EP1036616A1 - Preparation of metal foam containers - Google Patents

Preparation of metal foam containers Download PDF

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Publication number
EP1036616A1
EP1036616A1 EP00301570A EP00301570A EP1036616A1 EP 1036616 A1 EP1036616 A1 EP 1036616A1 EP 00301570 A EP00301570 A EP 00301570A EP 00301570 A EP00301570 A EP 00301570A EP 1036616 A1 EP1036616 A1 EP 1036616A1
Authority
EP
European Patent Office
Prior art keywords
skin
container
gas
treating
foam material
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.)
Withdrawn
Application number
EP00301570A
Other languages
German (de)
French (fr)
Inventor
Michael Ernest Garrett
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.)
BOC Group Ltd
Original Assignee
BOC Group Ltd
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 BOC Group Ltd filed Critical BOC Group Ltd
Publication of EP1036616A1 publication Critical patent/EP1036616A1/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C1/00—Pressure vessels, e.g. gas cylinder, gas tank, replaceable cartridge
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10—Sintering only
    • B22F3/11—Making porous workpieces or articles
    • B22F3/1103—Making porous workpieces or articles with particular physical characteristics
    • B22F3/1109—Inhomogenous pore distribution
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
    • B22F7/002—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of porous nature
    • B22F7/004—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of porous nature comprising at least one non-porous part
    • B22F7/006—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of porous nature comprising at least one non-porous part the porous part being obtained by foaming
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C1/00—Pressure vessels, e.g. gas cylinder, gas tank, replaceable cartridge
    • F17C1/14—Pressure vessels, e.g. gas cylinder, gas tank, replaceable cartridge constructed of aluminium; constructed of non-magnetic steel
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2201/00—Vessel construction, in particular geometry, arrangement or size
    • F17C2201/01—Shape
    • F17C2201/0147—Shape complex
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2203/00—Vessel construction, in particular walls or details thereof
    • F17C2203/06—Materials for walls or layers thereof; Properties or structures of walls or their materials
    • F17C2203/0602—Wall structures; Special features thereof
    • F17C2203/0612—Wall structures
    • F17C2203/0614—Single wall
    • F17C2203/0617—Single wall with one layer
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2203/00—Vessel construction, in particular walls or details thereof
    • F17C2203/06—Materials for walls or layers thereof; Properties or structures of walls or their materials
    • F17C2203/0634—Materials for walls or layers thereof
    • F17C2203/0636—Metals
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2209/00—Vessel construction, in particular methods of manufacturing
    • F17C2209/21—Shaping processes
    • F17C2209/2109—Moulding
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
    • F17C2223/01—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the phase
    • F17C2223/0107—Single phase
    • F17C2223/0123—Single phase gaseous, e.g. CNG, GNC
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
    • F17C2223/03—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the pressure level
    • F17C2223/036—Very high pressure (>80 bar)
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2260/00—Purposes of gas storage and gas handling
    • F17C2260/01—Improving mechanical properties or manufacturing
    • F17C2260/011—Improving strength
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2260/00—Purposes of gas storage and gas handling
    • F17C2260/01—Improving mechanical properties or manufacturing
    • F17C2260/012—Reducing weight
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2260/00—Purposes of gas storage and gas handling
    • F17C2260/03—Dealing with losses
    • F17C2260/035—Dealing with losses of fluid
    • F17C2260/036—Avoiding leaks
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2270/00—Applications
    • F17C2270/01—Applications for fluid transport or storage
    • F17C2270/0165—Applications for fluid transport or storage on the road
    • F17C2270/0168—Applications for fluid transport or storage on the road by vehicles
    • F17C2270/0178—Cars
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2270/00—Applications
    • F17C2270/01—Applications for fluid transport or storage
    • F17C2270/0186—Applications for fluid transport or storage in the air or in space

Definitions

  • Foam structures are known in industry and the number of applications for metallic foam structures is continually increasing.
  • aluminium foam metal having a continuously connected, open celled (reticulated) geometry is available and employed in :-
  • the high surface to volume ratio allows for a compact design and the high specific stiffness, that is, high strength to weight ratio makes the material useful in aerospace and car applications.
  • Foam structures are now proposed for high pressure gas containers and in particular high pressure gas containers which have an irregular shape.
  • foam material such as metal foams are formed typically by mixing small quantities of a gasifier e.g. titanium nitride with aluminium powder and subjecting the mixture to heat and pressure to form a sintered sheet.
  • the sintered sheet or a portion thereof is then placed in a mould which is then heated to higher temperature at which the metal melts and nitrogen is released from the titanium nitride to provide an even dispersion of bubbles.
  • the moulded object is then allowed to solidify and subsequently shock quenched in a cryogen for example liquid nitrogen.
  • a method of treating the skin of a gas container made from reticulated foam material to render the skin gas impervious comprises treating the surface skin with a liquid sealant and subsequently applying a pressure differential across the skin to draw the liquid sealant so that it flows inwardly from the skin into any open pores, and subsequently allowing the sealant to harden.
  • a vacuum is applied to the interior of the container to create the pressure differential.
  • the gas container is immersed in a vessel containing liquid epoxy resin which is heat settable and heat is applied to set the resin subsequent to the drawing operation.
  • a gas container made from reticulated foam material the skin of the container is treated to render it gas impervious.
  • a vessel 2 is filled with a liquid sealant such as a liquid heat settable epoxy resin 4.
  • a container 6 of an irregular shape made from a metal foam material Immersed in the epoxy resin 4 is a container 6 of an irregular shape made from a metal foam material.
  • the interior of the metal foam material container is in communication with a source of vacuum by means of a tube 8 formed with perforations 9.
  • a pressure differential is applied across the skin 10 of the container 6 by means of a vacuum applied via the tube 8 to the interior of the container 6 for a short period of time so that the liquid epoxy resin 4 flows into any open pore at the skin 10 of the container. Subsequently, the container 6 is heat treated to set the epoxy resin.
  • the skin of the container will thus become impervious to gas flow therethrough.
  • the liquid sealant could be molten metal solder or aluminium oxide.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Materials Engineering (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)

Abstract

A method of treating the skin (10) of a gas container (6) made from reticulated foam material to render the skin gas impervious comprising treating the skin of the container with a liquid sealant (4) and subsequently applying a vacuum to the interior of the container to draw the liquid sealant so that it flows inwardly from the skin into any open pores; and subsequently allowing the liquid sealant to solidify.

Description

  • Foam structures are known in industry and the number of applications for metallic foam structures is continually increasing. For example, aluminium foam metal having a continuously connected, open celled (reticulated) geometry is available and employed in :-
  • a) energy/ impact absorbers;
  • b) heat exchangers; and
  • c) lightweight composite panels.
  • When used with heat exchangers the high surface to volume ratio allows for a compact design and the high specific stiffness, that is, high strength to weight ratio makes the material useful in aerospace and car applications.
  • Foam structures are now proposed for high pressure gas containers and in particular high pressure gas containers which have an irregular shape. When irregular or complex shapes are required then foam material such as metal foams are formed typically by mixing small quantities of a gasifier e.g. titanium nitride with aluminium powder and subjecting the mixture to heat and pressure to form a sintered sheet.
  • The sintered sheet or a portion thereof is then placed in a mould which is then heated to higher temperature at which the metal melts and nitrogen is released from the titanium nitride to provide an even dispersion of bubbles. The moulded object is then allowed to solidify and subsequently shock quenched in a cryogen for example liquid nitrogen.
  • This procedure often leaves the metal foam object with an outer skin in which are formed pores. If the object is to be used as a gas container then said pores will, if not removed or filled, allow the gas to escape from the container.
  • It is an aim of the present invention to provide a method of making a gas container from reticulated foam material which has a skin impervious to gas.
  • According to the present invention, a method of treating the skin of a gas container made from reticulated foam material to render the skin gas impervious comprises treating the surface skin with a liquid sealant and subsequently applying a pressure differential across the skin to draw the liquid sealant so that it flows inwardly from the skin into any open pores, and subsequently allowing the sealant to harden.
  • In one embodiment, a vacuum is applied to the interior of the container to create the pressure differential.
  • Preferably, the gas container is immersed in a vessel containing liquid epoxy resin which is heat settable and heat is applied to set the resin subsequent to the drawing operation.
  • According to a further aspect of the present invention, in a gas container made from reticulated foam material the skin of the container is treated to render it gas impervious.
  • An embodiment of the invention will now be described, by way of example, reference being made to the Figure of the accompanying drawing which is a schematic sketch of apparatus for treating the skin of a gas container made from reticulated foam material.
  • As shown, a vessel 2 is filled with a liquid sealant such as a liquid heat settable epoxy resin 4.
  • Immersed in the epoxy resin 4 is a container 6 of an irregular shape made from a metal foam material. The interior of the metal foam material container is in communication with a source of vacuum by means of a tube 8 formed with perforations 9.
  • In use, a pressure differential is applied across the skin 10 of the container 6 by means of a vacuum applied via the tube 8 to the interior of the container 6 for a short period of time so that the liquid epoxy resin 4 flows into any open pore at the skin 10 of the container. Subsequently, the container 6 is heat treated to set the epoxy resin.
  • The skin of the container will thus become impervious to gas flow therethrough. The liquid sealant could be molten metal solder or aluminium oxide.
  • It will be apparent that the pressure differential across the skin 10 could equally be created by applying a higher pressure to the outside of the container 6 than that existing in the interior of the container.

Claims (7)

  1. A method of treating the skin of a gas container made from reticulated foam material to render the skin gas impervious comprising treating the skin of the container with a liquid sealant and subsequently applying a vacuum to the interior of the container to draw the liquid sealant so that it flows inwardly from the skin into any open pores; and subsequently allowing the liquid sealant to solidify.
  2. A method as claimed in Claim 1, in which a vacuum is applied to the interior of the container to create the pressure differential.
  3. A method as claimed in Claim 1 or Claim 2, in which the container is immersed within a liquid epoxy resin which is contained within a vessel.
  4. A method as claimed in Claim 1, Claim 2 or Claim 3 in which the epoxy resin is heat settable and heat is applied to set the epoxy resin subsequent to the drawing operation.
  5. A gas container made from reticulated foam material in which the container skin is treated to render it gas impervious.
  6. A method of treating the skin of a gas container made from reticulated metal foam material substantially as hereinbefore described.
  7. A gas container made from reticulated metal foam substantially as hereinbefore described.
EP00301570A 1999-03-17 2000-02-28 Preparation of metal foam containers Withdrawn EP1036616A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB9906059.2A GB9906059D0 (en) 1999-03-17 1999-03-17 Improved metal foam containers
GB9906059 1999-03-17

Publications (1)

Publication Number Publication Date
EP1036616A1 true EP1036616A1 (en) 2000-09-20

Family

ID=10849741

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00301570A Withdrawn EP1036616A1 (en) 1999-03-17 2000-02-28 Preparation of metal foam containers

Country Status (2)

Country Link
EP (1) EP1036616A1 (en)
GB (1) GB9906059D0 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992013982A1 (en) * 1991-02-08 1992-08-20 Sandvik Ab Method of manufacturing a compound body
DE19651197A1 (en) * 1995-12-15 1997-06-19 Susan Dietzschold Material for producing porous metal components
DE19704968A1 (en) * 1997-01-28 1998-07-30 Mannesmann Ag Container for storing compressed gas

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992013982A1 (en) * 1991-02-08 1992-08-20 Sandvik Ab Method of manufacturing a compound body
DE19651197A1 (en) * 1995-12-15 1997-06-19 Susan Dietzschold Material for producing porous metal components
DE19704968A1 (en) * 1997-01-28 1998-07-30 Mannesmann Ag Container for storing compressed gas

Also Published As

Publication number Publication date
GB9906059D0 (en) 1999-05-12

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