US3219106A - High-temperature radiator tube design - Google Patents

High-temperature radiator tube design Download PDF

Info

Publication number
US3219106A
US3219106A US89577A US8957761A US3219106A US 3219106 A US3219106 A US 3219106A US 89577 A US89577 A US 89577A US 8957761 A US8957761 A US 8957761A US 3219106 A US3219106 A US 3219106A
Authority
US
United States
Prior art keywords
tube
end portions
shield
shields
sections
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
US89577A
Inventor
John E Ahern
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.)
Raytheon Technologies Corp
Original Assignee
United Aircraft Corp
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 United Aircraft Corp filed Critical United Aircraft Corp
Priority to US89577A priority Critical patent/US3219106A/en
Application granted granted Critical
Publication of US3219106A publication Critical patent/US3219106A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00Tubular elements; Assemblies of tubular elements
    • F28F1/08Tubular elements crimped or corrugated in longitudinal section
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00Tubular elements; Assemblies of tubular elements
    • F28F1/003Multiple wall conduits, e.g. for leak detection
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00Tubular elements; Assemblies of tubular elements
    • F28F1/10Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
    • F28F1/12Tubular 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
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F19/00Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F21/00Constructions of heat-exchange apparatus characterised by the selection of particular materials
    • F28F21/08Constructions of heat-exchange apparatus characterised by the selection of particular materials of metal
    • F28F21/081Heat exchange elements made from metals or metal alloys
    • F28F21/082Heat exchange elements made from metals or metal alloys from steel or ferrous alloys
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28DHEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/0054Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for nuclear applications
    • YGENERAL 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
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S165/00Heat exchange
    • Y10S165/903Convection
    • YGENERAL 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
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S165/00Heat exchange
    • Y10S165/905Materials of manufacture

Definitions

  • Tubes used in such a high-temperature environment must have high strength at elevated temperatures in order to take all pressure loads. Tubes made of columbium and molybdenum are typical for this application. These materials while exhibiting high strength at high temperatures are subject to catastrophic oxidation at elevated temperatures and must be protected on the air side.
  • FIG. 1 is a side elevation, partly in section, of an end portion of a radiator tube embodying this invention
  • FIG. 4 is a longitudinal, sectional view showing the arrangement of intermediate support areas for the tube.
  • the radiator tube is made of some suitable material such as columbium or molybdenum. These materials are typical for this application and are capable of resisting elevated temperatures without losing their ability to take the necessary pressure loads.
  • a series of circumferential axially extended grooves 12 are provided in the outer surface of the tube to provide extended surface on the air side of the tube.
  • the grooved sections are separated by ungrooved portions, or lands, 14, one of which is located at each end of the tube and several of which are located intermediate the tube ends. If the tube does not need support intermediate its ends, the grooves can be continuous except at the ends.
  • each tube is completely surrounded either by a continuous tubular shield 16 or a plurality of short connected shields.
  • Each shield has a corrugated section 18 comprising relatively deep annular corrugations and uncorrugated end portions 20 which fit closely over the outside diameter of tube 10 at the ungrooved portions thereof.
  • the end portions 20 of adjacent shields meet, or very nearly meet, leaving only suflicient space to make 3,219,1fi6 Patented Nov. 23, 1965 the brazed joint between them and the underlying tube 10.
  • the corrugations at their inner diameter are in direct contact with the outside diameter of the tube 10.
  • This shield may be made of stainless steel, Monel, Inconel X, or any other suitable material, which can resist oxidation at high temperatures.
  • each shield is either brazed or welded to the smooth annular lands 14 of tube 10 so as to make a fluid-tight seal thereat, and the space between the grooved portion of tube 10 and the corrugated section of the shield is filled with a suitable inert gas to protect the tube from oxidation.
  • a wear sleeve 22 may be provided over each ungrooved portion 14 of tube 10, as shown in FIGS. 3 and 4, if the tube is so long that it needs support intermediate its ends. This sleeve is brazed or welded to the end portions 20 of adjacent shields, as shown in FIG. 4.
  • headers 24 are provided into which the tubes 10 extend and to which the tubular end portions 20 of the adjacent shields also extend and to which they are both welded or brazed.
  • the corrugated shields are able to slide freely longitudinally of the tube with unrestricted movement due to forces set up by expansion and contraction.
  • the heat-flow pattern is particularly advantageous. Heat is transferred from the liquid metal inside the tube 10 to the tube wall by convection, and then through the tube wall and through the fins provided by the longitudinal grooves by conduction. Heat is transferred from the exterior grooved surface to the interior shield surface by radiation. Conductor resistance through the shield itself will be small and heat will be transferred from the shield exterior to the air by convection.
  • the use of radiant-heat transfer from the exterior grooved surface to the shield is particularly attractive since radiant heattransfer rates increase as a fourth power of the temperature level and thus are significant at elevated temperatures in the range of 1600 F. to 2000 F.
  • the corrugated shield may be continuous from heater-to-header in some radiators rather than being built in sections as illustrated herein.
  • a tube structure for use in a high-temperature liquid-meta l-to-air radiator, spaced headers, a plurality of tubes extended between said headers, each tube having a plurality of longitudinally grooved sections separated by ungrooved annular lands, and means for protecting said '3 tubes against oxidation comprising tubular shields on each tube extended from header-to-header, said shields being made in sections, each section including smooth cylindrical end portions which overlie and are bonded in fluid-tight manner to adjacent lands and a corrugated portion intermediate said end portions having annular corrugations which overlie a grooved section of said tube.
  • a tube structure as claimed in claim 1 having a body of inert gas sealed in the spaces between said grooved sections of said tube and said corrugated portions of said shields.
  • a tube for use in a high-temperature liquid-metal-toair radiator comprising a continuous length formed of a material having high strength at elevated temperatures and having outer extended surfaces in the form of longitudinal grooves, said grooves being arranged in a plurality of longitudinally spaced circumferential bands which are separated by ungrooved cylindrical lands, and means for protecting said tube from oxidation on its outer air side throughout its alternate grooved and ungrooved portions comprising a plurality of cylindrical shield sections strung on said tube end-to-end along its length, said shield sections having continuous annular corrugations transverse to and longitudinally coextensive with the grooves in said bands and smooth cylindrical end portions coinciding with the lands on said tube, adjacent end portions of adjacent sections engaging closely a land on said tube to which they are sealed in a fluid-tight manner, and a body of inert gas in the space between each shield section and said tube.
  • a tube according to claim 4 inwhich the adjacent end portions of adjacent shield sections are enclosed by a wear sleeve which is bonded thereto.

Description

Nov. 23, 1965 J. E. AHERN HIGH-TEMPERATURE RADIATOR TUBE DESIGN Filed Feb. 14, 1961 IIIIIIIIII' v. 1,1,11,11,14 wag N IIIIIIIIIIIII INVENTOR JOHN E. AHERN w. a. M
A T TORNEV United States Patent 3,219,106 HIGH-TEMPERATURE RADIATOR TUBE DESIGN John E. Ahcrn, Granada Hills, Califi, assignor to United Aircraft Corporation, East Hartford, Conn., a corporation of Delaware Filed Feb. 14, 1961, Ser. No. 89,577 6 Claims. (Cl. 165-134) This invention relates to high-temperature heat ex changers such, for example, as liquid-metal-to-air radiators, and is particularly concerned with an extended-surface tube element for use in such radiators.
The tubes used in such a high-temperature environment must have high strength at elevated temperatures in order to take all pressure loads. Tubes made of columbium and molybdenum are typical for this application. These materials while exhibiting high strength at high temperatures are subject to catastrophic oxidation at elevated temperatures and must be protected on the air side.
It has been proposed to clad, or coat, the base material, but this has the disadvantage of creating excessive stress due to differential expansion when thermal cycling or thermal shocking the radiator. The resulting stress will cause failure in either the protective cladding or the base metal.
It is an object of this invention to provide an oxidationresistant shield for a tube of a radiator for high-temperature application on the air side of the radiator tube.
A further object of the invention is to provide additional surface per unit length of a radiator tube to increase the air-side heat-transfer rate. This is important in liquid-metal-to-air heat exchangers where the air-side heat-transfer coefficient is so much lower than the liquid side.
A still further object of the invention is generally to improve radiators for use at high temperatures.
These and other advantages and objects of the invention will be evident or will be pointed out in connection with the following description of one embodiment of the invention shown in the accompanying drawings. In these drawings:
FIG. 1 is a side elevation, partly in section, of an end portion of a radiator tube embodying this invention;
FIG. 2 is a transverse section taken on line 22 of FIG. 1;
FIG. 3 is a View of the improved tube installed in a radiator; and
FIG. 4 is a longitudinal, sectional view showing the arrangement of intermediate support areas for the tube.
Referring to the drawings, the radiator tube is made of some suitable material such as columbium or molybdenum. These materials are typical for this application and are capable of resisting elevated temperatures without losing their ability to take the necessary pressure loads. A series of circumferential axially extended grooves 12 are provided in the outer surface of the tube to provide extended surface on the air side of the tube. The grooved sections are separated by ungrooved portions, or lands, 14, one of which is located at each end of the tube and several of which are located intermediate the tube ends. If the tube does not need support intermediate its ends, the grooves can be continuous except at the ends.
In order to prevent catastrophic oxidation at elevated temperatures, each tube is completely surrounded either by a continuous tubular shield 16 or a plurality of short connected shields. Each shield has a corrugated section 18 comprising relatively deep annular corrugations and uncorrugated end portions 20 which fit closely over the outside diameter of tube 10 at the ungrooved portions thereof. The end portions 20 of adjacent shields meet, or very nearly meet, leaving only suflicient space to make 3,219,1fi6 Patented Nov. 23, 1965 the brazed joint between them and the underlying tube 10. As shown in FIG. 1, the corrugations at their inner diameter are in direct contact with the outside diameter of the tube 10. This shield may be made of stainless steel, Monel, Inconel X, or any other suitable material, which can resist oxidation at high temperatures.
The end portions 20 of each shield are either brazed or welded to the smooth annular lands 14 of tube 10 so as to make a fluid-tight seal thereat, and the space between the grooved portion of tube 10 and the corrugated section of the shield is filled with a suitable inert gas to protect the tube from oxidation.
A wear sleeve 22 may be provided over each ungrooved portion 14 of tube 10, as shown in FIGS. 3 and 4, if the tube is so long that it needs support intermediate its ends. This sleeve is brazed or welded to the end portions 20 of adjacent shields, as shown in FIG. 4.
At the ends of the tubes, headers 24 are provided into which the tubes 10 extend and to which the tubular end portions 20 of the adjacent shields also extend and to which they are both welded or brazed.
With this construction the tubes 10 are completely enclosed by the headers and the shields, and oxidation on the air side of the tube is avoided. The corrugated shields are able to slide freely longitudinally of the tube with unrestricted movement due to forces set up by expansion and contraction. The heat-flow pattern is particularly advantageous. Heat is transferred from the liquid metal inside the tube 10 to the tube wall by convection, and then through the tube wall and through the fins provided by the longitudinal grooves by conduction. Heat is transferred from the exterior grooved surface to the interior shield surface by radiation. Conductor resistance through the shield itself will be small and heat will be transferred from the shield exterior to the air by convection. The use of radiant-heat transfer from the exterior grooved surface to the shield is particularly attractive since radiant heattransfer rates increase as a fourth power of the temperature level and thus are significant at elevated temperatures in the range of 1600 F. to 2000 F.
From the above description it will be evident that means has been provided for protecting radiator tubes from oxidation on the air side while avoiding the disadvantages of cladding or coating which has been the practice hereto. It will also be evident that additional surface per unit length of the tube has been provided on the air side to increase air-side heat-transfer rate which is desirable in liquid-metal-to-air heat exchangers where the air-side heattransfer coefficient is very much lower than the coefficient on the liquid side.
It will also be evident that the construction of this invention avoids stresses in the tube structure from stresses set up by expansion and contraction due to differences in temperature in the liquid metal and in the air. Also, means has been provided between the corrugated sections of the tube shield to provide intermediate tube-support areas if they should be required in a long tube.
While only one embodiment of the invention has been shown herein, it will be evident that various changes in the construction and arrangements of the parts may be resorted to without departing from the scope of the invention as defined by the claims; for example, the corrugated shield may be continuous from heater-to-header in some radiators rather than being built in sections as illustrated herein.
I claim:
1. In a tube structure for use in a high-temperature liquid-meta l-to-air radiator, spaced headers, a plurality of tubes extended between said headers, each tube having a plurality of longitudinally grooved sections separated by ungrooved annular lands, and means for protecting said '3 tubes against oxidation comprising tubular shields on each tube extended from header-to-header, said shields being made in sections, each section including smooth cylindrical end portions which overlie and are bonded in fluid-tight manner to adjacent lands and a corrugated portion intermediate said end portions having annular corrugations which overlie a grooved section of said tube.
2. A tube structure as claimed in claim 1 having wear sleeves surrounding the adjacent end portions of adjacent shields and bonded thereto in a fluid-tight manner.
3. A tube structure as claimed in claim 1 having a body of inert gas sealed in the spaces between said grooved sections of said tube and said corrugated portions of said shields.
4. A tube for use in a high-temperature liquid-metal-toair radiator, said tube comprising a continuous length formed of a material having high strength at elevated temperatures and having outer extended surfaces in the form of longitudinal grooves, said grooves being arranged in a plurality of longitudinally spaced circumferential bands which are separated by ungrooved cylindrical lands, and means for protecting said tube from oxidation on its outer air side throughout its alternate grooved and ungrooved portions comprising a plurality of cylindrical shield sections strung on said tube end-to-end along its length, said shield sections having continuous annular corrugations transverse to and longitudinally coextensive with the grooves in said bands and smooth cylindrical end portions coinciding with the lands on said tube, adjacent end portions of adjacent sections engaging closely a land on said tube to which they are sealed in a fluid-tight manner, and a body of inert gas in the space between each shield section and said tube.
5. A tube constructed in accordance with claim 4 in which the small diameter of the corrugations of the shield sections rest on the extremities of the outer grooved surface of the tube.
6. A tube according to claim 4 inwhich the adjacent end portions of adjacent shield sections are enclosed by a wear sleeve which is bonded thereto.
References Cited by the Examiner UNITED STATES PATENTS 1,218,895 3/1917 Porter.
1,495,066 5/ 1924 Browne.
1,920,365 8/1933 Del Mar 257-424 2,155,383 4/1939 Carr 257262.1 X 2,440,245 4/ 1948 Chevigny.
2,686,864 8/1954 Wroughton et al. 207--10.11 X 2,755,925 7/1956 Boccon-Gibod et al. 20710.11 X
ROBERT A. OLEARY, Primary Examiner.
ARTHUR M. HORTON, Examiner.

Claims (1)

1. IN A TUBE STRUCTURE FOR USE IN A HIGH-TEMPERATURE LIQUID-METAL-TO-AIR RADIATOR, SPACED HEADERS, A PLURALITY OF TUBES EXTENDED BETWEEN SAID HEADERS, EACH TUBE HAVING A PLURALITY OF LONGITUDINALLY GROOVED SECTIONS SEPARATED BY UNGROOVED ANNULAR LANDS, AND MEANS FOR PROTECTING SAID TUBES AGAINST OXIDATION COMPRISING TUBULAR SHIELDS ON EACH TUBE EXTENDED FROM HEADER-TO-HEADER, SAID SHIELDS BEING MADE IN SECTIONS, EACH SECTION INCLUDING SMOOTH CYLINDRICAL END PORTIONS WHICH OVERLIE AND ARE BONDED IN FLUID-TIGHT MANNER TO ADJACENT LANDS AND A CORRUGATED PORTION INTERMEDIATE SAID END PORTIONS HAVING ANNULAR CORRUGATIONS WHICH OVERLIE A GROOVED SECTION OF SAID TUBE.
US89577A 1961-02-14 1961-02-14 High-temperature radiator tube design Expired - Lifetime US3219106A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US89577A US3219106A (en) 1961-02-14 1961-02-14 High-temperature radiator tube design

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US89577A US3219106A (en) 1961-02-14 1961-02-14 High-temperature radiator tube design

Publications (1)

Publication Number Publication Date
US3219106A true US3219106A (en) 1965-11-23

Family

ID=22218410

Family Applications (1)

Application Number Title Priority Date Filing Date
US89577A Expired - Lifetime US3219106A (en) 1961-02-14 1961-02-14 High-temperature radiator tube design

Country Status (1)

Country Link
US (1) US3219106A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5126553U (en) * 1974-08-19 1976-02-26
US4326871A (en) * 1980-02-11 1982-04-27 Manville Service Corporation Cooling tubes for glass filament production apparatus
US4397665A (en) * 1980-02-11 1983-08-09 Manville Service Corporation Cooling tubes for glass filament production apparatus
EP0108525A1 (en) * 1982-11-03 1984-05-16 Thermodynetics, Inc. Heat exchanger

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1218895A (en) * 1914-02-10 1917-03-13 Edwin H Porter Pipe for the conveyance of fluids.
US1495066A (en) * 1921-07-18 1924-05-20 Barber Asphalt Paving Co Jacketed conduit
US1920365A (en) * 1931-08-15 1933-08-01 Mar Harry Del Radiator
US2155383A (en) * 1935-12-02 1939-04-25 Pure Oil Co Method and apparatus for transferring heat
US2440245A (en) * 1944-03-13 1948-04-27 Standard Telephones Cables Ltd Cooling of high-temperature bodies
US2686864A (en) * 1951-01-17 1954-08-17 Westinghouse Electric Corp Magnetic levitation and heating of conductive materials
US2755925A (en) * 1952-02-26 1956-07-24 Pechiney Prod Chimiques Sa Extrusion of metals

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1218895A (en) * 1914-02-10 1917-03-13 Edwin H Porter Pipe for the conveyance of fluids.
US1495066A (en) * 1921-07-18 1924-05-20 Barber Asphalt Paving Co Jacketed conduit
US1920365A (en) * 1931-08-15 1933-08-01 Mar Harry Del Radiator
US2155383A (en) * 1935-12-02 1939-04-25 Pure Oil Co Method and apparatus for transferring heat
US2440245A (en) * 1944-03-13 1948-04-27 Standard Telephones Cables Ltd Cooling of high-temperature bodies
US2686864A (en) * 1951-01-17 1954-08-17 Westinghouse Electric Corp Magnetic levitation and heating of conductive materials
US2755925A (en) * 1952-02-26 1956-07-24 Pechiney Prod Chimiques Sa Extrusion of metals

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5126553U (en) * 1974-08-19 1976-02-26
US4326871A (en) * 1980-02-11 1982-04-27 Manville Service Corporation Cooling tubes for glass filament production apparatus
US4397665A (en) * 1980-02-11 1983-08-09 Manville Service Corporation Cooling tubes for glass filament production apparatus
EP0108525A1 (en) * 1982-11-03 1984-05-16 Thermodynetics, Inc. Heat exchanger

Similar Documents

Publication Publication Date Title
US3053283A (en) Duct assemblies
US3512581A (en) Cryogenic devices
US4346643A (en) Thermal jacket for elongated structures
US3363680A (en) Plastic tube heat exchanger with novel header construction
ES2380285T3 (en) Insulation element for hot gas transport duct and procedure for carrying out such duct
US3705734A (en) Arrangement for compensating for changes in the length of pipes and the like
US2707493A (en) Conduits
US3132691A (en) Heat exchanger construction and thermal shield therefor
US4259993A (en) Ceramic-insulated pipe for the transport of hot fluids
US2937036A (en) High temperature telescopic joint with heat insulating and radiating means
US5472047A (en) Mixed finned tube and bare tube heat exchanger tube bundle
US3219106A (en) High-temperature radiator tube design
US3398527A (en) Corrugated wall radiation cooled combustion chamber
US3854528A (en) Heat-exchanger module
GB1136292A (en) Improvements in or relating to cross-counterflow heat exchangers
US3630274A (en) Heat exchanger provided with a thermal barrier
US3610324A (en) Air cooler apparatus
US3177935A (en) Cooling tube structure
IL22389A (en) Heat exchanger
US3270780A (en) Composite heat exchanger tube structure
US3317223A (en) Multiple expansion joint
JP2021050776A (en) Corrugated piping, and cooling piping with thermal contraction relaxation mechanism
IL24059A (en) Tubular fuel pencil for nuclear reactors
US3283811A (en) Spur tube heat exchanger
US3400757A (en) Tubular heat exchanger with elastomeric outer sleeve