US3698589A - Cryogenic storage apparatus - Google Patents
Cryogenic storage apparatus Download PDFInfo
- Publication number
- US3698589A US3698589A US888151A US3698589DA US3698589A US 3698589 A US3698589 A US 3698589A US 888151 A US888151 A US 888151A US 3698589D A US3698589D A US 3698589DA US 3698589 A US3698589 A US 3698589A
- Authority
- US
- United States
- Prior art keywords
- neck tube
- inner vessel
- outer shell
- vessel
- thermoset
- 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
Links
Images
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
- F17C3/00—Vessels not under pressure
- F17C3/02—Vessels not under pressure with provision for thermal insulation
- F17C3/08—Vessels not under pressure with provision for thermal insulation by vacuum spaces, e.g. Dewar flask
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47J—KITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
- A47J41/00—Thermally-insulated vessels, e.g. flasks, jugs, jars
- A47J41/02—Vacuum-jacket vessels, e.g. vacuum bottles
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47J—KITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
- A47J41/00—Thermally-insulated vessels, e.g. flasks, jugs, jars
- A47J41/02—Vacuum-jacket vessels, e.g. vacuum bottles
- A47J41/022—Constructional details of the elements forming vacuum space
- A47J41/028—Constructional details of the elements forming vacuum space made of metal
-
- 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
- F17C2201/0104—Shape cylindrical
- F17C2201/0109—Shape cylindrical with exteriorly curved end-piece
-
- 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
- F17C2201/03—Orientation
- F17C2201/032—Orientation with substantially vertical main axis
-
- 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
- F17C2203/01—Reinforcing or suspension means
- F17C2203/014—Suspension means
- F17C2203/018—Suspension means by attachment at the neck
-
- 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
- F17C2203/03—Thermal insulations
- F17C2203/0304—Thermal insulations by solid means
- F17C2203/0308—Radiation shield
- F17C2203/032—Multi-sheet layers
-
- 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
- F17C2203/03—Thermal insulations
- F17C2203/0304—Thermal insulations by solid means
- F17C2203/0345—Fibres
-
- 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
- F17C2203/03—Thermal insulations
- F17C2203/0391—Thermal insulations by vacuum
-
- 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
- F17C2203/0626—Multiple walls
- F17C2203/0629—Two walls
-
- 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
- F17C2203/0639—Steels
- F17C2203/0643—Stainless steels
-
- 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
- F17C2203/0658—Synthetics
- F17C2203/0663—Synthetics in form of fibers or filaments
- F17C2203/0673—Polymers
-
- 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
- F17C2205/00—Vessel construction, in particular mounting arrangements, attachments or identifications means
- F17C2205/01—Mounting arrangements
- F17C2205/0153—Details of mounting arrangements
- F17C2205/018—Supporting feet
-
- 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
- F17C2260/03—Dealing with losses
- F17C2260/031—Dealing with losses due to heat transfer
- F17C2260/033—Dealing with losses due to heat transfer by enhancing insulation
Definitions
- typical containers for storing cryogenic liquids such as liquid oxygen and liquid nitrogen in relatively small quantities of about 15-25 liters comprised an inner storage vessel, an outerprotective shell which enclosed the inner vessel thereby forming an evacuable insulation therebetween,,and a relatively long narrow neck tube whichserved as the entrance to the .inner vessel.
- the inner-vessel was usually supported entirely by suspension from the-top of the outer shell by such neck tube.
- the .prior art found it necessaryto employ a neck tube constructed of a material such as stainlesssteel. These strength and heat leak requirements are conflicting in that a relatively strong material such as stainless-steel is also a relatively high conductor of heat.'Furthermore,
- FIGURE is a view of a longitudinal,cross-section of a low-boiling liquefied gas container embodying principles of the present invention.
- This invention is embodied in an improved vacuuminsulated, low temperature storage container having an.
- the neck tube of the container is constructed of a impervious reinforced fibrous laminate impregnated with a therrnosetting synthetic resin.
- the gas permeation rate of the neck tube material must be less than 1 X 10' cu. cm./sec. of helium at a pressure of one atm. as determined by testing a tube havinga 1% inch inside diameter, a 1/16 inch wall thickness and a length of 2 inches in a Model MS-9A Veeco Mass Spectrometer Leak Detector.
- substantially gas impervious as employed herein means those materials having a gas permeation rate of from zeroto 1 X l0 cu. cm./sec. of'helium.
- the permeation rate is zero.
- the laminates employed as the neck tube can be of any material or synthetic fiber in random or orderly manner, such as is found in paper, cloth, or the like or any reinforcing or rigidifying fiber such as cellulosic fibers, glass fibers,
- the degree Ofimpregnation of the reinforced laminate should be sufficient to produce, after curing of the resin to a thersates, and epoxy resins such as the polyglycidyl ethers of polyhydric phenols, serve excellently as the thermose tting resins of these laminates although other thermosetting resins such as polyester resins providing the same or equivalent degree of gas imperviousness can be employed.
- these resins can be applied to liquid resins or solvent solutions of solid resins to impregnate a preformed neck tube and the resin cured in situ by heating to elevated temperatures or by curing aidsor hardeners such as polyfunctional amines, or both to a therrnoset condition.
- the neck tube can be fabricated from preimpregnated and cured reinforced laminates in tubular form, or they can be prepared from partially cured resin-impregnated paper or cloth webs, and finally cured to a thermoset condition after forming.
- gas impervious neck tubes constructed of thermoset resin impregnated fibrous laminates, in a manner to be described, effectively reduce vaporization losses of the liquefied gas due to atmospheric heatleakage into the inner vessel as well as maintain the insulation qualities of the evacuable-insulation space surrounding the inner vessel by preventing loss of the vacuum therethrough.
- a gas impervious neck tube is preferably constructed of resin impregnated fibrous laminates having the following physical properties:
- thermoset resin impregnated laminates reduce liquified gas vaporization induced by heat leakage to less than about 70 percent of the loss attained by employing a stainless steel neck tube.
- the preferred embodiment of this invention employs opacified insulation wherein such insulation substantially completely fills the evacuable insulation space between the outer shell and the inner vessel.
- lower quality insulating systems such as the powder-invacuum insulators or straight vacuum with highly polished outer shell inner and inner vessel outer surfaces may be alternately employed.
- opacified insulation refers to a two-component insulating system comprising a low heat conductive, radiation permeable material and a radiant heat impervious material which is capable of reducing the passage of infrared rays without significantly increasing the thermal conductivity of the insulating system.
- opacified insulation is more fully described in U.S. Pat. No. 2,967,152 issued Jan. 3, I96], and copending U.S. application Ser. No. 597,947, filed July 16, 1956, now U.S. Pat. No. 3,007,596 both in the name of L. C. Matsch.
- the opacified insulation of the former incorporates the radiation impervious barrier directly into the low heat conductive material.
- the radiation impervious barrier directly into the low heat conductive material.
- equal parts by weight of copper flakes and finely divided silica might be mixed.
- the latter material has a very low solid conductivity value but is quite transparent toradiation.
- the copper flakes serve to markedly reduce the radiant heat inleak.
- the latter referenced opacified insulation takes the form of low heat conductive material separated by a multiplicity of radiation-impervious barriers.
- the low heat conductive material may be a fiber insulation produced in sheet form. Examples include a filamentamicrons. Also, such fibrous materials preferably have a fiber orientation substantially perpendicular to the direction of heat flow across the insulation space.
- the spaced radiation-impervious barriers may comprise either a metal, metal oxide, or metal coated material, such as aluminum coated plastic film, or other radiation reflective or radiation adsorptive material or a suitable combination thereof.
- Radiation reflective material, comprising thin metal foils are, particularly suited in the practice of the present invention, for example, reflective sheets of aluminum foil having a thickness between 0.2 millimeters and 0.002 millimeters.
- fiber sheets When fiber sheets are used as the low conductive material, they may additionally serve as a support means for the relatively fragile radiant heat impervious sheets.
- an aluminum foil-fiber insulation be spirally wrapped around the inner vessel with one end of the insulation wrapping in contact with the inner vessel, and the other end nearest the outer shell, or in actual contact therewith.
- a gas-removing material such as an adsorbent may be used in the insulation space to remove by adsorption any gas entering through the joints of the 'outer shell.
- crystalline zeolitic molecular sieves having pores of at least about 5 Angstrom units in size, as disclosed and claimed in U.S. Pat. No. 2,900,800 issued in the name of P. E. Loveday, are preferred as the adsorbent. They have extremely high adsorptive capacity at the temperature and pressure conditions existing in the insulation space and are chemically inert toward any gases which might leak into the insulation space.
- neck tube 10 is constructed of a paper or fabric tube impregnated with a thermoset ry glass material such as glass wool and fiber glass,
- Neck tube 10 is preferably joined to the outer shell 12 of container 14 and to the inner storage vessel 16 by means of rigid annular. support rings 18 and 20 respectively. As shown, neck tube 10 is preferably positioned by annular grooves 17 and 19 in rings 18 and 20, and bonded therein. Rings 18 and 20 are employed to simplify joining the neck tube to the inner vessel and the outer shell inasmuch as it has been found that stronger joints may be constructed by bonding the neck tube in grooves. In this manner, the shear strength of the bonding resin is more fully utilized and a more leak tight joint is achieved. If a relatively weaker joint can be tolerated, the neck tube joints can be formed without the use of grooves. It has been found that A-l2" epoxy resin manufactured by Armstrong Products Co. of Warsaw, Ind., is a suitable bonding agent.
- Inner vessel 16 is preferably supported in tension by neck tube 10 at one end, the tensile strength of said tube being sufficient to support the entire weight of said vessel and its contents.
- Insulation space 24 between outer shell 12 and inner vessel 16 is preferably substantially completely filled with an opacified insulation material. Such insulating material affords lateral support for inner vessel 16 but no appreciable vertical support.
- Insulation space 24 is preferably evacuated to a low positive pressure of less than about microns of mercury and preferably less than about 0.5 microns by a vacuum pump capable of being connected to pinch-off tube 25.
- Absorbent material 26 such as silica gel or sodium zeolite A is located within enclosure 28 attached to the bottom of inner vessel 16 to assist in preserving the low vacuum pressure within insulation space 24.
- neck tube 10 The access opening formed by neck tube 10 is substantially occupied by an annular low heat conductive plug such that liquid vaporized by unavoidable heat leakage will flow out through the annular space between plug 30 and neck tube 10. The vaporizedgas will absorb a substantial part of the heat which would otherwise be conducted into inner vessel 16 by neck tube 10.
- Low heat conductive plug 30 may be constructed of a material such as foam plastic or cork.
- a neck tube constructed of a reinforced thermoset phenol-aldehyde or epoxy resin laminate will not creep or change its shape under varying the temperature conditions.
- support rings 18 and 20 and neck tube 10 are designed to bearthe vertical loads that are imposed upon the inner vessel and, since rigidity and dimensional stability are important, the properties exhibited, and mentioned above, by these reinforced thermoset resin laminates are desirable.
- the bonded joints, between neck tube 10 and annular rings 18 and 20 are preferably formed by curing an application of epoxy resin, such as the previously noted A-l2 brand resin, at temperature of about 150F.
- epoxy resin such as the previously noted A-l2 brand resin
- outer shell 12 and inner vessel 16 should be connected, by means such as welding to annular rings 18 and 20 prior to their assembly with neck tube 10 so that theheat necessary to form the weld joining rings 18 and 20 to outer shell 12 and inner vessel 16 will not damage the bonded joints in the annular grooves of rings 18 and 20. Therefore, to assemble this arrangement, inner vessel 16 with its welded ring 20 is first attached to the support member 22 within the lower section of outer shell 12.
- Neck tube 10 is then placed in the annular groove of ring 20 and an upper section of outer shell 12, with annular ring 18 attached, is placed into position, elastically elongated and preferably girth welded at 11 to its first lower segment.
- the resulting joints in the annular grooves 17 and 19 of rings 18 and 20 are then cured, employing the epoxy resin as the neck tube joint bonding agent.
- Insulation space 24 is preferably evacuated similtaneously with the curing process.
- the ends of the neck tube and the annular grooves should be sandblasted prior to bonding to provide sufficiently roughened surfaces for proper bonding thereof.
- the sandblasting may be accomplished by projecting l20-mesh aluminum oxide particles against the surfaces of the grooves at a velocity of about 500 fps.
- a low temperature storage container having an outer shell and an inner storage vessel each with an upper opening wherein the two openings are vertically aligned and with said inner storage vessel and outer she I sized to enclose an intervening vacuum insulation space
- the improvement comprising a cylindrical neck tube with opposite ends respectively gas-tightly sealed to the edges of said upper openings in the outer shell and inner vessel so as to provide a relatively wide access hole from the atmosphere to the interior of said inner vessel, said neck tube being formed of a substantially gas impervious material with the outer wall- Compressive strength-at least 10,000 PSI Tensile strength-at least 8,500 PSI Specific heat-between 0.26-0.40
- a storage container according to claim 1 in which the neck tube is formed of material having a specific gravity of at least 1.10.
- a low temperature vacuum insulated storage container having an outer shell and an inner storage vessel each with an upper opening wherein the two openings are vertically aligned
- the improvement comprising a cylindrical neck tube with opposite ends respectively gas-tightly sealed to the edges of said upper openings in the outer shell and inner vessel so as to provide a relatively wide access hole from the atmosphere to the interior of said inner vessel, said neck tube being formed of a substantially gas impervious material selected from the group consisting of paper reinforced with a thermoset phenol-formaldehyde resin, glass fiber reinforced with a thermoset epoxy resin, and glass fiber reinforced with a thermoset polyester resin, said neck tube being loaded in tension by said inner vessel as the sole suspension means therefor and wherein support rings with grooves that face each other axially of the container are connected to the edges of said upper openings in the outer shell and inner vessel, and the opposite ends of said neck tube are positioned and gas-tightly sealed in said grooves.
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Food Science & Technology (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Filling Or Discharging Of Gas Storage Vessels (AREA)
Abstract
A double walled container having an inner vessel and an outer shell with an intervening vacuum insulation space, including a neck tube formed of certain gas impervious fiber reinforced plastic compositions having certain physical properties, the neck tube providing access to the inner vessel and also being loaded in tension by the inner vessel as the sole suspension means therefor.
Description
Haumann et al. ...........220/15 Skinner et a1................220/15 Trentham et a1. ...........220/l5 by Simonds, Weith &
ABSTRACT OTHER PUBLICATIONS Handbook of Plastics Bigelow, Second Edition, Jan. 1949, Published by D. Van Nostrand, 1nc., Reprint of Nov. 1955, Page 55.
Primary Examiner-Joseph R. Leclair Assistant Examiner-James R. Garrett Attorney-Paul A. Rose, John C. LeFever and Harrie M. Humphreys 220/9 LG ,A'. double walled container having an inner vessel and an outer shell with an intervening vacuum insulation space, including a neck tube formed of certain gas impervious fiber reinforced plastic compositions having certain physical properties, the neck tube providing access to the inner vessel and also being loaded in tension by the inner vessel as the sole suspension means therefor. I
5 Claims, 1 Drawing Figure M m a w A U A, v a m m H M i 0 t M 0/ United States Patent Perry CRYOGENIC STORAGE APPARATUS James L. Perry, Totowa Buro, N.J.
Inventor:
Union Carbide Corporation [73] Assignee:
1 8 D n o 9 w m. 1 M 9 2 moo U 8 D8v -t m R .mL P mp. FA NH 22 ll Continuation of Ser. No. 599,343, Dec.
1966, abandoned, which is, a continuation of Ser. No. 337,696, Dec. 26, 1963, abandoned,
which is a continuation-in-part of Ser. No. 149,356, Nov. 1, 1961, abandoned.
[52] US. [51] Int. Cl.
mam N 2 l mum 6 m mflw n mdn In oa vi m m u ama CCH 902 566 999 111 //l 275 C RYOGENIC STORAGE APPARATUS This application is a continuation of Ser. No. 599,343, filed Dec. 1, 1966, now abandoned, which latter application is a continuation of Ser. No. 337,696, filed Dec. 26, 1963, now abandoned, said last mentioned application being a continuation-impart of Ser. No. 149,356 filed Nov. 1, 1961, now abandoned- This invention relates to cryogenic storage apparatus andmore particularlyto adouble-walled, vacuum insulated cryogenic storage container.
Heretofore, typical containers for storing cryogenic liquids such as liquid oxygen and liquid nitrogen in relatively small quantities of about 15-25 liters comprised an inner storage vessel, an outerprotective shell which enclosed the inner vessel thereby forming an evacuable insulation therebetween,,and a relatively long narrow neck tube whichserved as the entrance to the .inner vessel. The inner-vessel ,was usually supported entirely by suspension from the-top of the outer shell by such neck tube. These containers were extremely fragile in that the inner vessel often ruptured at the necktubeinner vessel joint due to impact andacceleration forces experienced during-handling. I
Another disadvantage of these containers was the relatively small diameter of the neck tube which hampered access to the inner vessel. Enlargement of the neck tube opening of these containers was no solution, however, since thisincreased the heat leakage into the inner vessel. Not only was a portion of an otherwise well-insulated area replaced by a larger uninsulated opening, but the-heat leakage along the walls of th neck tube itself was significantlyincreased.
In order to preserve the liquefied gas with a minimum of evaporation due to excessive heat leakage and yet provide a relatively sturdy container, the .prior art found it necessaryto employ a neck tube constructed of a material such as stainlesssteel. These strength and heat leak requirements are conflicting in that a relatively strong material such as stainless-steel is also a relatively high conductor of heat.'Furthermore,
the prior art found it necessary toiemployfaneck tube constructed of such material toensure an effective seal of the evacuated insulation space surrounding the inner product liquid vessel. The gas imperviousness and high strength advantage of stainless steelwas only obtained at the cost of gas loss due to the contribution to heat leakage into the inner vessel.
It is an object of this invention to provide a low-temperature storage container employing an improved neck tube constructed of highstrength material .which has the advantages of large access opening,-strength, and vacuum tightness while substantially'reducing the heat leakage into theinner vessel.,An other object is to provide a low temperature liquefied gas storage container with an improved neck tube that is constructed of a gas impervious and low-heat conductive material. These and other objects of .the invention .will become apparent from the following discussion and the accompanying drawing in which:
FIGURE is a view of a longitudinal,cross-section of a low-boiling liquefied gas container embodying principles of the present invention.
While theinvention will be described in conjunction with a low-boiling liquefied gas storage container, it is to be understood that it is equally well-suited for utilization in other type low-temperature storage consubstantially gas tainers such as those used for the preservation of materials such as biological substances where a lowboiling liquefied gas is employed as a refrigerantto surroundsuch biological materials.
This invention is embodied in an improved vacuuminsulated, low temperature storage container having an.
'outer protective shell, an innerv product vessel, an
evacuable insulationspace therebetween, and a neck tube connecting the outer shell to the inner vessel large enough to provide access to the interior storage space of such inner vessel.
The neck tube of the container is constructed of a impervious reinforced fibrous laminate impregnated with a therrnosetting synthetic resin. The gas permeation rate of the neck tube material must be less than 1 X 10' cu. cm./sec. of helium at a pressure of one atm. as determined by testing a tube havinga 1% inch inside diameter, a 1/16 inch wall thickness and a length of 2 inches in a Model MS-9A Veeco Mass Spectrometer Leak Detector. Hence the term substantially gas impervious as employed herein means those materials having a gas permeation rate of from zeroto 1 X l0 cu. cm./sec. of'helium. Preferably the permeation rate is zero. The laminates employed as the neck tube can be of any material or synthetic fiber in random or orderly manner, such as is found in paper, cloth, or the like or any reinforcing or rigidifying fiber such as cellulosic fibers, glass fibers,
synthetic fibers or the like, and thoroughly impregnated with a cured therrnosetting resin. The degree Ofimpregnation of the reinforced laminate should be sufficient to produce, after curing of the resin to a thersates, and epoxy resins such as the polyglycidyl ethers of polyhydric phenols, serve excellently as the thermose tting resins of these laminates although other thermosetting resins such as polyester resins providing the same or equivalent degree of gas imperviousness can be employed. These resins can be applied to liquid resins or solvent solutions of solid resins to impregnate a preformed neck tube and the resin cured in situ by heating to elevated temperatures or by curing aidsor hardeners such as polyfunctional amines, or both to a therrnoset condition. If desired the neck tube can be fabricated from preimpregnated and cured reinforced laminates in tubular form, or they can be prepared from partially cured resin-impregnated paper or cloth webs, and finally cured to a thermoset condition after forming. It has been found that gas impervious neck tubes constructed of thermoset resin impregnated fibrous laminates, in a manner to be described, effectively reduce vaporization losses of the liquefied gas due to atmospheric heatleakage into the inner vessel as well as maintain the insulation qualities of the evacuable-insulation space surrounding the inner vessel by preventing loss of the vacuum therethrough.
To achieve these results, a gas impervious neck tube is preferably constructed of resin impregnated fibrous laminates having the following physical properties:
. Specific Gravity Compressive Strength Tensile Strength Specific Heat Thermal Conductivity cal/sec/cmldeg Cl cm.
These thermoset resin impregnated laminates reduce liquified gas vaporization induced by heat leakage to less than about 70 percent of the loss attained by employing a stainless steel neck tube. For example a material known commercially as Synthane Grade X manufactured by the Synthane Corp. of Oaks, Penn., which comprised a paper tube of 1% inch inside diameter with a wall thickness of 1/16 inch, reinforced with a thermoset phenol-formaldehyde resin having the above physical characteristics and a zero gas transmission rate as hereinbefore described was subjected to a 3-month test as a neck tube in a double-walled vacuum insulated storage container during which it was found that the loss of liquefied gas through vaporization induced by heat leak was 1.4 lbs/day as compared to 2 lbs/day employing a stainless steel neck tube in the same type of container under similar conditions. Further, it was found that there was no gas leak to the evacuable insulation space surrounding the inner vessel. Similar tests were preformed employing materials known commercially as Synthane Grade GlO and Gll manufactured by the Synthane Corp. which comprised neck tubes of a glass fiber fabric reinforced with a thermoset epoxy resin. The insulation space was evacuated to an absolute pressure of below about 30 microns of mercury and, after 3 months of continuous testing, the vacuum therein was substantially identical to that at the beginning of the test. The gas imperviousness of neck tubes constructed from these resin impregnated fibrous laminates has been further proven by mass spectographic tests.
The preferred embodiment of this invention employs opacified insulation wherein such insulation substantially completely fills the evacuable insulation space between the outer shell and the inner vessel. However, lower quality insulating systems such as the powder-invacuum insulators or straight vacuum with highly polished outer shell inner and inner vessel outer surfaces may be alternately employed.
The term opacified insulation as used herein refers to a two-component insulating system comprising a low heat conductive, radiation permeable material and a radiant heat impervious material which is capable of reducing the passage of infrared rays without significantly increasing the thermal conductivity of the insulating system. Such opacified insulation is more fully described in U.S. Pat. No. 2,967,152 issued Jan. 3, I96], and copending U.S. application Ser. No. 597,947, filed July 16, 1956, now U.S. Pat. No. 3,007,596 both in the name of L. C. Matsch.
The opacified insulation of the former incorporates the radiation impervious barrier directly into the low heat conductive material. For example, equal parts by weight of copper flakes and finely divided silica might be mixed. The latter material has a very low solid conductivity value but is quite transparent toradiation. The copper flakes serve to markedly reduce the radiant heat inleak.
The latter referenced opacified insulation takes the form of low heat conductive material separated by a multiplicity of radiation-impervious barriers. The low heat conductive material may be a fiber insulation produced in sheet form. Examples include a filamentamicrons. Also, such fibrous materials preferably have a fiber orientation substantially perpendicular to the direction of heat flow across the insulation space. The spaced radiation-impervious barriers may comprise either a metal, metal oxide, or metal coated material, such as aluminum coated plastic film, or other radiation reflective or radiation adsorptive material or a suitable combination thereof. Radiation reflective material, comprising thin metal foils are, particularly suited in the practice of the present invention, for example, reflective sheets of aluminum foil having a thickness between 0.2 millimeters and 0.002 millimeters. When fiber sheets are used as the low conductive material, they may additionally serve as a support means for the relatively fragile radiant heat impervious sheets. For example, it is preferred that an aluminum foil-fiber insulation be spirally wrapped around the inner vessel with one end of the insulation wrapping in contact with the inner vessel, and the other end nearest the outer shell, or in actual contact therewith.
Even though the previously described preferred opacified insulation is more effective than straight vacuum insulation at higher internal pressures (poorer vacuum), its effective thermal insulation life is extended if the vacuum pressure can be maintained at or below a desired level. A gas-removing material such as an adsorbent may be used in the insulation space to remove by adsorption any gas entering through the joints of the 'outer shell. In particular, crystalline zeolitic molecular sieves having pores of at least about 5 Angstrom units in size, as disclosed and claimed in U.S. Pat. No. 2,900,800 issued in the name of P. E. Loveday, are preferred as the adsorbent. They have extremely high adsorptive capacity at the temperature and pressure conditions existing in the insulation space and are chemically inert toward any gases which might leak into the insulation space.
In the preferred embodiment depicted in the FIGURE of the drawing neck tube 10 is constructed of a paper or fabric tube impregnated with a thermoset ry glass material such as glass wool and fiber glass,
preferably having fiber diameters less than about 50 epoxy or phenolic resin in amanner such that neck tube 10 has the aforementioned physical properties. Neck tube 10 is preferably joined to the outer shell 12 of container 14 and to the inner storage vessel 16 by means of rigid annular. support rings 18 and 20 respectively. As shown, neck tube 10 is preferably positioned by annular grooves 17 and 19 in rings 18 and 20, and bonded therein. Rings 18 and 20 are employed to simplify joining the neck tube to the inner vessel and the outer shell inasmuch as it has been found that stronger joints may be constructed by bonding the neck tube in grooves. In this manner, the shear strength of the bonding resin is more fully utilized and a more leak tight joint is achieved. If a relatively weaker joint can be tolerated, the neck tube joints can be formed without the use of grooves. It has been found that A-l2" epoxy resin manufactured by Armstrong Products Co. of Warsaw, Ind., is a suitable bonding agent.
The access opening formed by neck tube 10 is substantially occupied by an annular low heat conductive plug such that liquid vaporized by unavoidable heat leakage will flow out through the annular space between plug 30 and neck tube 10. The vaporizedgas will absorb a substantial part of the heat which would otherwise be conducted into inner vessel 16 by neck tube 10. Low heat conductive plug 30 may be constructed of a material such as foam plastic or cork.
A neck tube constructed of a reinforced thermoset phenol-aldehyde or epoxy resin laminate will not creep or change its shape under varying the temperature conditions. In the preferred embodiment support rings 18 and 20 and neck tube 10 are designed to bearthe vertical loads that are imposed upon the inner vessel and, since rigidity and dimensional stability are important, the properties exhibited, and mentioned above, by these reinforced thermoset resin laminates are desirable.
The bonded joints, between neck tube 10 and annular rings 18 and 20 are preferably formed by curing an application of epoxy resin, such as the previously noted A-l2 brand resin, at temperature of about 150F. In this respect, it should be noted that outer shell 12 and inner vessel 16 should be connected, by means such as welding to annular rings 18 and 20 prior to their assembly with neck tube 10 so that theheat necessary to form the weld joining rings 18 and 20 to outer shell 12 and inner vessel 16 will not damage the bonded joints in the annular grooves of rings 18 and 20. Therefore, to assemble this arrangement, inner vessel 16 with its welded ring 20 is first attached to the support member 22 within the lower section of outer shell 12. Neck tube 10 is then placed in the annular groove of ring 20 and an upper section of outer shell 12, with annular ring 18 attached, is placed into position, elastically elongated and preferably girth welded at 11 to its first lower segment. The resulting joints in the annular grooves 17 and 19 of rings 18 and 20 are then cured, employing the epoxy resin as the neck tube joint bonding agent. Insulation space 24 is preferably evacuated similtaneously with the curing process.
It has been found that the ends of the neck tube and the annular grooves should be sandblasted prior to bonding to provide sufficiently roughened surfaces for proper bonding thereof. The sandblasting may be accomplished by projecting l20-mesh aluminum oxide particles against the surfaces of the grooves at a velocity of about 500 fps.
What is claimed is;
1. In a low temperature storage container having an outer shell and an inner storage vessel each with an upper opening wherein the two openings are vertically aligned and with said inner storage vessel and outer she I sized to enclose an intervening vacuum insulation space, the improvement comprising a cylindrical neck tube with opposite ends respectively gas-tightly sealed to the edges of said upper openings in the outer shell and inner vessel so as to provide a relatively wide access hole from the atmosphere to the interior of said inner vessel, said neck tube being formed of a substantially gas impervious material with the outer wall- Compressive strength-at least 10,000 PSI Tensile strength-at least 8,500 PSI Specific heat-between 0.26-0.40
Thermal conductivitybetween 0.0007-0.00 l 2 cal/sec/cmIdeg. C/cm.
2. A storage container according to claim 1 in which the neck tube is formed of paper reinforced with a thermoset phenol-formaldehyde resin.
3. A storage container according to claim 1 in which the neck tube is formed of glass fiber reinforced with a thermoset epoxy resin.
4. A storage container according to claim 1 in which the neck tube is formed of material having a specific gravity of at least 1.10.
5. In a low temperature vacuum insulated storage container having an outer shell and an inner storage vessel each with an upper opening wherein the two openings are vertically aligned, the improvement comprising a cylindrical neck tube with opposite ends respectively gas-tightly sealed to the edges of said upper openings in the outer shell and inner vessel so as to provide a relatively wide access hole from the atmosphere to the interior of said inner vessel, said neck tube being formed of a substantially gas impervious material selected from the group consisting of paper reinforced with a thermoset phenol-formaldehyde resin, glass fiber reinforced with a thermoset epoxy resin, and glass fiber reinforced with a thermoset polyester resin, said neck tube being loaded in tension by said inner vessel as the sole suspension means therefor and wherein support rings with grooves that face each other axially of the container are connected to the edges of said upper openings in the outer shell and inner vessel, and the opposite ends of said neck tube are positioned and gas-tightly sealed in said grooves.
Claims (5)
1. In a low temperature storage container having an outer shell and an inner storage vessel each with an upper opening wherein the two openings are vertically aligned and with said inner storage vessel and outer shell sized to enclose an intervening vacuum insulation space, the improvement comprising a cylindrical neck tube with opposite ends respectively gas-tightly sealed to the edges of said upper openings in the outer shell and inner vessel so as to provide a relatively wide access hole from the atmosphere to the interior of said inner vessel, said neck tube being formed of a substantially gas impervious material with the outer wall thereof sealing said vacuum insulation space and selected from the group consisting of paper reinforced with a thermoset phenol-formaldehyde resin, glass fiber reinforced with a thermoset epoxy resin, and glass fiber reinforced with a thermoset polyester resin, said neck tube being loaded in tension by said inner vessel as the sole suspension means therefor and having the following physical properties: Compressive strength-at least 10,000 PSI Tensile strength-at least 8,500 PSI Specific heat-between 0.26-0.40 Thermal conductivity-between 0.0007-0.0012 cal/sec/cm2/deg. C/cm.
2. A storage container according to claim 1 in which the neck tube is formed of paper reinforced with a thermoset phenol-formaldehyde resin.
3. A storage container according to claim 1 in which the neck tube is formed of glass fiber reinforced with a thermoset epoxy resin.
4. A storage container according to claim 1 in which the neck tube is formed of material having a specific gravity of at least 1.10.
5. In a low temperature vacuum insulated storage container having an outer shell and an inner storage vessel each with an upper opening wherein the two openings are vertically aligned, the improvement comprising a cylindrical neck tube with opposite ends respectively gas-tightly sealed to the edges of said upper openings in the outer shell and inner vessel so as to provide a relatively wide access hole from the atmosphere to the interior of said inner vessel, said neck tube being formed of a substantially gas impervious material selected from the group consisting of paper reinforced with a thermoset phenol-formaldehyde resin, glass fiber reinforced with a thermoset epoxy resin, and glass fiber reinforced with a thermoset polyester resin, said neck tube being loaded in tension by said inner vessel as the sole suspension means therefor and wherein support rings with grooves that face each other axially of the container are connected to the edges of said upper openings in the outer shell and inner vessel, and the opposite ends of said neck tube are positioned and gas-tightly sealed in said grooves.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US88815169A | 1969-12-29 | 1969-12-29 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3698589A true US3698589A (en) | 1972-10-17 |
Family
ID=25392620
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US888151A Expired - Lifetime US3698589A (en) | 1969-12-29 | 1969-12-29 | Cryogenic storage apparatus |
Country Status (1)
Country | Link |
---|---|
US (1) | US3698589A (en) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4120421A (en) * | 1976-03-25 | 1978-10-17 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Containers for cryogenic liquids |
US4187955A (en) * | 1977-03-09 | 1980-02-12 | L. & C. Steinmuller Gmbh | Armored pipe connected to a steel lining of a prestressed cast pressure tank |
EP0209003A2 (en) * | 1985-07-17 | 1987-01-21 | Messer Griesheim Gmbh | Double-walled insulated container for the storage of low-boiling liquefied gases |
US4687118A (en) * | 1985-02-25 | 1987-08-18 | Rheem Manufacturing Company | Foam insulated tank |
USRE33968E (en) * | 1985-02-25 | 1992-06-23 | Rheem Manufacturing Company | Foam insulated tank |
US20030029877A1 (en) * | 2001-07-30 | 2003-02-13 | Mathur Virendra K. | Insulated vessel for storing cold fluids and insulation method |
US20040020932A1 (en) * | 2000-10-04 | 2004-02-05 | Klaus Brunnhofer | Tubular conduit or container for transporting or storing cryogenic |
US20040089580A1 (en) * | 2002-11-06 | 2004-05-13 | Hitoshi Ueda | Double-layer vacuum container |
US6832636B2 (en) | 2001-09-27 | 2004-12-21 | Graeme Harrison | Fuel nozzle lever, a fuel nozzle and a method of operating a fuel nozzle |
US20160137272A1 (en) * | 2013-06-19 | 2016-05-19 | Kawasaki Jukogyo Kabushiki Kaisha | Double-shell tank and liquefied gas carrier ship |
US20180283769A1 (en) * | 2017-03-29 | 2018-10-04 | Bruker Biospin Ag | Cryostat arrangement comprising a neck tube having a supporting structure and an outer tube surrounding the supporting structure to reduce the cryogen consumption |
US10337670B2 (en) * | 2014-06-27 | 2019-07-02 | Kautex Textron Gmbh & Co. Kg | Pressure vessel |
EP3699476A4 (en) * | 2017-10-16 | 2021-07-07 | Kawasaki Jukogyo Kabushiki Kaisha | Double shell tank, and ship |
-
1969
- 1969-12-29 US US888151A patent/US3698589A/en not_active Expired - Lifetime
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4120421A (en) * | 1976-03-25 | 1978-10-17 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Containers for cryogenic liquids |
US4187955A (en) * | 1977-03-09 | 1980-02-12 | L. & C. Steinmuller Gmbh | Armored pipe connected to a steel lining of a prestressed cast pressure tank |
US4687118A (en) * | 1985-02-25 | 1987-08-18 | Rheem Manufacturing Company | Foam insulated tank |
USRE33968E (en) * | 1985-02-25 | 1992-06-23 | Rheem Manufacturing Company | Foam insulated tank |
EP0209003A2 (en) * | 1985-07-17 | 1987-01-21 | Messer Griesheim Gmbh | Double-walled insulated container for the storage of low-boiling liquefied gases |
EP0209003A3 (en) * | 1985-07-17 | 1987-11-19 | Messer Griesheim Gmbh | Double-walled insulated container for the storage of low-boiling liquefied gases |
US20040020932A1 (en) * | 2000-10-04 | 2004-02-05 | Klaus Brunnhofer | Tubular conduit or container for transporting or storing cryogenic |
US20030029877A1 (en) * | 2001-07-30 | 2003-02-13 | Mathur Virendra K. | Insulated vessel for storing cold fluids and insulation method |
US6832636B2 (en) | 2001-09-27 | 2004-12-21 | Graeme Harrison | Fuel nozzle lever, a fuel nozzle and a method of operating a fuel nozzle |
US7284674B2 (en) * | 2002-11-06 | 2007-10-23 | Tiger Corporation | Double-layer vacuum container |
US20040089580A1 (en) * | 2002-11-06 | 2004-05-13 | Hitoshi Ueda | Double-layer vacuum container |
US20090114335A1 (en) * | 2002-11-06 | 2009-05-07 | Tiger Corporation | Double-layer vacuum container |
US7797807B2 (en) | 2002-11-06 | 2010-09-21 | Tiger Corporation | Double-layer vacuum container |
US20160137272A1 (en) * | 2013-06-19 | 2016-05-19 | Kawasaki Jukogyo Kabushiki Kaisha | Double-shell tank and liquefied gas carrier ship |
US10207775B2 (en) * | 2013-06-19 | 2019-02-19 | Kawasaki Jukogyo Kabushiki Kaisha | Double-shell tank and liquefied gas carrier ship |
US10337670B2 (en) * | 2014-06-27 | 2019-07-02 | Kautex Textron Gmbh & Co. Kg | Pressure vessel |
US20180283769A1 (en) * | 2017-03-29 | 2018-10-04 | Bruker Biospin Ag | Cryostat arrangement comprising a neck tube having a supporting structure and an outer tube surrounding the supporting structure to reduce the cryogen consumption |
CN108692187A (en) * | 2017-03-29 | 2018-10-23 | 布鲁克碧奥斯平股份公司 | Cryostat arrangement system |
EP3699476A4 (en) * | 2017-10-16 | 2021-07-07 | Kawasaki Jukogyo Kabushiki Kaisha | Double shell tank, and ship |
US11247752B2 (en) | 2017-10-16 | 2022-02-15 | Kawasaki Jukogyo Kabushiki Kaisha | Double-shell tank and ship |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3698589A (en) | Cryogenic storage apparatus | |
US7562534B2 (en) | Cryogenic aerogel insulation system | |
US4394929A (en) | Cryogenic liquid storage container having an improved access conduit | |
US3369826A (en) | Cryogenic fluid transfer conduit | |
CA2037810C (en) | Cryogenic storage container | |
US4606196A (en) | Vacuum insulation system | |
US3289423A (en) | Load support means for thermally insulated containers | |
US5419139A (en) | Composite cryogenic tank apparatus | |
US4215798A (en) | Container for cryogenic liquid | |
WO2003072684A1 (en) | Microsphere insulation systems | |
EP0099574B1 (en) | Composite thermal insulator | |
US9279540B2 (en) | Web insulation system, valve for a web insulation system, and a storage container using the web insulation system | |
US3319433A (en) | Rectangular dewar | |
US4667390A (en) | Vacuum insulation system method of manufacture | |
US3134237A (en) | Container for low-boiling liquefied gases | |
JP5044310B2 (en) | Low temperature liquefied gas storage tank | |
US3230726A (en) | Elastomeric connecting means for double-walled containers | |
US2998708A (en) | Container for low temperature liquids | |
JPH0254479B2 (en) | ||
CN116202015B (en) | Multilayer heat insulation composite structure for double-wall low-temperature container and coating process thereof | |
EP0193795B1 (en) | Introductory process for an adsorbing material | |
US3406857A (en) | Insulated plastic vessel | |
US3818715A (en) | Heat-insulating constructions | |
KR101972915B1 (en) | Large storage tank for cryogenic liquid having insulating layer | |
US3207353A (en) | Cryogenic liquid storage containers |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: HARSCO CORPORATION, HARRISBURG, PA. A CORP. OF DE. Free format text: ASSIGNMENT OF ASSIGNORS INTEREST. SUBJECT TO LICENSE RECITED;ASSIGNOR:UNION CARBIDE CORPORATION, A CORP. OF N.Y.;REEL/FRAME:004500/0021 Effective date: 19850722 |