfer tube |
US4915166A (en) * | 1983-08-04 | 1990-04-10 | Wolverine Tube, Inc. | Titanium heat exchange tubes |
US5709029A (en) * | 1992-09-22 | 1998-01-20 | Energy Saving Concepts Limited | Manufacture of helically corrugated conduit |
US5822993A (en) * | 1994-05-13 | 1998-10-20 | Hydrocool Pty Limited | Cooling apparatus |
US20070101749A1 (en) * | 2005-11-09 | 2007-05-10 | Pham Hung M | Refrigeration system including thermoelectric module |
US20070101737A1 (en) * | 2005-11-09 | 2007-05-10 | Masao Akei | Refrigeration system including thermoelectric heat recovery and actuation |
US20100193170A1 (en) * | 2009-02-04 | 2010-08-05 | Andreas Beutler | Heat exchanger tube and method for producing it |
US20120145368A1 (en) * | 2010-12-10 | 2012-06-14 | Uop, Llc | Process for transferring heat or modifying a tube in a heat exchanger |
EP4015958A1 (en) * | 2020-12-17 | 2022-06-22 | Tetra Laval Holdings & Finance S.A. | Corrugated heat transfer pipe |
US12004424B2 (en) | 2019-12-06 | 2024-06-04 | 3M Innovative Properties Company | Flexible thermoelectric device |
-
1968
- 1968-11-04 US US773065A patent/US3559437A/en not_active Expired - Lifetime
Cited By (30)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4438807A (en) * | 1981-07-02 | 1984-03-27 | Carrier Corporation | High performance heat transfer tube |
EP0114640A2 (en) * | 1983-01-25 | 1984-08-01 | Wickes Products, Inc. | Finned heat exchanger tube having optimized heat transfer characteristics |
EP0114640A3 (en) * | 1983-01-25 | 1984-08-15 | Gulf And Western Industries, Inc. | Finned heat exchanger tube having optimized heat transfer characteristics |
US4915166A (en) * | 1983-08-04 | 1990-04-10 | Wolverine Tube, Inc. | Titanium heat exchange tubes |
EP0165583A2 (en) * | 1984-06-20 | 1985-12-27 | Hitachi, Ltd. | Heat transfer tube for single phase flow |
EP0165583A3 (en) * | 1984-06-20 | 1986-10-22 | Hitachi, Ltd. | Heat transfer tube for single phase flow |
US4866830A (en) * | 1987-10-21 | 1989-09-19 | Carrier Corporation | Method of making a high performance, uniform fin heat transfer tube |
US5709029A (en) * | 1992-09-22 | 1998-01-20 | Energy Saving Concepts Limited | Manufacture of helically corrugated conduit |
US5822993A (en) * | 1994-05-13 | 1998-10-20 | Hydrocool Pty Limited | Cooling apparatus |
US20070101739A1 (en) * | 2005-11-09 | 2007-05-10 | Masao Akei | Vapor compression circuit and method including a thermoelectric device |
US8307663B2 (en) | 2005-11-09 | 2012-11-13 | Emerson Climate Technologies, Inc. | Vapor compression circuit and method including a thermoelectric device |
US20070101740A1 (en) * | 2005-11-09 | 2007-05-10 | Masao Akei | Vapor compression circuit and method including a thermoelectric device |
US20070101748A1 (en) * | 2005-11-09 | 2007-05-10 | Pham Hung M | Refrigeration system including thermoelectric module |
US20070101750A1 (en) * | 2005-11-09 | 2007-05-10 | Pham Hung M | Refrigeration system including thermoelectric module |
US20070101749A1 (en) * | 2005-11-09 | 2007-05-10 | Pham Hung M | Refrigeration system including thermoelectric module |
US20070101738A1 (en) * | 2005-11-09 | 2007-05-10 | Masao Akei | Vapor compression circuit and method including a thermoelectric device |
US7278269B2 (en) | 2005-11-09 | 2007-10-09 | Emerson Climate Technologies, Inc. | Refrigeration system including thermoelectric module |
US7284379B2 (en) | 2005-11-09 | 2007-10-23 | Emerson Climate Technologies, Inc. | Refrigeration system including thermoelectric module |
US7310953B2 (en) | 2005-11-09 | 2007-12-25 | Emerson Climate Technologies, Inc. | Refrigeration system including thermoelectric module |
US7752852B2 (en) | 2005-11-09 | 2010-07-13 | Emerson Climate Technologies, Inc. | Vapor compression circuit and method including a thermoelectric device |
US20070101737A1 (en) * | 2005-11-09 | 2007-05-10 | Masao Akei | Refrigeration system including thermoelectric heat recovery and actuation |
US20110120145A1 (en) * | 2005-11-09 | 2011-05-26 | Masao Akei | Vapor Compression Circuit and Method Including A Thermoelectric Device |
US20100193170A1 (en) * | 2009-02-04 | 2010-08-05 | Andreas Beutler | Heat exchanger tube and method for producing it |
US8899308B2 (en) * | 2009-02-04 | 2014-12-02 | Wieland-Werke Ag | Heat exchanger tube and method for producing it |
US20120145368A1 (en) * | 2010-12-10 | 2012-06-14 | Uop, Llc | Process for transferring heat or modifying a tube in a heat exchanger |
US8613308B2 (en) * | 2010-12-10 | 2013-12-24 | Uop Llc | Process for transferring heat or modifying a tube in a heat exchanger |
US20140020875A1 (en) * | 2010-12-10 | 2014-01-23 | Uop Llc | Process for transferring heat or modifying a tube in a heat exchanger |
US9631873B2 (en) * | 2010-12-10 | 2017-04-25 | Uop Llc | Process for transferring heat or modifying a tube in a heat exchanger |
US12004424B2 (en) | 2019-12-06 | 2024-06-04 | 3M Innovative Properties Company | Flexible thermoelectric device |
EP4015958A1 (en) * | 2020-12-17 | 2022-06-22 | Tetra Laval Holdings & Finance S.A. | Corrugated heat transfer pipe |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: WOLVERINE TUBE, INC., A DE. CORP.,ALABAMA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:UOP INC.,;REEL/FRAME:004657/0711 Effective date: 19861027 Owner name: WOLVERINE TUBE, INC., 2100 MARKET STREET, N.E., DE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:UOP INC.,;REEL/FRAME:004657/0711 Effective date: 19861027 |
|
AS | Assignment |
Owner name: BANK OF NOVA SCOTIA, THE, 44 KING STREET, WEST, TO Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:WOLVERINE ACQUISITION CORP. A CORP. OF DE;REEL/FRAME:004696/0897 Effective date: 19870313 |
|
AS | Assignment |
Owner name: WOLVERINE ACQUISITION CORP., A DE CORP,DELAWARE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:WOLVERINE TUBE, INC.,;REEL/FRAME:004728/0083 Effective date: 19870318 Owner name: WOLVERINE ACQUISITION CORP., CORPORATION TRUST CEN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:WOLVERINE TUBE, INC.,;REEL/FRAME:004728/0083 Effective date: 19870318 |
|
AS | Assignment |
Owner name: WOLVERINE TUBE, INC., A CORP. OF AL,ALABAMA Free format text: CHANGE OF NAME;ASSIGNOR:WOLVERINE ACQUISITION CORP.;REEL/FRAME:004827/0237 Effective date: 19870626 Owner name: WOLVERINE TUBE, INC., A CORP. OF AL Free format text: CHANGE OF NAME;ASSIGNOR:WOLVERINE ACQUISITION CORP.;REEL/FRAME:004827/0237 Effective date: 19870626 |