US3274788A

US3274788A - Cryogenic liquid storage vessel

Info

Publication number: US3274788A
Application number: US463792A
Authority: US
Inventors: Thomas E Hoffman; Walter H Hogan; Robert M Lucas; Jr Raymond W Moore
Original assignee: Arthur D Little Inc
Current assignee: Arthur D Little Inc; BankBoston NA
Priority date: 1965-06-14
Filing date: 1965-06-14
Publication date: 1966-09-27
Anticipated expiration: 1983-09-27

Description

Sept. Z7, 1966 T. E. HOFFMAN ET AL CRYOGENIC LIQUID STORAGE VESSEL 3 Sheets-Sheet l Filed June 14, 1965 Thomas E. Hoffman Wolter H. Hogan INVENTORS Robert M. Lucas BY Raymond W. Moore,Jr.

Attgxney Sept. 27, 1966 T. E. HOFFMAN ET AL CRYOGENIC LIQUID STORAGE VESSEL Filed June 14, 1965 5 Sheets-Sheet 2 Ullmlllll L.

Fig.

Thomas E. Hoffman Wolrer H. Hogan Roberr Nl. Luces INVENTORS Raymond W. Moore, Jr.

Attorney Sept 27, 1966 T E* HQFFMAN ET AL `.3,274,788

CRYOGENIG LIQUID STORAGE VESSEL 5 Sheets-Sheet 5 Filed June 14, 1965 Hoffman INVENTORS Thomos E. Wolter H. Hogan Roberll IVI. Lucas BY Raymond W. Moore,Jr.

AT orney United States Patent O 3,274,788 CRYOGENIC LIQUID STORAGE VESSEL Thomas E. Hoffman, Marblehead, Walter H. Hogan, Wayland, Robert M. Lucas, Melrose, and Raymond W.

Moore, Jr., Brookline, Mass., assignors to Arthur D.

Little, inc., Cambridge, Mass., a corporation of Massachusetts Filed June 14, 1965, Ser. No. 463,792 15 Claims. (Cl. 62-45) This invention relates to a cryogenic storage Vessel and more particularly to a Dewar-type vessel `for storing cryo- `genic lluids.

In the hand-ling and storing of cryogenic lluids, it is of course necessary to provide vessels which exhibit a minimum heat leak from the surrrounding atmosphere into the cryogenic lluid which is contained therein. Any undue amount of heat leak causes excess boil-off and hence loss of the cryogenic lluid. A number of -vessels have been built which may he referred `to as the Dewar-type, le., the type which basically consists of an inner and outer vessel having the spacing between the two vessels sealed and evacuated. Many of these vessels are in use today and a variety of designs and constructions are available. However, because of the necessity for supporting the innner vessel lwith a support system that represents a minimum heat transfer path from the outer to the inner vessel, Imost of the Dewar-type vessels now available are not particularly rugged in construction. This means that these vessels cannot `be readily handled and transported without the exercise of considerable care. Moreover, most of these vessels have fairly low capacities, e.g., -50 liters. It would therefore be desirable to have a Dewar -storage vessel which is rugged, can withstand a considerable amount of handling, and can be fabricated in sizes from small up to extremely large, e.g., 3,000 liters.

It is therefore a primary object of this invention to provide an improved Dewar-type cryogenic storage vessel. It is another object `of this invention to provide such a storage vessel which is relatively rugged and highly eflicient in that the boil-olf rate of cryogenic liquid stored therein is maintained at a minimum. It is yet another object of this invention to provide a cryogenic storage vessel of the character described which incorporates a unique lateral support system. It is a further object to provide such a vessel which does not require an externally supplied coolant fluid. It is yet another object of this invention to provide a cryogenic storage vessel which may be constructed in a wide range of volumes and may be made to contain extremely large quantities of a cryogenic liquid. `It is still a further object of this invention to provide such a storage vessel which is so designed as to make is particularly suitable for use as a vessel in which the cryogenic lluid is liquefied directly. Other objects of the invention will in part be obvious and will in part be apparent hereinafter.

The invention accordingly comprises the features of construction, combination of elements and arrangement of parts which will be exemplified in the constructions hereinafter set forth, and the scope of the invention will 4be indicated in the claims.

lFor a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which FIG. 1 is a longitudinal cross-section of the cryogenic storage vessel of this invention;

vFIG. 2 is a cross-sectional detail of the bottom lateral support system of the storage vessel;

iFIG. 3 is a cross-section taken along lines 3-3 of FIG. 2 showing a section of the bottom support system;

c ICC FIG. 4 is a cross-section taken through the lateral support bands;

IFIG. S is a cross-sectional detail of the upper lateral support system;

IFICl. 6 is a fragmentary cross-section of a portion of the insulation used;

FIG. 7 is a side elevational view, partly cut away, of the top of the storage vessel;

FIG. -8 is a top plan view of the upper part of the stora'ge vessel; and

IFIG. 9 is a diagram of the alternative ow paths of the vented gas.

In keeping with the more or 'less basic Dewar design, there is provided in the cryogenic vessel of this invention an inner and outer vessel having the space between evacuated. Within this evacuated space is a radiation shield which is cooled hy boiled off vapor from the innner vessel, the cooling being extended to include the neck of the inner vessel over certain selected areas. IInsulation is wrapped around the radiation shield and additional glass wool insulation is supplied around the neck. The entire weight of the inner vessel, the radiation shield and the insulation is supported through the neck and hence at the -top of the vessel. All of the lateral support Within the vessel for the inner vessel and the radiation shield is .provided by a unique type of support system positioned at the bottom and top of the Dewar.

Turning now to FIG. 1 the general assembly of the cryogenic storage vessel of this invention may be seen. There is provided an inner vessel 10 which contains the cryogenic liquid |11. IEntirely surrounding the inner vessel 10 is an outer vessel A12 which delines with the inner vessel a fluid-tight, evacuatable space 13. Within this space and surrounding the inner vessel is a cooled radiation shield 15 and around the radiation shield is wrapped insulation 16 which conforms essentially to the configuration of the radiation shield. yAs will be -seen in FIG. 5 the preferred form of the insulation is a structure which consists of alternating coarse mesh l17 and aluminum foil 18, assembled to form a multilayered insulation in accordance lwith the teaching of -U.S. Patent 3,152,033. The mesh is preferably formed of ber glassl coated with a polyvinyl resin from which at least some, and preferably all, of the plasticizer for the resin had been leached with a solvent such` as heptane. leaching out of thel resin plasticizer materially reduces or eliminates outgassing; but the resin still retains a sufficient degree of thermoplasticity to make it heat weldable so that the insulation in being wrapped around the top and bottom of the radiation shield can be pleated to permanently conform to its con-figuration. The low thermal conductivity mesh furnishes spacing means `-for the multiple aluminum radiation shields. It is preferable to use about 30 layers of mesh and aluminum. However, more or less may be ernployed. The bottom of the outer vessel under this insulation is lilled with glass wool |14.

Returning now to FIG. 1, it will .be seen that a neck 19, preferably of fairly large diameter, communicates between the interior of the inner vessel and whatever connections are desired to be made with it as will be described below. Neck 19 delines a relatively large diameter inlet 20 into which an external Joule-Thomson valve with its attendant heat transfer passages may be inserted, thus making it possible to liquefy gases, including helium, directly into the storage vessel. An external Joule-Thomson lvalve suitable for insertion through neck passage 20 into the inner vessel is described in a copending patent application Serial No. 307,073, now Patent Number 3,201,947, led in the names of Arthur H. Post and Milton H. Streeter and assigned to .the same assignee as the present application.

The entire cryogenic storage vessel is preferably permanently mounted on a support system which in FIG. l is seen to comprise horizontal supports 21 (of which there are four) and vertical supports 22.

The inner vessel is conveniently formed in three sections, namely a central cylindrical section 23, an upper domed section 24, which is joined to the cylindrical section by means of welding and -an inner band 25, and a lower rounded section 26, joined to the cylindrical section 23 through a welding and a similar inner band 27. The inner vessel, as Well as the radiation shield, is supported by a lower support system generally indicated by the numeral 30 in FIG. l. This lower support system is shown in detail in FIG. 2 and will be described subsequently. Positioned below a central portion of the bottom of the inner vessel section 26 is a wide annular dish 31. The spacing between this dish 31 and the external wall of the inner vessel section 26 is filled with absorbent material 32 such as activated charcoal. It will be appreciated that in this position the absorbent is maintained at a temperature which approximates that of the cryogenic fluid thus providing `an efficient cold trap. The lower support system 30 has attached to it three bands 33 of low conductivity which are anchored to a support 34, This portion of the bottom lateral support system is also shown in detail in FIG. 2 and will be described subsequently in connection with the discussion of that figure.

The radiation shield is preferably formed of three sections comprising a thin central Icylindrical section 35, a thicker conically shaped top section 36 and a thicker dish-shaped bottom section 37. This radiation shield is cooled by vapor from the inner vessel. This vapor accumulates above the liquid iin area 39 and is removed through coil 40 which, it will be seen, is wound first around the vbottom of the neck 19 near where it joins the inner vessel, then once around the radiation shield. In being wrapped around the radiation shield this vapor coolant tubing 40 passes through top opening 41 to the outer surface of the shield, then through bottom opening 42 to form physical contact around about one-half of the inner surface of the section 37, then again out through bottom opening 43 to physically contact the outer surface of central section 35 and top section 36 on the opposite side. The heat transfer path is, of course, through the walls of the tubing 40 from the walls of the radiation shield with which it makes physical contact. Tubing 40 is then returned to the interior of the radiation shield through opening 44, passes through a collar 45 which is positioned around the neck 19, and then is Wound :about the upper section of the neck so that it establishes thermal contact with the neck at a number of locations shown in FIG. 3 to be in three places-47, 48 and 49. Tubing 40 then passes through a sealing member 46 to be connected to a T joint as described with reference to FIGS. 7-9.

The outer vessel, like the inner Vessel, is formed of three sections namely a central section 50 which is attached to the upper dome section 51 by an internally located joining angle ring 52 and to the lower dished section 53 through another internally located joining ring 54. All of these sections are welded and are of course fluid-tight. In the bottom section 53 of the outer vessel there is a bottom plug 56 and a suitable joining conduit 57 for :attachment to an evacuation line. This conduit is sealed with a suitable plug 58. The outer vessel has an outer neck 60 which is sealed by plug 61 and over which an instrument assembly box fits as shown in FIG. 7.

Located around the upper section of the outer vessel are a series of ears 62 which are used for lifting the storage vessel. The Dewar may also have longitudinal bar handles 63 (FIG. 7 shows one of these) which are affixed to the horizontal supports 21 and to the upper section of the outer vessel. These are, of course, optional and any suitable means for handling the vessel may be used,

The neck which extends from the inner vessel and which, as previously stated, supports the weight of the inner vessel, the radiation shield and the insulation, is joined to the inner vessel through a series of

annular bushings

65 and 66 and a collar 67. It is joined to the radiation shield through collar 45 and a suitable bushing 68 (see FIG. 5) and to the plug 61 through the bushing 69. Around that portion of the neck which extends above the radiation shield there is placed a sleeve 72 which defines an annular space 73 with the neck. This is in fluid communication with the main evacuated space 13 through a right-angle tubing member 74 which opens into a narrow -passageway 75 defined between the internal wall of the outer vessel and glass wool packing 76 which is retained within a screening 77.

As in the case of the bottom portion of the vessel, the upper portion is laterally supported through the radiation shield by means of a low thermal conductivity band 80 fastened to an anchoring system 81, this lateral support system being shown in detail in FIG. 5.

Turning noW to FIGS. 2 and 3 the bottom lateral support system may be described in detail. -In these figures like numbers refer to like elements shown in FIG. 1. At the center of the bottom section 26 of the inner vessel there is placed a sleeve which makes a fluid-tight seal with this bottom section and which extends up into the inner vessel and the cryogenic fluid stored therein. A sleeve 85 is attached to the bottom section 26 through an annular ring 86 and is sealed on the bottom by a plug 87 which is integral with a vertical downwardly extending main inner vessel lateral support stud 88. Surrounding this lateral support stud 88 is a support stud tubing 90l which at its upper end is integral with a relatively thick flange 91. On the outer or bottom surface of the flange 91 the radiation shielding bottom section 37 is aixed through use of an annular ring 92. The support stud tubing is closed with an end cap 93 which can be removed for insertion of portions of the support system, and serves as a radiation barrier. Around the inner wall of the tubing 90 are three lands 95 (shown in FIG. 3) which are in position t-o contact a Pyrex glass ball 96. The lateral support stud 88 has as extensions three fingers 89 on which are located lands 94 which alternate in position with lands 95. Although FIGS. 2 and 3 show the use of three lands 94 and three lands 95, it is within the scope of this invention to use more than three -of each. The lands in each set should be equally spaced around the circumference of the ball and those of lone set yshould alternate with those of the other set. Lands 94 provide contacting surfaces 100; while lands 95 provide contacting surfaces 101. The ball 96, which rests upon a ball support 97, has a circumference which is just slightly less than the circumference defined by the

surfaces

100 and 101 of the lands. This means that at any one time, the surface of ball 96 makes contact with less than allot the surfaces of the lands. For example in FIG. 3, which illustrates the use of a total of 6 lands, ball 96 is seen to contact only a single land 94 and -a single land 95. This continuously minimizes the amount of contacting surfaces and hence any heat leaks. Ball support 97 has associated with it an encircling ring 98 which serves to tie together fingers 89 so that any radial loading put on one of the fingers and its -associated land .by the ball is also transmitted to the other fingers. Through a snap ring 99 the ball support is positioned and held to the three fingers of the lateral support stud 88.

It will be seen that lands 94 are associated through stud `88, plug 87, sleeve 85 and collar 86 with the positioning yof the inner vessel; IWhile lands are associated through tubing 90, fiange 9l1 and ring 92 with the positioning of the radiation shield. Ball 96 acting alternately on

lands

94 and 95 maintains the inner vessel and radiation shield `in proper relative alignment and the three bands tl08 maint-ain the inner Vessel and radiation shield in lateral alignment with the outer vessel, thus providing for all -of the lateral support.

yIt is normally desirable to be able continuously to monitor the liquid level within the storage vessel. There is therefore provided in this storage vessel a means for continuously determining the pressure at essentially the bottom of the liquid and above the liquid level. The actual liquid level may then be determined since it is a function of the difference of .these two pressures. There is therefore provided a capillary tubing 102 which communicates with the bottom of the liquid 1.1 through a hole y103 drilled in the sleeve `85. This capillary 102 continues up through the vessel and communicates 'with a pressure dilferential measuring device shown and described in connection with FIGS. 7 and `8.

FIGS. 2 and 4 also illustrate in detail the unique lateral support system associated with the bottom section of the storage vessel. Around the support stud tubing 90 is aixed an annular collar 105 which has machined in it t-hree recesses 106. Only one of these is shown in FIG. 2, but it will be appreciated that they are spaced 120 apart and thus provide for a balanced three-directional support for the inner vessel and the radiation shielding. A spool 107 passes through the recess 106 and `around it is Wound a band, one-half of which is shown in FIG. 2. \FIG. 4 shows the entire band `108 in cross-section. This band 108 is preferably formed of monolament fiber glass embedded in an epoxy resin. The other terminal for the band is anchored to the inner wall of the outer vessel through the support 34, as is shown in =FIG. 1. A U-shaped anchoring piece 109 has a pin `1.10 extending through it and the band 108 passes around the pin. The band anchoring piece 109 is held to the support 34 through a bolt 112, nuts 113 and spherical alignment washer 1v1-4, an arrangement which provides for band adjustments.

A mesh `1111 extends horizontally Within the outer vessel directly below themultiple-radiation lshield insulation '16 and around the bottom edge of it. Glass wool insulation 14 is packed within the outer vessel below this mesh 111 and additional yglass wool 14a may be used to ll the space between the insulation 16 and the upper surface of the mesh.

yThe lateral support system at the top of .the vessel is similar in construction to that usedfat ythe bottom, and, as in the case of the bottom lateral support, three bands are used. This top lateral support system is shown in detail in FIG. 5. It Will be seen from this fragmentary cross-sectional detail of FIG. 5 that the upper lateral support system is attached'to a bushing `68 through which a suitable bolt 120 is passed to attach the upper end of the upper section 36 of the radiation shield to the collar 45 which in turn is mounted on the neck '19. Attached to the .bushing -68 is an annular ring =121 which has a recess A122 into which is fitted a pin 123. The ber glassepoxy band 124 fits around this pin and a second pin 127 which is held in a yoke 125 having a recess 126. The yoke 125 is in turn aixed to the peripheral attaching means generally indicated bythe numeral 81, through an angle piece 130 which is welded to a support y13:1. `This Vattachment is likewise achieved through the use of a bolt y133, a nut 1'34 and spherical alignment washer i135 for providing adjustments.

Turning now to FIGS. 7-9, it will be seen how external connections are effected with the inner vessel of the cryogenic storage vessel. An instrument assembly box 138 Vfitted with a fluid-tight sealing bushing 139 fits over the upper end of .the neck 219 and sits on the top of the outer vessel. The tubing y40 which vents the cold vapor from the inner vessel extends through this instrument box, and as will be seen in FIG. 9 there is provided a choice for the path of the vented gases. This is done through the use of a T-joint. The lirst alternative of gas dow, which is the one used while liquefaction is taking place within t-he storage vessel, is through a valver140 which is in uid communication with a flow meter |142.

This How meter is preferably of the type which permits setting an indication of a desired gas iiow. By determining `the normal venting of gas through this flow meter when the storage vessel contains a cryogenic liquid and is being used only for storage, a normal boil-off rate is noted. The indicator of flow meter 142 is then set at this normal boil-01T rate to serve as aY basis for check-` ing, during Aliquefaction within the vessel, to determine whether there is a proper ow of gas through the vent tube to keep the radiation shield cold.

From the lio-w meter 142 the vented gas passes through a muffler 144 and then by way of a suitable conduit (not shown) into the pressure circuit of a liquetier or other apparatus. The purpose of the mufer is to reduce or entirely eliminate the pulsations which may be present in the low-pressure line leading to the compressor. Normally as a compressor takes in gas periodically it develops pulses, and transmission of such pulses back int-o the storage vessel must be minimized because they interfere with the proper operation of dow meter 142 and set up unwanted thermal oscillations.

The other alternative path of .the vented gas from tubing 40 is directly to the atmosphere in which case valve '140 is closed and the gas is taken to the atmosphere by way of a manual valve 146 and relief valve 147. By maintaining .the flow of gas only outwardly, no moist air is permitted to enter the system. This alternative route for the vented gas is used when the vessel is used only for storage and not liqueactiOn.

As pointed out in the description of FIG. 2, there is a small capillary 102 which is open to the inner vessel and which communicates 'with a differential pressure gage. This capillary 102 passes through the .top of the instrument assembly box and communicates with differential pressure gage 15|1 as will be seen in FIGS. 7 and 8. Capillary 148, which communicates with the inner volume ofthe inner vessel through neck -19 and the T connector A154, leads into the differential pressure gage '151. By determining the difference in the pressures at the bottom of the liquid and at the .top of the inner vessel it is possible to read out directly the amount of liquid contained Within the inner vessel on a suitably calibrated gage.

:In order to provide suitable inlet connections into the inner vessel, there is provided a T connector |154 which slips 'down over the fit-ting bushing 139 of the instrument assembly box. This is shown in detail in FIG. 7. Two

relief valves

156 and 157 are connected to the T connector for the purpose of providing alternative pressure release routes for gas which might accumulate in the inner vessel. A conduit 159 with a suitable 'fitting gland |160 is provided for inserti-on of a draw-off tube to remove cryogenic liquid from the storage vessel. In similar fashion a conduit 161 is provided with a gland connector 162 for making suitable connections with an external Joule- 'Ihomson va-lve assembly which is inserted into the storage vessel for |liquefaction within the vessel. It is, of course, possible to provide other connecting lines into the storage vessel, as well as to close these off, but it should be noted that with the large diameter neck provided it is possible to include more than one such connection and to choose among a number of connections depending upon the use to which the storage vessel is put. An auxiliary T connector 163 is connected to the main T connector 154 and provides for connecting capillary i148 .to the volume of the inner vessel and also serves as a means to connect a service valve i164, the purpose of which is to provide for pressurizing or evacuating the inner vessel if this is desired. Finally there is also connecte-d to this T connector a pressure gage 165 which permits continuous monitoring of the gas pressure in the inner vessel.

It will be seen from the above description that the Dewar-type cryogenic storage vessel of this invention provides a rugged device which can be moved and handled without any undue care. The upper and lower lateral support systems assure lateral alignment of the cryogenic storage vessel at all times. The inner Vessel may conveniently be constructed of stainless steel which is known to have excellent structural strength at the very low temperatures at which it is maintained when a cryogenic liquid is contained therein. By providing a relatively large-diameter neck it is possible to make a number of different types of connections into the interior of the vessel. Moreover, the thermal design of the vessel is such as to minimize heat leaks into any cryogenic liquid stored therein. At the same time it makes the most eicient use of the cold boiled-off vapor by cooling the bottom end of the neck, then the radiation shield and finally the top end of the neck. The ball support system achieves maximum support with essentially minimum thermal contact. Finally the cryogenic vessel of this invention is adaptable for construction in a wide range of sizes from relatively small to very large.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are eiciently attained and since certain changes may be made in the above construction without departing from the scope of the invention it is intended that all matter contained in the above description or shown in the accompanying drawings should be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

We claim:

1. In a cryogenic liquid storage vessel formed of an inner vessel having a neck section, an outer vessel and an evacuated space therebetween in which is located radiation shield means, a lateral support system formed of (a) a bottom lateral support comprising in combination (l) a vertically disposed stud afxed to the bottom of said inner vessel and having depending therefrom at least three equally spaced eX- tensions forming curved contacting inner vessel lands,

(2) a sheath surrounding the bottom portion of said stud, aliixed to said radiation shield and having on its internal walls at least three curved and equally spaced contacting lands in the same plane as said inner vessel lands and alternating in position With said inner vessel lands,

(3) a spacer body of low thermal conductivity positioned to contact the surface of said lands, whereby said inner vessel and said radiation shield are maintained in relative alignment, and

(4) at least three, low thermal conductivity bands equally spaced connecting said sheath and the internal wall of said outer vessel; and

(b) a top lateral support, comprising in combination (l) connector means joining said radiation shield means with said neck section of said inner vessel, and

(2) at least three, low thermal conductivity bands equally spaced connecting said connector means and the internal wall of said outer vessel.

2. A cryogenic liquid storage vessel in accordance with claim 1 wherein said spacer body is a spherical glass ball.

3. A cryogenic liquid storage vessel in accordance with claim 1 wherein said extensions depending from said stud are held together at their terminal end by a map ring whereby any radial loading put on one extension and its associated inner vessel land is transmitted to the .other of said c2$ @1 1$.i0 11$.

4. A cryogenic liquid storage vessel in accordance with claim 1 wherein each of said bands is in the form of a continuous belt held at each end by horizontally disposed `end members, the position of said end-members associated with the internal wall of said outer vessel being adjustable.

5. A cryogenic liquid storage vessel in accordance with claim 1 wherein said bands are formed of monolament fiber glass embedded in an epoxy resin.

6. A cryogenic liquid storage vessel, comprising in combination (a) an inner vessel adapted to contain a cryogenic liquid and having a neck for communication with the interior thereof;

(b) an outer, fluid-tight vessel surrounding said inner vessel and a portion' of said neck and defining therewith an evacuatable space;

(c) a radiation shield around said inner vessel within said evacuatable space and attached to said neck of said inner vessel through connector means;

(d) insulation wrapped around the outside of said radiation shield; and

(e) a lateral support system formed of (l) a bottom lateral support comprising (i) a vertically disposed stud afxed to the bottom of said inner vessel and having depending therefrom at least three equally spaced extensions forming curved contacting inner vessel lands,

(ii) a sheath surrounding the bottom portion of said stud, affixed to said radiation shield and having on its internal walls at least three curved and equally spaced contacting lands in the same plane as said inner vessel lands and alternating in position with said inner vessel lands, v

(iii) a spacer body of low thermal conductivity positioned to contact the surface of said lands, whereby said inner vessel and said radiation shield are maintained in relative alignment, and

(iv) at least three, low thermal conductivity bands equally spaced connecting said sheath and the internal wall of said outer vessel; and

(2) a top lateral support comprising at least three, low thermal conductivity bands equally spaced connecting said connector means and the internal wall of said outer vessel.

7. A cryogenic liquid storage vessel in accordance with claim 6 further characterized by having vapor coolant tubing means adapted to withdraw cold vapor from within said inner Vessel and to cool in order, through out-of-contact heat exchange, said neck near its juncture with said inner vessel, said radiation shield, yand the upper portion of said neck enclosed within said outer vessel.

8. A Cryo-genie liquid storage vessel in accordance with claim 6 further characterized by having additional insulation located between `the upper portion of said neck enclosed in said outer vessel and the internal w-all of said outer vessel and being spaced from said neck and said internal wall thereby to prevent the fluid isolation of any portion of said evacuatable space.

9. A cryogenic liquid storage vessel in accordance with claim 6 further characterized by having additional insulation lilling the bottom portion of said outer vessel and separated from said insulation Wrapped around said radiation shield by a coarse mesh member.

10. A cryogenic liquid storage vessel in accordance with claim 6 further characterized by having la plate member maintained in spaced relationship from the central portion of the external Wall ofthe bottom of said internal vessel and an adsorbent material filling the volume therebetween.

11. A cryogenic liquid storage vessel in accordance with claim 6 wherein said insulation wrapped -around said radiation shield comprises a multiplicity of aluminum foil sheets maintained in spaced relationship by a coarse netting formed of polyvinyl-coated glass fibers, at least a portion of the plasticizer of said polyvinyl coating having been removed by leaching with a solvent.

12. A cryogenic liquid storage vessel in accordance with claim 11 wherein said insulation in being wrapped around said radiation shield is heat welded through said netting to permanently conform to fthe conliguration of said radiation shield.

13. A cryogenic liquid storage vessel, comprising in combination (a) an inner vessel adapted to contain a cryogenic liquid and having a neck for communication with the interior thereof;

(b) an outer, Huid-tight vessel surrounding said inner vessel and a portion of said neck and dening therewith an evacuatable space;

(c) a radiation shield around said inner vessel within said evacuatable space and attached to said neck of said inner vessel through -connector means;

(d) vapor coolant tubing means adapted to withdraw cold vapor from within said inner vessel and to cool in order, through out-of-contact heat exchange, said neck near its juncture with said inner Vessel, said radiation shield, and the upper portion of said neck enclosed within said outer vessel;

(e) insulation wrapped around the outside of said radiation shield;

(f) a lateral support system formed of 1) a bottom lateral support comprising (i) a vertically disposed stud affixed to the bottom of said inner vessel and having depending therefrom at least three equally spaced extensions forming curved contacting inner vessel lands,

(ii) a sheath surrounding the bottom portion of said stud, affixed to said radiation shield and having on its internal walls at least three curved and equally spaced contacting lands in the same plane -as said inner vessel lands and alternating in position with said inner vessel lands,

(iii) a spacer body of low thermal conductivity positioned to contact the surface of said lands, whereby said inner vessel and said radiation shield are maintained in relative alignment, `and 10 (iv) at least three, low thermal conductivity bands equally spaced connecting said sheath and the internal wall of said outer vessel; and (2) a top lateral support comprising at least three, low thermal conductivity bands equally spaced connecting .said connector means :and the internal wall of said outer vessel;

(g) a rst capillary tubing in Huid communication with the bottom level of the cryogenic liquid in said inner vessel and extending externally of said storage vessel;

(h) a second capillary tubing in fluid communication with the internal volume of said inner vessel :above the upper level of said cryogenic liquid and extending externally of said storage vessel; and

(i) instrumentation and connecting assembly means adapted to form a fluid-tight seal with the upper `opening `of said neck of said inner vessel and arranged to provide fluid connections between external conduits and said inner vessel, and fluid connections for said vapor coolant tubing, said tirst capillary tubing and said second capillary tubing.

14. A cryogenic Iliquid storage Vessel in accordance with claim 13 wherein said fluid connection for said vapor coolant tubing comprises a T-connecting means in fluid communication with valve-controlled first and second alternative fluid paths; said rst Huid path including a fluid ow meter and a muliler adapted for use when liquefaction of said cryogenic liquid takes place within said inner vessel; and said second flow path including one-way uid ow control means and a relief valve.

15. A cryogenic liquid storage vessel in accordance with claim 13 wherein said fluid connections for said first and second capillary tubes terminate in a pressure differential measuring means, Ithereby providing through suitably calibrated gage an indication of the level of said liquid in said inner vessel.

References Cited by the Examiner UNITED STATES PATENTS 2,528,780 11/ 1950 Preston 62-50 2,951,348 9/1960 Loveday et al. 62-50 3,133,422 5/ 1964 Paivanas et al. 62-50 3,134,237 5/ 1964 Canty et al. 62-50 FOREIGN PATENTS 662,356 4/1963 Canada. 662,411 4/ 1963 Canada.

LLOYD L. KING, Primary Examiner.

Claims

1. IN A CRYOGENIC LIQUID STORAGE VESSEL FORMED OF AN INNER VESSEL HAVING A NECK SECTION, AN OUTER VESSEL AND AN EVACUATED SPACE THEREBETWEEN IN WHICH IS LOCATED RADIATION SHIELD MEANS, A LATERAL SUPPORT SYSTEM FORMED OF (A) A BOTTOM LATERAL SUPPORT COMPRISING IN COMBINATION (1) A VERTICALLY DISPOSED STUD AFFIXED TO THE BOTTOM OF SAID INNER VESSEL AND HAVING DEPENDING THEREFROM AT LEAST THREE EQUALLY SPACED EXTENSIONS FORMING CURVED CONTACTING INNER VESSEL LANDS, (2) A SHEATH SURROUNDING THE BOTTOM PORTION OF SAID STUD, AFFIXED TO SAID RADIATION SHIELD AND HAVING ON ITS INTERNAL WALLS AT LEAST THREE CURVED AND EQUALLY SPACED CONTACTING LANDS IN THE SAME PLANE AS SAID INNER VESSEL LANDS AND ALTERNATING IN POSITION WITH SAID INNER VESSEL LANDS, (3) A SPACER BODY OF LOW THERMAL CONDUCTIVITY POSITIONED TO CONTACT THE SURFACE OF SAID LANDS, WHEREBY SAID INNER VESSEL AND SAID RADIATION SHIELD ARE MAINTAINED IN RELATIVE ALIGNMENT, AND (4) AT LEAST THEEE, LOW THERMAL CONDUCTIVITY BANDS EQUALLY SPACED CONNECTING SAID SHEATH AND THE INTERNAL WALL OF SAID OUTER VESSEL; AND (B) A TOP LATERAL SUPPORT, COMPRISING IN COMBINATION (1) CONNECTOR MEANS JOINING SAID RADIATION SHIELD MEANS WITH SAID NECK SECTION OF SAID INNER VESSEL, AND (2) AT LEAST THREE, LOW THERMAL CONDUCTIVITY BANDS EQUALLY SPACED CONNECTING SAID CONNECTOR MEANS AND THE INTERNAL WALL OF SAID OUTER VESSEL.