[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

US3589440A - Tube and header construction - Google Patents

Tube and header construction Download PDF

Info

Publication number
US3589440A
US3589440A US881052A US3589440DA US3589440A US 3589440 A US3589440 A US 3589440A US 881052 A US881052 A US 881052A US 3589440D A US3589440D A US 3589440DA US 3589440 A US3589440 A US 3589440A
Authority
US
United States
Prior art keywords
header
tube
wall member
end portions
tube end
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
US881052A
Inventor
Oscar G Friedrich
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.)
Modine Manufacturing Co
Original Assignee
Modine Manufacturing Co
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.)
Filing date
Publication date
Application filed by Modine Manufacturing Co filed Critical Modine Manufacturing Co
Application granted granted Critical
Publication of US3589440A publication Critical patent/US3589440A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/04—Arrangements for sealing elements into header boxes or end plates
    • F28F9/16—Arrangements for sealing elements into header boxes or end plates by permanent joints, e.g. by rolling
    • F28F9/18—Arrangements for sealing elements into header boxes or end plates by permanent joints, e.g. by rolling by welding
    • F28F9/182—Arrangements for sealing elements into header boxes or end plates by permanent joints, e.g. by rolling by welding the heat-exchange conduits having ends with a particular shape, e.g. deformed; the heat-exchange conduits or end plates having supplementary joining means, e.g. abutments
    • 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
    • B21D39/00—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders
    • B21D39/06—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of tubes in openings, e.g. rolling-in
    • 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
    • B21D53/00—Making other particular articles
    • B21D53/02—Making other particular articles heat exchangers or parts thereof, e.g. radiators, condensers fins, headers
    • B21D53/06—Making other particular articles heat exchangers or parts thereof, e.g. radiators, condensers fins, headers of metal tubes
    • 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
    • Y10T29/49389—Header or manifold making

Definitions

  • Stellman and McCord ABSTRACT A tube and header construction which may be used in a cooling radiator for an internal combustion engine in which one end of each tube extends into the header through an opening in a wall member forming a liquid-confining part of the header and with spaced end portions of the tube end within the header being separate from the remainder of the tube and distorted to extend away from this remainder thereby to secure the tube end to the header wall member.
  • these spaced end portions of the tube within the header are curved over until their extreme ends are in contact with the inner surfaces of the wall member.
  • the tube end portions are used to secure a solid joining material such as a brazing material in position to be activated as by melting in a subsequent joining operation where it is in position to bond the tube to the header.
  • One of the features of this invention is to provide a tube and header construction wherein a tube end extends into the header and is provided with spaced separate end portions shaped to extend away from the remainder of the tube end and thereby secure the tube end to the header especially preparatory to permanent joining.
  • FIG. 1 is a fragmentary perspective view of a portion of an internal combustion engine and a cooling radiator therefor including the invention.
  • FIG. 2 is a fragmentary enlarged sectional view through a tube end and the adjacent portion of the header wall illustrating the invention.
  • FIG. 3 is a fragmentary plan view of the structure of FIG. 2 shown in conjunction with a ring of brazing alloy preparatory to joining the tube to the header.
  • FIGS. 4 and 5 are side elevational views of a tool that may be used to produce the tube arrangement of FIGS. 2 and 3.
  • FIG. 1 there is shown an internal combustion engine with a cooling radiator 11 having an inlet header l2 and spaced outlet header 13 for the coolant liquid with the two headers being connected by parallel spaced horizontal coolant tubes 14.
  • the liquid coolant flows in the customary manner from the engine 10 to the inlet header 12 by way of a conduit and after flowing in parallel through the coolant tubes 14 into the outlet header 13 then flows from this header back to the engine 10 by way ofthe radiator 11.
  • the radiator 11 includes the tube and header construction of this invention as illustrated in enlarged detail in FIGS. 2 and 3. As is illustrated there, each tube 14 has an end 16 extending into each header 12 and 13 through a wall member 17 that forms a liquid confining part of the respective header. Thus the wall member 17 in this embodiment will be the inner wall of each of the opposite headers 12 and 13.
  • the tube 14 is of elongated cross section as shown most clearly in FIG. 3 with substantially parallel sides 18.
  • the tube 14 extends through a similarly shaped opening 19 in the wall 17.
  • the tube end portion 16 within the header wall 17 is provided with a pair of oppositely located spaced end portions 20 and 21 each in the form of a tongue separated from the remainder of the tube end 16 by parallel slits 22.
  • each of the end portions 20 and 21 extends away from the remainder of the tube end 16 within its header thereby securing the tube end to the header wall member 17.
  • each end portion 20 and 21 has a terminal edge 23 that is in contact with the inner liquid-contacting'surface 24 of the header wall 17.
  • each end portion 20 and 21 is curved arcuately so as to provide a space between the end portion and the adjacent surface 24 of the header wall 17.
  • this space is utilized to retain a solid joining material such as the illustrated ring 26 of brazing metal alloy in position around the joint between the tube 14 and the header wall 17.
  • a solid joining material such as the illustrated ring 26 of brazing metal alloy
  • the engagement of the ring 26 by the curved end portion 20'and 21 prevents or materially retards the flowing away of the melted alloy from the joint where the alloy is intended to be applied. This of course is the joint between the opening 19 and the adjacent surfaces of the tube 14-.
  • this invention of tube and header construction forms a more secure bonding of the tube to the header both before and after permanent bonding, can be used to hold the bonding metal, either solder or brazing metal, exactly in position where it is needed to form a secure joint and greatly improves the efficiency of mechanical production as it materially reduces and even eliminates failures in the bond which would cause the unit to be rejected.
  • FIGS. 4 and 5 illustrate a tool that may be used to shape the tube end 16.
  • This tool 27 comprises a body 28 with a tapered lower end 29 adapted to fit snugly within the tube end 16. It also has opposite shoulders 30 arcuately curved to engage and bend over the end portions 20 and 21 to the same curvature of the shoulders 30.
  • a tube and header construction comprising: a wall member forming a liquid confining part of said header having an opening; a tube end extending into said header through said opening; and means forming spaced end portions of said tube end within the header extending away from the remainder of said tube end within said header and thereby securing said tube end to said header wall member.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Abstract

A tube and header construction which may be used in a cooling radiator for an internal combustion engine in which one end of each tube extends into the header through an opening in a wall member forming a liquid-confining part of the header and with spaced end portions of the tube end within the header being separate from the remainder of the tube and distorted to extend away from this remainder thereby to secure the tube end to the header wall member. In one embodiment of the invention these spaced end portions of the tube within the header are curved over until their extreme ends are in contact with the inner surfaces of the wall member. In another embodiment the tube end portions are used to secure a solid joining material such as a brazing material in position to be activated as by melting in a subsequent joining operation where it is in position to bond the tube to the header.

Description

United States Patent [72] Inventor Oscar G. Friedrich Sturtevant, Wis. [21] Appl. No. 881,052 [22} Filed Dec. 1, 1969 [45] Patented June 29, 1971 [73] Assignee Modine Manufacturing Company 54] TUBE AND HEADER CONSTRUCTION 7 Claims, 5 Drawing Figs.
[52] 11.5. CI. 165/178, 165/153, 29/1574 [51] Int. Cl F281 9/04 [50} Field oISearch 165/153, 178; 29/157.4
[56] References Cited UNITED STATES PATENTS 2.488.627 11/1949 l-lisey 165/178 X 3,021,804 2/1962 Simpelaar.... 29/1574 X 3.052.452 9/1962 Taga 165/178X Primary Examiner-Frederick L. Matteson Assistant Examiner-Theophil W. Streule Almrney-Hofgren. Wegner. Allen. Stellman and McCord ABSTRACT: A tube and header construction which may be used in a cooling radiator for an internal combustion engine in which one end of each tube extends into the header through an opening in a wall member forming a liquid-confining part of the header and with spaced end portions of the tube end within the header being separate from the remainder of the tube and distorted to extend away from this remainder thereby to secure the tube end to the header wall member. In one embodiment of the invention these spaced end portions of the tube within the header are curved over until their extreme ends are in contact with the inner surfaces of the wall member. In another embodiment the tube end portions are used to secure a solid joining material such as a brazing material in position to be activated as by melting in a subsequent joining operation where it is in position to bond the tube to the header.
PATENTED JUNZQISYI 3589.440
TUBE AND HEADER CONSTRUCTION One of the features of this invention is to provide a tube and header construction wherein a tube end extends into the header and is provided with spaced separate end portions shaped to extend away from the remainder of the tube end and thereby secure the tube end to the header especially preparatory to permanent joining.
Other features and advantages of the invention will be apparent from the following description of one embodiment thereof taken in conjunction with the accompanying drawings. Of the drawings:
FIG. 1 is a fragmentary perspective view of a portion of an internal combustion engine and a cooling radiator therefor including the invention.
FIG. 2 is a fragmentary enlarged sectional view through a tube end and the adjacent portion of the header wall illustrating the invention.
FIG. 3 is a fragmentary plan view of the structure of FIG. 2 shown in conjunction with a ring of brazing alloy preparatory to joining the tube to the header.
FIGS. 4 and 5 are side elevational views of a tool that may be used to produce the tube arrangement of FIGS. 2 and 3.
In FIG. 1 there is shown an internal combustion engine with a cooling radiator 11 having an inlet header l2 and spaced outlet header 13 for the coolant liquid with the two headers being connected by parallel spaced horizontal coolant tubes 14. The liquid coolant flows in the customary manner from the engine 10 to the inlet header 12 by way of a conduit and after flowing in parallel through the coolant tubes 14 into the outlet header 13 then flows from this header back to the engine 10 by way ofthe radiator 11.
The radiator 11 includes the tube and header construction of this invention as illustrated in enlarged detail in FIGS. 2 and 3. As is illustrated there, each tube 14 has an end 16 extending into each header 12 and 13 through a wall member 17 that forms a liquid confining part of the respective header. Thus the wall member 17 in this embodiment will be the inner wall of each of the opposite headers 12 and 13.
In the illustrated embodiment the tube 14 is of elongated cross section as shown most clearly in FIG. 3 with substantially parallel sides 18. The tube 14 extends through a similarly shaped opening 19 in the wall 17. The tube end portion 16 within the header wall 17 is provided with a pair of oppositely located spaced end portions 20 and 21 each in the form of a tongue separated from the remainder of the tube end 16 by parallel slits 22.
Each of the end portions 20 and 21 extends away from the remainder of the tube end 16 within its header thereby securing the tube end to the header wall member 17. In the illus trated embodiment each end portion 20 and 21 has a terminal edge 23 that is in contact with the inner liquid-contacting'surface 24 of the header wall 17. As illustrated in FIG. 2, each end portion 20 and 21 is curved arcuately so as to provide a space between the end portion and the adjacent surface 24 of the header wall 17.
In the embodiment of FIG. 3 this space is utilized to retain a solid joining material such as the illustrated ring 26 of brazing metal alloy in position around the joint between the tube 14 and the header wall 17. When so retained and the assembly heated to brazing temperature in the usual and ordinary brazing operation the engagement of the ring 26 by the curved end portion 20'and 21 prevents or materially retards the flowing away of the melted alloy from the joint where the alloy is intended to be applied. This of course is the joint between the opening 19 and the adjacent surfaces of the tube 14-.
By using the tube and header construction of this invention it is now possible to eliminate the usual deforming of the tube which is the customary way of fixing a tube end to a header wall preparatory to permanent joining. This deforming frequently caused the tube to split and also resulted in uneven spacing of the tube end from the header wall opening through which it extended. The structure of this invention also prevents the tube end becoming filled with brazing metal or solder during the melting joining step.
Thus this invention of tube and header construction forms a more secure bonding of the tube to the header both before and after permanent bonding, can be used to hold the bonding metal, either solder or brazing metal, exactly in position where it is needed to form a secure joint and greatly improves the efficiency of mechanical production as it materially reduces and even eliminates failures in the bond which would cause the unit to be rejected.
FIGS. 4 and 5 illustrate a tool that may be used to shape the tube end 16. This tool 27 comprises a body 28 with a tapered lower end 29 adapted to fit snugly within the tube end 16. It also has opposite shoulders 30 arcuately curved to engage and bend over the end portions 20 and 21 to the same curvature of the shoulders 30.
Having described my invention as related to the embodiment shown in the accompanying drawings, it is my intention that the invention be not limited by any of the details of description, unless otherwise specified, but rather be construed broadly within its spirit and scope as set out in the appended claims.
I claim:
l. A tube and header construction, comprising: a wall member forming a liquid confining part of said header having an opening; a tube end extending into said header through said opening; and means forming spaced end portions of said tube end within the header extending away from the remainder of said tube end within said header and thereby securing said tube end to said header wall member.
2. The structure of claim 1 wherein said tube end is substantially the same size and shape as said opening to fit snugly therein.
3. The structure of claim 1 wherein said end portions have terminal edges in contact with said wall member on the interior of said header.
4. The structure of claim 1 wherein said tube end is of elongated cross section with substantially parallel opposite sides in each of which is located a said end portion.
5. The structure of claim 4 wherein said tube end is substantially the same size and shape as said opening to fit snugly therein, and said end portions have terminal edges in contact with said wall member on the interior of said header.
6. The structure of claim 1 wherein said end portions are spaced from said wall member to retain a solid joining material between the wall member and end portions.
7. The structure of claim 6 wherein said tube end is substantially the same size and shape as said opening to fit snugly therein, and said end portions have terminal edges in contact with said wall member on the interior of said header.

Claims (7)

1. A tube and header construction, comprising: a wall member forming a liquid confining part of said header having an opening; a tube end extending into said header through said opening; and means forming spaced end portions of said tube end within the header extending away from the remainder of said tube end within said header and thereby securing said tube end to said header wall member.
2. The structure of claim 1 wherein said tube end is substantially the same size and shape as said opening to fit snugly therein.
3. The structure of claim 1 wherein said end portions have terminal edges in contact with said wall member on the interior of said header.
4. The structure of claim 1 wherein said tube end is of elongated cross section with substantially parallel opposite sides in each of which is located a said end portion.
5. The structure of claim 4 wherein said tube end is substantially the same size and shape as said opening to fit snugly therein, and said end portions have terminal edges in contact with said wall member on the interior of said header.
6. The structure of claim 1 wherein said end portions are spaced from said wall member to retain a solid joining material between the wall member and end portions.
7. The structure of claim 6 wherein said tube end is substantially the same size and shape as said opening to fit snugly therein, and said end portions have terminal edges in contact with said wall member on the interior of said header.
US881052A 1969-12-01 1969-12-01 Tube and header construction Expired - Lifetime US3589440A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US88105269A 1969-12-01 1969-12-01

Publications (1)

Publication Number Publication Date
US3589440A true US3589440A (en) 1971-06-29

Family

ID=25377683

Family Applications (1)

Application Number Title Priority Date Filing Date
US881052A Expired - Lifetime US3589440A (en) 1969-12-01 1969-12-01 Tube and header construction

Country Status (1)

Country Link
US (1) US3589440A (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4947957A (en) * 1972-04-26 1974-05-09
US3849851A (en) * 1972-09-27 1974-11-26 Tranter Mfg Inc Method of treating welded heat transfer members to eliminate weld scale
US3972371A (en) * 1972-04-26 1976-08-03 Societe Anonyme Des Usines Chausson Tube and tube-plate assembly
US4272006A (en) * 1980-02-01 1981-06-09 Modine Manufacturing Company Method of soldering tube to plate
US4480165A (en) * 1981-12-02 1984-10-30 United Aircraft Products, Inc. Braze fixture and method of using
FR2551853A1 (en) * 1983-09-09 1985-03-15 Ex Cell O Corp HEAT EXCHANGER PROVIDED WITH AN IMPROVED SYSTEM FOR CONNECTING ITS TUBES TO ITS COLLECTORS
US4678112A (en) * 1984-12-04 1987-07-07 Sanden Corporation Method for producing a heat exchanger having a flat tube and header pipes
US5036913A (en) * 1990-11-05 1991-08-06 Valeo Engine Cooling, Incorporated Vehicle radiator with tube to header joint formed of a composite weld and solder bond
EP0457978A1 (en) * 1990-05-04 1991-11-27 Toyo Radiator Co., Ltd. Method for joining heat exchanger tubes with headers
US5101887A (en) * 1990-02-22 1992-04-07 Sanden Corporation Heat exchanger
USRE35098E (en) * 1979-12-20 1995-11-28 Modine Manufacturing Co. Method of making a heat exchanger
EP0772019A1 (en) * 1995-11-02 1997-05-07 Valeo Thermique Moteur S.A. Heat exchanger having tubes of oval or oblong cross section and method of assemling the same
US20020138981A1 (en) * 2001-03-22 2002-10-03 Bernhard Lamich Heat exchanger construction and method
DE102006048484A1 (en) * 2006-10-11 2008-04-17 Behr Gmbh & Co. Kg Heat exchanger with flat tubes and method for producing such a heat exchanger

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2488627A (en) * 1946-02-28 1949-11-22 Young Radiator Co Tube and header-plate assembly for heat-exchange units
US3021804A (en) * 1955-02-18 1962-02-20 Modine Mfg Co Method of fabricating heat exchangers
US3052472A (en) * 1959-05-15 1962-09-04 Aumuller Franz Electrically operable chance game

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2488627A (en) * 1946-02-28 1949-11-22 Young Radiator Co Tube and header-plate assembly for heat-exchange units
US3021804A (en) * 1955-02-18 1962-02-20 Modine Mfg Co Method of fabricating heat exchangers
US3052472A (en) * 1959-05-15 1962-09-04 Aumuller Franz Electrically operable chance game

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3972371A (en) * 1972-04-26 1976-08-03 Societe Anonyme Des Usines Chausson Tube and tube-plate assembly
JPS4947957A (en) * 1972-04-26 1974-05-09
US3849851A (en) * 1972-09-27 1974-11-26 Tranter Mfg Inc Method of treating welded heat transfer members to eliminate weld scale
USRE35098E (en) * 1979-12-20 1995-11-28 Modine Manufacturing Co. Method of making a heat exchanger
US4272006A (en) * 1980-02-01 1981-06-09 Modine Manufacturing Company Method of soldering tube to plate
US4480165A (en) * 1981-12-02 1984-10-30 United Aircraft Products, Inc. Braze fixture and method of using
FR2551853A1 (en) * 1983-09-09 1985-03-15 Ex Cell O Corp HEAT EXCHANGER PROVIDED WITH AN IMPROVED SYSTEM FOR CONNECTING ITS TUBES TO ITS COLLECTORS
DE3432231A1 (en) * 1983-09-09 1985-03-28 Ex-Cell-O Corp., Troy, Mich. HEAT EXCHANGER
US4678112A (en) * 1984-12-04 1987-07-07 Sanden Corporation Method for producing a heat exchanger having a flat tube and header pipes
US5101887A (en) * 1990-02-22 1992-04-07 Sanden Corporation Heat exchanger
EP0457978A1 (en) * 1990-05-04 1991-11-27 Toyo Radiator Co., Ltd. Method for joining heat exchanger tubes with headers
US5036913A (en) * 1990-11-05 1991-08-06 Valeo Engine Cooling, Incorporated Vehicle radiator with tube to header joint formed of a composite weld and solder bond
EP0772019A1 (en) * 1995-11-02 1997-05-07 Valeo Thermique Moteur S.A. Heat exchanger having tubes of oval or oblong cross section and method of assemling the same
FR2740869A1 (en) * 1995-11-02 1997-05-09 Valeo Thermique Moteur Sa HEAT EXCHANGER WITH OVAL OR OBLONG SECTION TUBES AND ITS ASSEMBLY PROCESS
US5901784A (en) * 1995-11-02 1999-05-11 Valeo Thermique Moteur Heat exchanger with oval or oblong tubes, and a method of assembly of such a heat exchanger
US6044554A (en) * 1995-11-02 2000-04-04 Valeo Thermique Moteur Method of assembly of a heat exchanger with oval or oblong tubes
US20020138981A1 (en) * 2001-03-22 2002-10-03 Bernhard Lamich Heat exchanger construction and method
US6971444B2 (en) * 2001-03-22 2005-12-06 Modine Manufacturing Company Heat exchanger construction and method
DE102006048484A1 (en) * 2006-10-11 2008-04-17 Behr Gmbh & Co. Kg Heat exchanger with flat tubes and method for producing such a heat exchanger

Similar Documents

Publication Publication Date Title
US3589440A (en) Tube and header construction
US3689972A (en) Method of fabricating a heat exchanger
US2389175A (en) Method of making heat exchange apparatus
US2270864A (en) Heat exchanger
US2184658A (en) Radiator
US1931467A (en) Radiator
US2509782A (en) Tank fitting and method of making the same
US3708012A (en) Heat exchanger
US2790628A (en) Fabricated fin tube heat exchanger
US1929365A (en) Heat exchange apparatus
US3250323A (en) Heat exchanger
JPH087247Y2 (en) Heat exchanger
JPH02309196A (en) Heat exchanger and manufacture of header
US2228549A (en) Laminated tube plate
US2305992A (en) Heat exchanger
US2226291A (en) Heat exchanger
US2227680A (en) Finned tubing or the like
US1767652A (en) Tube assembly for heat-transfer devices
GB1390782A (en) Heat-exchange tubing
US2028457A (en) Refrigerating apparatus
US4157153A (en) Aluminum tube joint design
US1382607A (en) Manufacture of models
US2278155A (en) Method of making heat exchangers
JP2000018873A5 (en)
US1198307A (en) Tube-sheet and method of forming same.