EP0137815A1 - Gasket for a plate heat exchanger. - Google Patents

Gasket for a plate heat exchanger.

Info

Publication number
EP0137815A1
EP0137815A1 EP19840901022 EP84901022A EP0137815A1 EP 0137815 A1 EP0137815 A1 EP 0137815A1 EP 19840901022 EP19840901022 EP 19840901022 EP 84901022 A EP84901022 A EP 84901022A EP 0137815 A1 EP0137815 A1 EP 0137815A1
Authority
EP
European Patent Office
Prior art keywords
wire
plates
gasket
gasket according
heat exchanger
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.)
Granted
Application number
EP19840901022
Other languages
German (de)
French (fr)
Other versions
EP0137815B1 (en
Inventor
Jons Arthur Dahlgren
Magnus Kallrot
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.)
Alfa Laval Thermal AB
Original Assignee
Alfa Laval Thermal 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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=26658400&utm_source=***_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0137815(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Priority claimed from SE8301081A external-priority patent/SE8301081D0/en
Application filed by Alfa Laval Thermal AB filed Critical Alfa Laval Thermal AB
Priority to AT84901022T priority Critical patent/ATE31975T1/en
Publication of EP0137815A1 publication Critical patent/EP0137815A1/en
Application granted granted Critical
Publication of EP0137815B1 publication Critical patent/EP0137815B1/en
Expired legal-status Critical Current

Links

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
    • F28F3/00—Plate-like or laminated elements; Assemblies of plate-like or laminated elements
    • F28F3/08—Elements constructed for building-up into stacks, e.g. capable of being taken apart for cleaning
    • F28F3/10—Arrangements for sealing the margins

Definitions

  • This invention relates to a gasket for a plate heat exchanger intended to be applied between two adjacent plates forming part of the heat exchanger, the space between the plates forming a passage for a heat exchanging medium.
  • a plate heat exchanger comprises several plates as a rule mounted in a frame and mainly rectangular , which plates are tightened from each other by means of edge gaskets and between which are formed heat transfer areas in the form of parallel-connected heat exchanging passages for through-flow of heat exchanging media, which are conducted to and from the heat exchanger via inlets and outlets arranged at one of its ends, the plates at their corner parts being provided with openings for forming inlet channels and outlet channels for the heat exchanging media.
  • Such plate heat exchangers are manufactured in different sizes with plates the heat transfer areas of which can range from some few square decimeters to several square meters.
  • the plate material is chosen with regard to the field of use but usually comprises stainless or acid-resistant steel.
  • titanium is used, which has excellent resistance against salt water but is very expensive.
  • the edge gaskets sealing between the plates essentially consist of rubber of varying qualities.
  • the sealing pressure of the rubber gaskets is received when the plate package is tightened by the frame by means of set bolts and is maintained by the elasticity of the rubber.
  • a plate heat exchanger can be easily dismantled and inspected or cleaned and thereafter tightened again as long as the gaskets maintain their elasticity and their form.
  • the gaskets At moderate temperatures, below 70-80°C, the gaskets have as long life as 5-8 years. At higher temperatures, more than 100°C, however, the gaskets sink in and lose their original form and by that their sealing capability. Under such circumstances the gaskets have to be exchanged once per year or still more often, which is an expensive procedure.
  • the limitation of the gasket as to temperature and life makes it to the weak link of the plate heat exchanger.
  • the gasket between the plates of the heat exchanger consists of an elastic gasket with a round cross section.
  • the gasket In order to prevent that the gasket is squeezed together too strongly it cooperates with two firm, separate organs, one on each side of the gasket, both of which have a round cross section.
  • the known apparatus is connected with several drawbacks. Firstly, it is unnecessarily complicated and expensive, since it contains three separate elements. Secondly, the apparatus requires a broad gasket groove, i.e. a large, lateral space, which injuriously encroaches upon the heat surface of the heat exchanger plates.
  • the sealing capability of the apparatus will cease if the heat exchanging medium has a high temperature, since the elastic gasket then loses its elasticity.
  • the sealing apparatus consists of elastic elements which are put into a holder of an inelastic material, which follows the outer edges of the heat exchanger plates. Even this apparatus occupies a relatively large, lateral space and limits in that way the heat surface of heat exchanger plates. Further, the apparatus is of such a nature that one type of holder is required for each size of the heat exchanger plate, which means a great cost for this sealing apparatus. Moreover, the elastic strings in the holder are subjected to external influence when using hot heat exchanging media, which means short life for the elastic strings under hard conditions.
  • This invention intends to remove the problems that are connected with known technics. This is made possible by a gasket of the kind mentioned by way of introduction, which is characterized in that it comprises a wire of hard and essentially inelastic material, which essentially bridges the distance between the two plates and that the wire at least at certain places along its extension is connected with the plates in such a way that the heat exchanging medium cannot pass the wire.
  • heat exchanger plates 1 provided with grooves 2 into which a sealing element 3 is applied.
  • the sealing element 3 is intended to constitute a seal between two adjacent plates 1 for a medium streaming in the channel 4 between these plates 1.
  • the sealing elements 3 comprises a round wire which is preferably made of the same metallic material as the plates and functions as a bridging component between the plates 1.
  • the metal wire 3 When applying the metal wire 3 this one is put into the gasket groove 2 and is formed in accordance with the form of the groove in the plates.
  • the round metal profile allows itself to be easily bent without having its cross section deformed.
  • the metal wire 3 is joined to final form preferably by butt welding, whereafter the weld joint is ground.
  • the material metal is mentioned but another hard and resistant material can be used.
  • the wire profile can have another form than round.
  • a thin-walled metal tube is preferably used, which one can be somewhat more flexible than a solid metal wire.
  • the bridging metal wire 3 shall have a diameter that mainly corresponds to the distance between two adjacent plates 1.
  • the wires in the different channels in a plate package support each other in great parts of the gasket grooves but not at the ports , where every second gasket is taken away so that a liquid can stream into the channels.
  • the sealing pressure metal wire-plate surface is low in certain parts of the sealing length, and, therefore, the metal wire cannot independently manage the sealing against the plates. Therefore, the sealing function of the metal wire ought to be improved at least in these places.
  • This sealing function can be arranged in several ways :
  • the coating with the soft material according to A) and B) is preferably made in such a way that when applying the wire between the plates the wire is attached to the plates.
  • connection coating is denoted by the figure 5 and the joint connections in the form of glued joint, soldered seam or weld joint by the figure 6.
  • the metal wire is connected with the plates along all its length.
  • connection is preferably made in the following way:
  • the metal wire is put into the gasket groove of the plate, whereafter the plate with wire is covered by a soldering sheet. On the top of this is put a new plate with wire and a soldering sheet and so on. When heating in a suitable way the soldering sheet melts and through influence of the capillary force the solder flows into the rooms between the metal wire and the plates.
  • the metal wires need not lie in the same plane and support each other but can also lie displaced in relation to each other in the gasket grooves, the material of the plate being able to yield and take up movements, when the wires expand during heating.
  • the sealing apparatus is very simple and cheap both to produce and apply. Secondly, the sealing apparatus only requires a narrow gasket groove, whereby only an exceedingly small encroaching upon the heat surface of the heat exchanger plates is made. Thirdly, the sealing apparatus in contrast to conventional rubber gaskets is very suitable to use in heat exchangers for hot and aggressive media. The reason why is that the main component of the gasket comprises a wire that bridges the distance between the plates, which wire is preferably made of metal and at least at certain places cooperates with a connection material.

Landscapes

  • 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)

Abstract

Joint d'étanchéité pour un échangeur thermique à plaque, destiné à être appliqué entre deux plaques adjacentes faisant partie de l'échangeur thermique, l'espace compris entre les deux plaques formant un passage pour un fluide d'échange thermique. L'invention se caractérise par le fait que le joint d'étanchéité comprend un câble (3) en un matériau dur et essentiellement inélastique, qui s'étend sensiblement entre les deux plaques (1), et que ce câble (3) au moins en quelques points sur sa longueur est relié aux plaques (1) de sorte que le fluide d'échange thermique ne peut traverser le câble (3).Gasket for a plate heat exchanger, intended to be applied between two adjacent plates forming part of the heat exchanger, the space between the two plates forming a passage for a heat exchange fluid. The invention is characterized in that the seal comprises a cable (3) made of a hard and essentially inelastic material, which extends substantially between the two plates (1), and that this cable (3) at least at a few points along its length is connected to the plates (1) so that the heat exchange fluid cannot pass through the cable (3).

Description

Gasket for a plate heat exchanger
This invention relates to a gasket for a plate heat exchanger intended to be applied between two adjacent plates forming part of the heat exchanger, the space between the plates forming a passage for a heat exchanging medium.
A plate heat exchanger comprises several plates as a rule mounted in a frame and mainly rectangular , which plates are tightened from each other by means of edge gaskets and between which are formed heat transfer areas in the form of parallel-connected heat exchanging passages for through-flow of heat exchanging media, which are conducted to and from the heat exchanger via inlets and outlets arranged at one of its ends, the plates at their corner parts being provided with openings for forming inlet channels and outlet channels for the heat exchanging media.
Such plate heat exchangers are manufactured in different sizes with plates the heat transfer areas of which can range from some few square decimeters to several square meters. The plate material is chosen with regard to the field of use but usually comprises stainless or acid-resistant steel. For certain purposes titanium is used, which has excellent resistance against salt water but is very expensive.
The edge gaskets sealing between the plates essentially consist of rubber of varying qualities. The sealing pressure of the rubber gaskets is received when the plate package is tightened by the frame by means of set bolts and is maintained by the elasticity of the rubber.
A plate heat exchanger can be easily dismantled and inspected or cleaned and thereafter tightened again as long as the gaskets maintain their elasticity and their form. At moderate temperatures, below 70-80°C, the gaskets have as long life as 5-8 years. At higher temperatures, more than 100°C, however, the gaskets sink in and lose their original form and by that their sealing capability. Under such circumstances the gaskets have to be exchanged once per year or still more often, which is an expensive procedure. The limitation of the gasket as to temperature and life makes it to the weak link of the plate heat exchanger.
According to a known solution shown in the German patent publication 1.149.027 the gasket between the plates of the heat exchanger consists of an elastic gasket with a round cross section. In order to prevent that the gasket is squeezed together too strongly it cooperates with two firm, separate organs, one on each side of the gasket, both of which have a round cross section.
The known apparatus is connected with several drawbacks. Firstly, it is unnecessarily complicated and expensive, since it contains three separate elements. Secondly, the apparatus requires a broad gasket groove, i.e. a large, lateral space, which injuriously encroaches upon the heat surface of the heat exchanger plates.
Thirdly, the sealing capability of the apparatus will cease if the heat exchanging medium has a high temperature, since the elastic gasket then loses its elasticity.
According to another known solution (DE-AS 1.207.947) the sealing apparatus consists of elastic elements which are put into a holder of an inelastic material, which follows the outer edges of the heat exchanger plates. Even this apparatus occupies a relatively large, lateral space and limits in that way the heat surface of heat exchanger plates. Further, the apparatus is of such a nature that one type of holder is required for each size of the heat exchanger plate, which means a great cost for this sealing apparatus. Moreover, the elastic strings in the holder are subjected to external influence when using hot heat exchanging media, which means short life for the elastic strings under hard conditions.
This invention intends to remove the problems that are connected with known technics. This is made possible by a gasket of the kind mentioned by way of introduction, which is characterized in that it comprises a wire of hard and essentially inelastic material, which essentially bridges the distance between the two plates and that the wire at least at certain places along its extension is connected with the plates in such a way that the heat exchanging medium cannot pass the wire.
The invention shall hereafter be described more closely in connection with the accompanying drawing which as examples shows some embodiments of the invention.
In the drawing there are shown heat exchanger plates 1 provided with grooves 2 into which a sealing element 3 is applied. The sealing element 3 is intended to constitute a seal between two adjacent plates 1 for a medium streaming in the channel 4 between these plates 1.
The sealing elements 3 comprises a round wire which is preferably made of the same metallic material as the plates and functions as a bridging component between the plates 1.
When applying the metal wire 3 this one is put into the gasket groove 2 and is formed in accordance with the form of the groove in the plates. The round metal profile allows itself to be easily bent without having its cross section deformed. The metal wire 3 is joined to final form preferably by butt welding, whereafter the weld joint is ground.
The material metal is mentioned but another hard and resistant material can be used. Likewise, the wire profile can have another form than round.
A thin-walled metal tube is preferably used, which one can be somewhat more flexible than a solid metal wire.
The bridging metal wire 3 shall have a diameter that mainly corresponds to the distance between two adjacent plates 1.
The wires in the different channels in a plate package support each other in great parts of the gasket grooves but not at the ports , where every second gasket is taken away so that a liquid can stream into the channels.
Thus , the sealing pressure metal wire-plate surface is low in certain parts of the sealing length, and, therefore, the metal wire cannot independently manage the sealing against the plates. Therefore, the sealing function of the metal wire ought to be improved at least in these places.
This sealing function can be arranged in several ways :
A) Connection of the wire with the plates by means of a soft material, for instance rubber, teflon and/or plastics material, the wire being coated with the soft material;
B) Connection of the wire with the plates by means of a soft material, for instance rubber, teflon and/or plastics material, the sealing surfaces of the plates being coated with the soft material;
The coating with the soft material according to A) and B) is preferably made in such a way that when applying the wire between the plates the wire is attached to the plates.
C) Connection of the wire with the plates by means of I) a temperature- and liquid resistant glue;
II) soldering;
III) welding.
The different ways A-C are shown in the drawing, where the connection coating is denoted by the figure 5 and the joint connections in the form of glued joint, soldered seam or weld joint by the figure 6.
In certain applications the metal wire is connected with the plates along all its length.
In those cases when the whole metal wire is connected with the plates by means of soldering the connection is preferably made in the following way:
The metal wire is put into the gasket groove of the plate, whereafter the plate with wire is covered by a soldering sheet. On the top of this is put a new plate with wire and a soldering sheet and so on. When heating in a suitable way the soldering sheet melts and through influence of the capillary force the solder flows into the rooms between the metal wire and the plates.
The metal wires need not lie in the same plane and support each other but can also lie displaced in relation to each other in the gasket grooves, the material of the plate being able to yield and take up movements, when the wires expand during heating.
There are several advantages connected with this described sealing apparatus. Firstly, the sealing apparatus is very simple and cheap both to produce and apply. Secondly, the sealing apparatus only requires a narrow gasket groove, whereby only an exceedingly small encroaching upon the heat surface of the heat exchanger plates is made. Thirdly, the sealing apparatus in contrast to conventional rubber gaskets is very suitable to use in heat exchangers for hot and aggressive media. The reason why is that the main component of the gasket comprises a wire that bridges the distance between the plates, which wire is preferably made of metal and at least at certain places cooperates with a connection material.

Claims

Claims
1. Gasket for a plate heat exchanger intended to be applied between two adjacent plates forming part of the heat exchanger, the space between the plates forming a passage for a heat exchanging medium, c h a r a c t e r i z e d i n that it comprises a wire (3) of hard and essentially inelastic material, which essentially bridges the distance between the two plates (1) , and that the wire (3) at least in certain places along its extension is connected with the plates (1) in such a way that the heat exchanging medium cannot pass the wire (3).
2. Gasket according to claim 1, c h a r a c t e r i z e d i n that the wire (3) is flexible and put into a groove (2) of one of the plates (1) , the wire being formed in accordance with the form of the groove (2).
3. Gasket according to claim 1 or 2, c h a r a c t e r i z e d i n that the wire (3) comprises a thin-walled metal tube.
4. Gasket according to anyone of the preceding claims, c h a r a c t e r i z e d i n that the cross-section of the wire (3) has the form of a circle.
5. Gasket according to anyone of the preceding claims, c h a r a c t e r i z e d i n that the wire (3) is connected with the plates (1) by means of a soft material (5) like rubber, teflon and/or plastics material, the wire (3) being coated with the soft material (5).
6. Gasket according to anyone of the claims 1-4, c h a r a c t e r i z e d i n that the wire (3) is connected with the plates (1) by means of a soft material (5) like rubber, teflon and/or plastics material, the sealing surfaces of the plates (1) being coated with the soft material (5).
7. Gasket according to anyone of the claims 1-4, c h a r a c t e r i z e d i n that the wire (3) is connected with the plates (1) by means of glue.
8. Gasket according to anyone of the claims 1-4, the wire (3) comprising a metallic material, c h a r a c t e r i z ed i n that the wire (3) is connected with the plates (1) by means of solder.
9. Gasket according to anyone of the claims 1-4, the wire (3) comprising a metallic material, c h ar a c t e r i z e d i n that the wire (3) Is connected with the plates (1) by means of a weld joint.
10. Gasket according to claim 8 or 9, c h a r a c t e r i z e d i n that the wire (3) is connected with the plates (1) along all Its length.
EP19840901022 1983-02-28 1984-02-22 Gasket for a plate heat exchanger Expired EP0137815B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT84901022T ATE31975T1 (en) 1983-02-28 1984-02-22 GASKET FOR A PLATE HEAT EXCHANGER.

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
SE8301081A SE8301081D0 (en) 1983-02-28 1983-02-28 SEAL FOR PLATE HEAT EXCHANGER
SE8301081 1983-02-28
SE8302787 1983-05-18
SE8302787A SE8302787L (en) 1983-02-28 1983-05-18 SEAL FOR PLATE HEAT EXCHANGER

Publications (2)

Publication Number Publication Date
EP0137815A1 true EP0137815A1 (en) 1985-04-24
EP0137815B1 EP0137815B1 (en) 1988-01-13

Family

ID=26658400

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19840901022 Expired EP0137815B1 (en) 1983-02-28 1984-02-22 Gasket for a plate heat exchanger

Country Status (7)

Country Link
EP (1) EP0137815B1 (en)
BR (1) BR8406165A (en)
DE (1) DE3468733D1 (en)
DK (1) DK511584D0 (en)
FI (1) FI844197A0 (en)
SE (1) SE8302787L (en)
WO (1) WO1984003354A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3544587A1 (en) * 1985-12-17 1987-06-25 Bruss Dichtungstechnik Elastomer seal for heat exchangers

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7306027B2 (en) * 2004-07-01 2007-12-11 Aavid Thermalloy, Llc Fluid-containing cooling plate for an electronic component

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3111325A (en) * 1960-04-14 1963-11-19 Duriron Co Fabrication of sinterable plastic omicron-ring seal
DE1149027B (en) * 1961-03-14 1963-05-22 Basf Ag Sealing arrangement for plate heat exchangers, consisting of softer seals that are between harder seals
DE1207947B (en) * 1962-08-01 1965-12-30 Separator Ab Device for sealing between the plates of a plate heat exchanger
SE424906B (en) * 1976-10-14 1982-08-16 Hisaka Works Ltd PACKAGING FOR PLASTIC EXCHANGERS
GB2033497A (en) * 1978-09-14 1980-05-21 Central Electr Generat Board Seals

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8403354A1 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3544587A1 (en) * 1985-12-17 1987-06-25 Bruss Dichtungstechnik Elastomer seal for heat exchangers

Also Published As

Publication number Publication date
EP0137815B1 (en) 1988-01-13
DK511584A (en) 1984-10-26
SE8302787L (en) 1984-08-29
DE3468733D1 (en) 1988-02-18
WO1984003354A1 (en) 1984-08-30
FI844197L (en) 1984-10-25
DK511584D0 (en) 1984-10-26
BR8406165A (en) 1985-03-12
SE8302787D0 (en) 1983-05-18
FI844197A0 (en) 1984-10-25

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