US20040104009A1 - Arrangement in a pipe joint for a heat exchanger - Google Patents

Arrangement in a pipe joint for a heat exchanger Download PDF

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Publication number
US20040104009A1
US20040104009A1 US10/707,125 US70712503A US2004104009A1 US 20040104009 A1 US20040104009 A1 US 20040104009A1 US 70712503 A US70712503 A US 70712503A US 2004104009 A1 US2004104009 A1 US 2004104009A1
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US
United States
Prior art keywords
pipe
section
heat exchanger
deformable
recited
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.)
Abandoned
Application number
US10/707,125
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English (en)
Inventor
Max Xie
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.)
Rekuperator Svenska AB
Original Assignee
Rekuperator Svenska AB
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 Rekuperator Svenska AB filed Critical Rekuperator Svenska AB
Assigned to REKUPERATOR SVENSKA AB reassignment REKUPERATOR SVENSKA AB ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: XIE, MAX
Publication of US20040104009A1 publication Critical patent/US20040104009A1/en
Abandoned legal-status Critical Current

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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
    • F28F9/0246—Arrangements for connecting header boxes with flow lines
    • 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
    • F28F9/0236—Header boxes; End plates floating elements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D21/0001—Recuperative heat exchangers
    • F28D21/0003—Recuperative heat exchangers the heat being recuperated from exhaust gases
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2265/00—Safety or protection arrangements; Arrangements for preventing malfunction
    • F28F2265/26—Safety or protection arrangements; Arrangements for preventing malfunction for allowing differential expansion between elements

Definitions

  • the present invention relates to an arrangement in a pipe joint for a heat exchanger also termed a recuperator that is adapted for use with a gas turbine for stationary use in a small scale combined power and heating plant or for mobile use in a vehicle.
  • a heat exchanger of the type may be used in, for example, a combined power and heating plant, for mobile use or in a reserve power station.
  • the recuperator may, for instance, be made up of a plate heat exchanger comprising a number of plates manufactured from very thin sheet metal, generally having a thickness of about 0.1 mm.
  • the plates are provided with corrugations in a known manner, whereby they are stabilized relative to each other in a wave shaped pattern. Spaces between the corrugations will then form flow channels for a heat emitting medium and a heat-absorbing medium. If a gas turbine is used, the heat-emitting medium is combusted gases leaving the turbine, while the heat-absorbing medium is usually air.
  • the heat emitting and absorbing media may have a relatively high temperature, problems may arise in tubing and pipe joints of such systems.
  • the temperature in the component parts will rise from ambient temperature, for example 20° C., to temperatures in excess of 600° C. This usually entails large thermal loading due to heat expansion in different parts of the system. In operation the variations in temperature between different parts of the plant are less, but may still cause problems.
  • FIG. 2 One solution, though deficient, is shown in FIG. 2 that includes an inlet pipe connection 2 for conducting a heat emitting medium 6 to the heat exchanger.
  • the combusted exhaust gas at a temperature of about 650° C. and a pressure of about 1.1 bars, is conducted from a gas turbine to the inlet pipe connection 2 and into the heat exchanger.
  • a heat absorbing medium 7 such as air, is heated by the exhaust gases, whereby the air leaves the heat exchanger through the outlet pipe connection 3 at a temperature of about 610° C. and a pressure of 4 bar.
  • the lower end A of the inlet pipe connection 2 is mounted with a force fit onto a corresponding recess in a flange on the heat exchanger.
  • the lower end A can be provided with a number of radial grooves C around its periphery, in order to increase the contact pressure between said end and the recess B.
  • the grooves C may also be provided with sealing devices of suitable kind. Thermal loading caused by, for instance, axial expansion of the inlet pipe connection must be absorbed by the joint, therefore the component parts must be movable relative to each other.
  • the arrangement may also have a certain leakage flow L F between the inlet and outlet parts.
  • the leakage flow is partly due to the pressure difference and partly due to poor fitting and relative movement between the component parts. Such a leakage will lower the efficiency of the heat exchanger.
  • a further problem is the fit of such a pipe joint between two fixed points, where variations in fit and tolerance between the component parts of the heat exchanger may sometimes occur. In such cases it is also desirable to have a pipe joint that is deformable in several directions.
  • the purpose of the current invention is to eliminate problems associated with known solutions, thereby fulfilling the desired objectives of an improved pipe arrangement for a heat exchanger, as well as providing a simple and inexpensive arrangement for this purpose.
  • the purpose(s) of the invention are achieved by means of a pipe arrangement for heat exchangers and relating to pipe joint(s) for the heat exchanger which comprises (includes, but it not limited to) a number of corrugated plates.
  • Each plate has a first edge part opposite a second edge part and a third edge part opposite a fourth edge part.
  • first and second flow channels Between the corrugated plates there are provided first and second flow channels, where a heat emitting medium flows through every alternate channel and a heat absorbing medium flows through every other alternate channel.
  • a collecting channel for heat emitting medium which channel has a diverging cross-section, is placed at one side of the heat exchanger and is provided with an inlet section connected to a combined inlet and outlet pipe connection for the heat emitting and heat absorbing media.
  • an outgoing collection channel for the heat-absorbing medium is arranged on the same side of the heat exchanger and has an outlet section connected to the inlet and outlet pipe.
  • the inlet pipe comprises a deformable first pipe section, arranged to absorb thermal and mechanical movements in both axial and radial directions, and at least one further pipe section.
  • the deformable section is preferably, but not necessarily, elastically deformable.
  • the heat exchanger can co-operate with a gas turbine, whereby its combusted exhaust gases are used as the heat-emitting medium.
  • the inlet pipe connection has a deformable first pipe section made up of a substantially cylindrical pipe, with walls having a corrugated cross-section in the axial direction of the pipe.
  • a deformable first pipe section made up of a substantially cylindrical pipe, with walls having a corrugated cross-section in the axial direction of the pipe.
  • the average diameter that is the average of the inner and outer diameters of the corrugations, should be larger than the inner diameter of the adjoining second pipe section.
  • the inner diameter of the deformable first pipe section corresponding to the smallest diameter of the corrugated section, is equal to the inner diameter of the second pipe section.
  • the cross-section of the corrugated section may be varied depending on the size and direction of the thermal movements to be absorbed.
  • a suitable shape is a sinusoidal cross-section, where the amplitude and wavelength can be varied to give the desired properties with respect to deformability in the axial and radial directions.
  • the first pipe section is preferably elastically deformable.
  • the inlet and outlet pipe joints are arranged concentrically, it is further possible to distribute the flow losses between inlet and outlet.
  • the average diameter of the corrugated section that is the average of the inner and outer diameters of the corrugations, can be equal to the inner diameter of the adjoining second pipe section.
  • a corrugated section as described above can be manufactured, for instance, by means of rolling, for metallic materials, injection molding, for plastic materials, or winding, for composite material.
  • the resistance to deformation of the first pipe section is decided by the relative axial distance and radial amplitude of the corrugations, as well as the material thickness. These variables are selected with respect to the desired diameter of the pipes, the maximum deformation caused by thermal loading, and the temperatures and pressures to be handled by the pipes. Deformation of the corrugated section in its axial direction will mainly occur during changes of temperature in connection with start-up and operation of the plant, while deformation in its radial direction will mainly occur during assembly and fitting of the pipe joint.
  • the pipe section By making the pipe section elastically deformable, it will be able to absorb movements in the same way as a spring. Hence the section will absorb movements between the pipes without transmitting forces to any greater extent.
  • the material thickness of the deformable first pipe section should be equal to or less than the thickness of the other pipe sections. If the sections have a material thickness of 1 mm, the corrugated section may have a material thickness of 0.3-0.6 mm. The selected thicknesses and the relation therebetween is of course dependent on the size of the thermal movements, the dimensions of the pipes, the pressure of the flowing media and similarly related factors.
  • the second pipe section of the inlet pipe has a cylindrical basic shape.
  • the deformable section may be attached to the cylindrical pipe section upstream or downstream relative to the direction of flow. If the deformable section is placed downstream of the cylindrical section, then it is directly attached, preferably welded, to the collection channel going into the heat exchanger. If the pipe assembly includes a further, third cylindrical pipe section, then the deformable section may be attached in-between the second and the third pipe section.
  • the second pipe section has a conical basic shape.
  • the deformable section may be attached to the conical pipe section upstream or downstream in the direction of flow. If the deformable section is placed downstream of the conical section, then it is directly attached, preferably welded, to the collection channel going into the heat exchanger.
  • the conical pipe section is arranged to diverge in the direction of flow, whereby the diameter of the respective inlet and outlet is selected with respect to the flow rate, pressure or outlet velocity of the flow, and/or other related and desirable parameters.
  • the combined inlet and outlet pipe joint is made up of two concentric pipes.
  • the outer pipe joint may either have a cylindrical or conical cross-section. Both these embodiments of the outer pipe joint can be combined with any one of the embodiments of the inner pipe joint described above.
  • the average diameter of the corrugated section, as defined above, is preferably equal to the diameters of the adjoining pipe sections.
  • the material used for constructing the pipe arrangement is best chosen with respect to the field of application of the heat exchanger; that is, the type of heat emitting and absorbing medium, and the temperatures and pressure to which the pipe arrangement will be subjected.
  • High temperatures and pressures will preferably require metallic materials, such as steel or aluminum of suitable thickness and quality, while lower temperatures and pressures may allow the use of plastic pipes. Corrosive media may require particularly resistant materials.
  • Joining of metallic pipes is preferably done by welding or soldering, while plastic materials and composites may be joined by welding, melting or gluing.
  • Mechanical connections, such as threaded connections, are also possible, but will at the same time give a more space consuming, complex and therefore more expensive solution.
  • FIG. 1 is a cross-sectional view showing schematically a recuperator, provided with a combined inlet and outlet pipe joint configured according to the present invention
  • FIG. 2 is a cross-sectional view showing a pipe connection of known configuration
  • FIG. 3 is a cross-sectional view showing an alternative embodiment of the invention.
  • FIG. 4 is a cross-sectional view showing a further alternative embodiment of the invention.
  • FIG. 1 shows a schematic representation of a recuperator comprising a heat exchanger packet 1 with a combined inlet and outlet pipe joint 2 , 3 , and a outgoing, first collection channel 4 with a pipe connection 5 between the collection channel and the outlet pipe joint 3 .
  • the combined inlet and outlet pipe joint 2 , 3 comprises two concentric pipes forming channels for heat transporting media.
  • the inner inlet pipe joint 2 is connected to a source of heat emitting medium, which in this illustrative case is combusted exhaust gas from a gas turbine which has not been shown.
  • the mass flow of heat-emitting medium 6 flows through the heat exchanger in which a large portion of its heat energy is emitted to a heat-absorbing medium, which in this case is air.
  • the heat-absorbing medium is collected in the outgoing, first collection channel 4 , whereby the flow 7 is directed out through a pipe connection 5 to the outlet pipe joint 3 towards the gas turbine.
  • the combined inlet and outlet joint comprises two concentric, partially conical channels.
  • the inner pipe section, or the inlet pipe joint 2 is welded to an incoming, second collection channel 8 in the form of a diverging section or flange, which in turn is attached to an upper casing 9 on the heat exchanger 1 .
  • the upper casing 9 conducts the heat-emitting medium in the direction of the flow channels (not shown) of the heat exchanger.
  • a deformable pipe section 10 is attached to the inlet of the inner pipe section 2 and will be described in further detail in connection with FIG. 4 below.
  • the outer pipe section 3 is attached to the flange 8 at its inlet end, facing the heat exchanger, and to a not shown casing surrounding the gas turbine at its opposite end.
  • FIG. 3 shows an alternative embodiment of a pipe connection.
  • the combined inlet and outlet joint comprises a pair of concentric, cylindrical inner and outer pipe sections 2 , 3 .
  • the inlet pipe joint 2 includes a deformable, substantially cylindrical, first pipe section 10 , attached between a cylindrical second pipe section 2 a and a cylindrical third pipe section 2 b .
  • the cylindrical second pipe section 2 a is provided with a flange 11 for connecting it to a heat source, in this case a gas turbine (not shown), while the cylindrical third pipe section 2 b is welded to the flange 8 .
  • the deformable first pipe section has an inner diameter, D 1 , corresponding to the smallest diameter of the corrugated section 10 , which is equal to the inner diameter D 2 of the second section.
  • D 1 the inner diameter of the corrugated section 10
  • D 2 the inner diameter of the second section.
  • the first pipe section 10 is provided with flanges 10 a , 10 b on either side of the corrugated section, which flanges are in contact with and welded to the outer periphery of the second and third section 2 a , 2 b respectively.
  • the temperature of the pipe joint will rise from a relatively low temperature, such as 20° C., to an operating temperature in excess of 600° C.
  • the axial movement of the inner pipe section, in connection with thermal expansion of the material, to the extent it differs from that of the outer pipe section, will be taken up by the deformable pipe section 10 .
  • the outer pipe joint 3 has a cylindrical basic shape along its outer periphery. However, it is slightly conical along its inner periphery, as the inner surface is coated with an insulating material 12 with a gradually increasing thickness. The reason for this is to minimize heat loss from the medium flowing in the direction of the gas turbine.
  • the conical shape will also give certain flow-related advantages.
  • FIG. 3 shows a deformable section 10 having a cylindrical section 2 a , 2 b on either side. It is, however, possible to eliminate one of these cylindrical sections, whereby the deformable section is placed at one end of a cylindrical pipe section.
  • FIG. 4 shows a further alternative embodiment in the form of a pipe connection.
  • the combined inlet and outlet pipe joint comprises a pair of conical inner and outer pipe sections 2 , 3 .
  • the inner pipe section is provided with a deformable, substantially cylindrical first pipe section 10 attached to a cylindrical second pipe section.
  • the cylindrical first pipe section is provided with a flange 11 for connection to a heat source, in this case a gas turbine (not shown), while the conical second pipe section is attached to the flange 8 .
  • the deformable first pipe section has an inner diameter D 1 , corresponding to the smallest inner diameter of the corrugated section, which is equal to the inner diameter D 2 of the adjoining second section.
  • the first pipe section 10 is provided with flanges 10 a , 10 b on either side of the corrugated section, which flanges are in contact with and welded to the outer periphery of the second pipe section 2 and the flange 11 , respectively.
  • the inner surface of the outer pipe section is coated with an insulating material with a gradually increasing thickness, for reasons stated above (cf. FIG. 3).
  • both the inner and the outer periphery of the outer pipe section has a conical shape.
  • the diameter of the inlet of the outer section is selected with respect to the flow rate, pressure or outlet velocity of the flow, and/or other related and desirable parameters.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
  • Details Of Heat-Exchange And Heat-Transfer (AREA)
US10/707,125 2001-05-21 2003-11-21 Arrangement in a pipe joint for a heat exchanger Abandoned US20040104009A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
SE0101797-9 2001-05-21
SE0101797A SE519051C2 (sv) 2001-05-21 2001-05-21 Anordning vid röranslutning för värmeväxlare
PCT/SE2002/000959 WO2002095316A1 (fr) 2001-05-21 2002-05-17 Dispositif de connexion d'un tuyau a un echangeur thermique

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE2002/000959 Continuation WO2002095316A1 (fr) 2001-05-21 2002-05-17 Dispositif de connexion d'un tuyau a un echangeur thermique

Publications (1)

Publication Number Publication Date
US20040104009A1 true US20040104009A1 (en) 2004-06-03

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ID=20284195

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Application Number Title Priority Date Filing Date
US10/707,125 Abandoned US20040104009A1 (en) 2001-05-21 2003-11-21 Arrangement in a pipe joint for a heat exchanger

Country Status (4)

Country Link
US (1) US20040104009A1 (fr)
EP (1) EP1389297A1 (fr)
SE (1) SE519051C2 (fr)
WO (1) WO2002095316A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140024515A1 (en) * 2012-07-23 2014-01-23 Krones Aktiengesellschaft Folding device for article packaging
US9951998B2 (en) 2013-09-30 2018-04-24 Dana Canada Corporation Heat exchanger with integrated co-axial inlet/outlet tube
CN112781405A (zh) * 2021-01-25 2021-05-11 四川空分设备(集团)有限责任公司 一种多通道式高效紧凑型换热器

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2468903A (en) * 1945-09-22 1949-05-03 Tech Studien Ag Vertical tubular heat exchanger
US3090433A (en) * 1959-10-23 1963-05-21 Atomic Power Dev Ass Inc Heat exchanger
US3106957A (en) * 1959-10-15 1963-10-15 Dow Chemical Co Heat exchanger
US3443548A (en) * 1968-01-23 1969-05-13 Vogt & Co Inc Henry High temperature and high pressure steam generator
US3850231A (en) * 1973-05-24 1974-11-26 Combustion Eng Lmfbr intermediate heat exchanger
US3989100A (en) * 1975-05-19 1976-11-02 The Babcock & Wilcox Company Industrial technique
US4216821A (en) * 1977-02-04 1980-08-12 Commissariat A L'energie Atomique Pump/heat exchanger
US4285393A (en) * 1978-10-26 1981-08-25 Ght, Gesellschaft Fur Hochtemperaturreaktor-Technik Mbh Heat exchanger for high-temperature gases
US6119766A (en) * 1996-06-28 2000-09-19 Alfa Laval Ab Plate heat exchanger with connection pipes lined with bellows
US6283199B1 (en) * 1999-05-20 2001-09-04 Toyo Radiator Co., Ltd. Heat exchanger
US20030196781A1 (en) * 2002-04-23 2003-10-23 Wanni Amar S. Heat exchanger with floating head

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2468903A (en) * 1945-09-22 1949-05-03 Tech Studien Ag Vertical tubular heat exchanger
US3106957A (en) * 1959-10-15 1963-10-15 Dow Chemical Co Heat exchanger
US3090433A (en) * 1959-10-23 1963-05-21 Atomic Power Dev Ass Inc Heat exchanger
US3443548A (en) * 1968-01-23 1969-05-13 Vogt & Co Inc Henry High temperature and high pressure steam generator
US3850231A (en) * 1973-05-24 1974-11-26 Combustion Eng Lmfbr intermediate heat exchanger
US3989100A (en) * 1975-05-19 1976-11-02 The Babcock & Wilcox Company Industrial technique
US4216821A (en) * 1977-02-04 1980-08-12 Commissariat A L'energie Atomique Pump/heat exchanger
US4285393A (en) * 1978-10-26 1981-08-25 Ght, Gesellschaft Fur Hochtemperaturreaktor-Technik Mbh Heat exchanger for high-temperature gases
US6119766A (en) * 1996-06-28 2000-09-19 Alfa Laval Ab Plate heat exchanger with connection pipes lined with bellows
US6283199B1 (en) * 1999-05-20 2001-09-04 Toyo Radiator Co., Ltd. Heat exchanger
US20030196781A1 (en) * 2002-04-23 2003-10-23 Wanni Amar S. Heat exchanger with floating head

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140024515A1 (en) * 2012-07-23 2014-01-23 Krones Aktiengesellschaft Folding device for article packaging
US9951998B2 (en) 2013-09-30 2018-04-24 Dana Canada Corporation Heat exchanger with integrated co-axial inlet/outlet tube
CN112781405A (zh) * 2021-01-25 2021-05-11 四川空分设备(集团)有限责任公司 一种多通道式高效紧凑型换热器

Also Published As

Publication number Publication date
SE0101797L (sv) 2002-11-22
WO2002095316A1 (fr) 2002-11-28
EP1389297A1 (fr) 2004-02-18
SE0101797D0 (sv) 2001-05-21
SE519051C2 (sv) 2003-01-07

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Date Code Title Description
AS Assignment

Owner name: REKUPERATOR SVENSKA AB, SWEDEN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:XIE, MAX;REEL/FRAME:014148/0136

Effective date: 20031103

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION