DE2150866A1 - Container for storing and / or transporting cryogenic liquids - Google Patents

Abstract

1300730 Cold liquefied gas storage tanks CONCH INTERNATIONAL METHANE Ltd 23 Aug 1971 [14 Oct 1970] 48749/70 Addition to 1203496 Heading F4P In a cold liquefied gas, e.g. methane storage tank as claimed in parent Specification 1,203,496 wherein the tank 4 is surrounded by heat insulation material 7 lining the inner face of an outer rigid shell 2, e.g. the inner hull of a ship and wherein the upper less stressed portion B of the heat insulation material is of foamed plastics material, e.g. polyurethane sprayed in situ on the inner face of shell 2 whilst the lower more highly stressed portion C of the insulation is of load bearing material, the latter comprises members C1, e.g. of balsa wood faced with plywood rigidly fixed to and spaced over the shell bottom with the intervening spaces C 2 filled with sprayed-on rigid foam plastics material; the junction planes between C1 and C2 being inclined to the shell bottom. As shown tank 4 rests on pinewood blocks 17 supported by insulation members C1. The insulation material B at each side of the shell 2 which is chamfered is of nylon mesh and polyurethane except at the corners D where the insulation comprises balsa panels held by wood strips 9. The top insulation A comprises fibreglass 21 faced with plywood 22. The tank has ribs 5, a bulkhead 6 and keyforming brackets 18, 19 at opposite sides of blocks 17.

Description

DR.ING. F.WtTESTHOFF 8 MtTNCHEN 9O DIPL. ING. G. PITLSf SCHWEIGEHSTHASSE 2 DR.E.T.PBOHMANN timio »(0811) 66 20 si DH. ING. D. BEHRENS τει, εχ 5 24 070 DIPL. ING. R. GOETZ thlkohammk: PATENT LAWYERS r \ Λ Γ Π OCC

1A-40 226

Description 25U of the patent application

COUGH INTERITATIOIiAL METHANE LIMITED, Nassau, The Bahamas

concerning

Containers for storing and / or transporting t £ g: f-cold liquids

(Addition to patent application P 19 09 693.6)

The invention relates to containers for laying and / or transporting liquids at temperatures which differ significantly from the ambient temperature, and it relates to a development of the invention according to the Patent (patent application P 19 09 693.6), which

deals with the thermal insulation of such containers

According to the main patent, a container of the type mentioned is characterized in that less highly stressed parts The thermal insulation can comprise a rigid foamed plastic material that is in place on the inside a rigid outer jacket is sprayed on, while more stressed parts of the thermal insulation from a Resilient thermal insulation material of higher strength exist.

In the main patent two embodiments are described, one with reference to FIGS. 1 to 3 of the accompanying drawings, which is a container of the

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deals with a self-supporting tank and a second with Pig. 4, which is a so-called "integrated tank container".

In treating a container of the type with a self-supporting tank, the H & upt patent indicates that the cross-section of the thermal insulation that covers the bottom of the rigid outer jacket and supports the bottom of the T.:nks, consists entirely of a resilient material with high compressive strength. The arrangement described proves to be true as advantageous as it not only forms a second barrier to the liquid in the tank, but also that Weight of the container and the liquid it contains, as well as in the case of a tanker carrying such containers or Tanks is equipped to absorb all the varying loads that occur when loading and unloading the liquid, but In practice, the material costs and the labor costs turn out to be for the assembly of such an insulation section as high when compared with the cost of the foamed insulation sections than that according to FIG in the description given in the main patent, the side walls of the rigid outer jacket are formed.

The present invention is now based on the object of creating a different insulation construction for the insulation section covering the base of the rigid outer kneels in a container of the type with a self-supporting Τεϊύζ, which insulation section is firstly designed so that it adequately supports the base of the table which, secondly, is adapted to act as a second barrier, and thirdly, in which, thirdly, at least partially the thermal insulation arrangement is used which is contained in the H; _{Uptpatent described IsIi 5} with regard to the side walls of the rigid outer jacket, so that corresponding cost savings are ex-given.

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_ 3 -

According to the present invention, includes "in a container for storing and / or transporting liquids at temperatures which differ significantly from the ambient temperature, the container comprising a self-supporting inner container or tank which is supported by a V / arms arranged in a rigid outer cantilever insulation is surrounded, the part of the insulation that forms a cladding of the bottom of the shell carrying the T: .nk, support members made of a resilient thermal insulation material, which are rigidly connected to the bottom of the! .. Tntels and at intervals across the bottom of the ι, -., ntels are distributed, as well as a rigid foamed plastic material, which is injected on the spot into the gaps between the support members, and the planes of the joints or connection points between the support members and the rigid foamed plastic material run obliquely to the plane of the walls of the coat.

Here, each support member preferably comprises a plywood-clad layer of balsa wood panels, which with Plywood clad and rigid with the bottom of the jar are connected.

Appropriately, a load-bearing block is attached to the top of each layer of panels, which is suitable to support the tank at a distance from the rigid foamed plastic material.

Alternatively, each resilient log comprises a second layer of balsa wood panels, and the top of that second The layer can be provided with a layer that ensures good friction-locking contact with the bottom of the tank

In the case of a tanker, the floor may be suitable for use be provided with a guide arrangement comprising two rows of abutments, the distance between the both rows on the one hand and the rows of support members

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21büöüb

is chosen so that an Ecihe of abutments with a None of the support members work together to determine the location of the tank when the temperature is up to the ambient temperature is located, and the other set of abutments cooperates in a similar "manner with the series of support members, if the dimensions of the tank have changed because the ΐε-nk assumes the temperature of the liquid cargo Has.

The invention and advantageous details of the invention are described below with the aid of schematic drawings explained in more detail using exemplary embodiments.

1 shows half of a tanker in a vertical cross section.

2 is an enlarged section from FIG. 1, the more details of a lower section of the heat isolation shows.

J shows in an enlarged partial section a modified embodiment of the Pig detail. 2.

Pig. 4 shows, in part of a plan view, a floor section of the thermal insulation.

According to Pig. 1, the tanker comprises an outer hull 1 and an inner hull 2. The inner hull 2, together with two transverse bulkheads, not shown, forms a hold $. The tanker can be provided with several such holds. In the hold 3 is a self-supporting T; nk 4 is provided, which consists of a metal that is not exposed to cold embrittlement at the temperature of liquefied natural gas; For example, the tank is made of aluminum or steel with a c Hittelgehalt of ψ ο}. The tank 4 has a sufficient wall thickness and is supported by internal Kiüuaenglieder, one of which

098 28/0 496 BADORiGiNAL

is shown at 5, stiffened so that it can hold the liquid cargo together can also be a bulkhead 6 is provided in the tank, which extends along the central axis of the tank. The tank 4 is surrounded by a total of 7 *> ^e drawn thermal insulation, with which the cargo space 3 is lined. i'ig. 1 is not drawn to scale, and in particular, for the sake of clarity, the thermal insulation is shown on a larger scale than the tank ship,

The thermal insulation 7 comprises a section A which forms a cladding of the upper side of the cargo space 3 and each extends a short distance down to the side walls of the hold, furthermore sections B, form the cladding of the side walls of the cargo space, as well as a section G, which forms a cladding of the floor of the cargo space.

Each of the sections B of the thermal insulation, which are formed essentially in the same way as the section B described in the main patent, comprises a constant thickness layer of rigid, closed-cell polyurethane 8 which is applied in the form of several layers to the main parts of the S ^; . the building of the cargo hold 3 is sprayed on. In contrast to the Luuptpatent, according to which layers or Letten made of burlap are embedded in the polyurethane material, in the present case layers are incorporated into the polyurethane material, which consist of a nylon mesh material or braid.

The i-corners or edges of the cargo space 3 that pass through the Sidewalls are formed, i.e. the top, the bottom and the vertical jackets are with void portions D clad from a resilient V / heat insulation material, which are formed essentially in the same way as the section A after the Ii; uptx> apent; it has been particularly suitable for the df.ß the container is intended for liquefied natural gas,

20 9 8 2 8/0 A 96 BAD original

has shown that the temperature gradient at the insulation, which is in the order of magnitude of 160 ° O when liquefied natural gas is under normal atmospheric pressure, leads to critical stresses on the polyurethane material, since this material has a relatively high coefficient of thermal expansion, which according to the Main patent in the range in question of the density values of the polyurethane in the order of 40 to 50 x 10 "" m / m / ⁰ 0. These critical stresses are particularly in the area of the edges of the group consisting of polyurethane portions of importance, and if the corner portions of the loading space of the sprayed layers or preformed I ¹ UIlstücken would consist of this material, as proposed in the main patent, sowieit the vertically extending corners come into consideration, the combined effect of the critical stresses from the adjacent wall sections could lead to the tearing off of the corner sections, that is to say that they are separated from the corners of the hold; to be pulled. In view of this, each corner section D therefore comprises Qiragträger 9 made of wood, which are evenly spaced over the respective corners of the hold 3, as well as panels 11 made of balsa wood, which are covered with plywood and connected to the support strips 9, for example by an adhesive. In addition, in this construction, the tank 4 is shown in FIG. 1 is provided with a bevel 12 in its lower part, and the outer space 3 is shaped to match this bevel. As a result, the side walls of the loading bay are provided with an obtuse-angled intermediate section to which a further section D is attached. The connections between the sections B and the gap sections D are again essentially designed as described in the main patent, ie the plane of each connection point extends at an angle deviating from a right angle to the plane of the relevant W - nd of the hold, furthermore. are in this

BATH ORIGINAL

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Construct the layers using a nylon mesh material the surface of the corner portions by an adhesive and not connected by means of slots according to the H & upt patent; at each section B the two extend at furthest inner layers made of the ijylon mesh material seamlessly over all parts of the section in question, while the two outermost layers extend from each corner section D extend into the polyurethane material only over a relatively short distance.

According to the definition, the section C is provided with a combined insulation, which consists of polyurethane and resilient parts, the resilient insulating parts locally limited i'lacfrf η to support the bottom of the -i'L.nks 4 and not about Form a complete support., -as it is provided according to the main patent for the part of the insulation designated with A. Section C of the insulation generally comprises a combination of the insulation of section B and the resilient insulation construction of corner sections U, both of which are described above. According to JTig. 2 extend through separate distances borrow from beleistbaren insulation sections 01 parallel to the longitudinal axis desu.cnksch.iffs, and they are at the _o B to the loading space 5 secured. As mentioned, these Hc-ihen of insulation sections are designed similarly to the corner sections I), and they comprise layers of balsa wood panels 13, which are clad with plywood 13A, the longitudinal edges of the leads each at an acute angle to the plane of the Li. the room floor extend. It should be noted, however, that the maximum strength of the sections 01 must be present in the right toinkol to the plane of the lid compartment floor, while the corner sections D are stressed parallel to the planes of the loden and the sides of the cargo hold, and the lr Isaholz parallel to its masuration has a higher strength, the lasering of the balsa wood therefore runs the T. - fine of the "sections 01 at right angles to

20 9 8 2 B / 0 4 9-6

BATH ORIGINAL

Grain of the balsa wood of the corner sections D. Da as well the sections 01 must be able to take a load, no support strips made of wood are provided, and instead are the layers from the panels 13 with the cargo hold floor directly connected by means of screws 14 protruding through counterbores near the inclined edges of the panels 13; the countersunk holes 13B have been filled in after fastening as shown in FIG and covered by the plywood panel 13A. There no If support strips made of wood are provided, the thickness of each of the sections 01 is the thickness of the support strips that have been omitted enlarged. Sections 02 between sections 01 and between the outermost sections 01 and the corner sections D adjacent to them are provided with layers of polyurethane completed in exactly the same way as described above in relation to section B. It should be noted that prop. 2 also shows the described layers of nylon mesh material; the two innermost layers can be seen in FIG Layers 15 and the two outermost layers 16.

Each section 01 forms a rigid and solid SUPPORTING U _n for a resilient pad 17 which, for example of dense hardwood, for example from American spruce wood, is composed, and the bottom of Ί \ nk 4 is supported on the blocks 1? From j the number of sections 01 and the distances between adjacent sections 01 and thus also the blocks 17 relative to the floor of the hold 3 are chosen so that the blocks have sufficient strength to withstand the static load of the oil and the liquefied natural gas contained therein as well as all varying loads that occur when loading and unloading the tanker. Should it be necessary to reinforce the blocks 17 so that they can withstand shear stresses during Schlingerbewegungeη the tanker, the blocks can be provided with horizontal and / or vertical layers made of plywood, for example. According to FIG. 2, a section 01 is arranged coaxially with the central longitudinal bulkhead 6 of the Tf nks 4, and

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all other sections G1 are preferably in longitudinal alignment with a floor reinforcement member 5 extending in the longitudinal direction for the tank 4 »

The Köötze 17, which carry the tank 4, can also serve to keep the tank in a predetermined Lt.ge. For this purpose, two sets of abutments 18 and 19 are provided which are fixed to the bottom of the tank 4 and arranged so that when the tank is at ambient temperature, the abutments 18 cooperate with the side surfaces of the blocks 17 which the Longitudinal axis of the tank are facing in order to (hold the tank in its position) when the tank has cooled down while being filled with liquefied natural gas, the other abutments 19 cooperate with the surfaces of the blocks 17 facing in the opposite direction. In this latter state The tank 4 will have contracted under the effect of the cold of the liquefied natural gas in the direction of its central plane, and therefore when fitting the abutments 19 under ambient conditions it is necessary to provide sufficient distances between the abutments and the surfaces of the blocks 17 adjacent to them, in order to take this thermal jxont «bction into account. According to a further development of the invention, to 19 change the spacing of the abutments such that when the tanker at sea rolling movements out, the load of those abutments 19 and pads is taken up 17 in each moment at least the major part, which on the one: are ¹ side of the Litielebenedes Tcnks facing away from the side towards which the tanker is heeled} this offers the advantage that the effective gradient of the liquefied id ^ ases and, thus, the load on the named side of the middle level of the tank is considerable becomes less than on the other side.

Fi {- ,. 't> shows a modified embodiment of the invention, in which the sections 01 of the thermal insulation comprise layers of BaIsaliol ζ panels 15, which are made with plywood

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13A and in a manner similar to that described above with respect to the corner portions D, are attached to spaced-apart support strips 21 made of wood. To ^; However, to reinforce the sections 01 and to ensure that they have sufficient strength to withstand the static and the varying loads from the Tsnk 4, a second layer of BaIsahoiztafein 22 is attached to each layer of T. adjacent support strips 21 is arranged. This second layer of panels 22 has a smaller thickness than the support strips 21 in order to compensate for irregularities in the floor of the loading space 3, and the gaps that remain between the layer of panels 22, the loading space 3 and the support strips 21 are covered with a resilient putty 23 completed. In addition, in this modified arrangement, the resilient blocks 17 for supporting the bottom of the tank 4 comprise a third layer of balsa wood panels 24, the ag. 13% of the layer of panels 13 is attached to the plywood cladding. The layer formed by the panels 24 is also provided with a cladding 25 made of plywood in order to ensure a good xie ibigschlüssige contact between the sections 01 and the bottom of the tank 4 when the ΐε-nk is filled with liquefied natural gas, so that a less likely that the Ti.nk tends to shift during loading and unloading; As a result, the expected load on the abutments 18 and 19 is reduced.

KLg. 4 shows a typical arrangement of the thermal insulation 01 and 02 on the floor of the cargo hold 3. In this arrangement, a series of mutually abutting sections 26, which correspond to the sections 01, extends along the longitudinal median plane of the cargo hold floor of the T; nkships. In addition, heights of sections 2 ^r / corresponding to sections 01 are arranged on both sides of the lu ihe of sections 26 at a distance therefrom and in parallel therewith; here

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each row 27 comprises several separated by longitudinal distances island-like sections, so that a plurality of separate support surfaces is distributed over the bottom of the tank 4-. As mentioned, the number, the spacing and the area of the none of 01-sections 26 and 27 are chosen so that aer Te.nk 4- against all expected dormant and varying The stresses to which the Tcnk is exposed during loading and unloading is adequately supported. Furthermore, the Arrangement according to Fig. 4- the iteihe of sections 26 with a Keyway 26 is provided, which extends along the longitudinal plane of the tanker extends and a tidl, not shown receives the one on the underside of the bottom of the T; nks 4- provided is. Such a sub-arrangement forms an alternative to the arrangement described above with reference to "FIG. 2" with the abutments 18 and 19, and it is similar to the arrangement described in patent specification 1,121,960. G-eiaäß According to this patent specification, the basins of the T. nks 4- can be stabilized against the leaks of the tanker in order to avoid the risk of danger to reduce that the tank on the sections 01 of thermal insulation Performs rocking movements.

Tests have shown that a thermal insulation arrangement of the type described above for the side walls and the floor of the hold 5 impermeable to liquefied natural gas is, and that it would therefore form a second barrier to the liquefied natural gas if the tank 4 ripped open should. In particular, experiments on egg & er in natural The size of the connection point between a resilient insulation and the polyurethane material, which are formed essentially as described above was; these tests were carried out at normal operating temperature and under varying load conditions ü carried out, wobc-i the stresses by a 'multiple were higher than those during normal operation of a Ti.nksch.schiff stresses to be expected on the high seas; here resulted There are no signs of the tank tearing open.

209828 / CH96 ^ ₀ ORIGINAL

The spaces between the side walls and the bottom of the tank on the one hand and the hold on the other hand can also be at least partially filled with an additional, relatively cheap thermal insulation material, for example a fiberglass material. When such a glass fiber material is provided in the trees between the side walls of the ^r ücnks and the loading space, this material can be arranged to the description in the main patent on the respective surface of the insulation assembly or on the outer surface of the QJanks invention. In both cases, a load-bearing structure, not shown, can be used to hold the fiberglass in place.

The location of the section A of the thermal insulation is such that it is not important that it is suitable as second lock to come into effect, but it should be impermeable to splashed liquid. Thus, in This FfOLl provide a relatively inexpensive thermal insulation made of a fiberglass material clad with plywood 22 21 exists.

Expectations:

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Claims (1)

EXPECTATIONS Iy containers for storing and / or transporting Liquids at temperatures that rise ch of the Ambient temperature differentiate with a tank enclosed in a rigid outer jacket by thermal insulation the part of the thermal insulation covering the loden of the skirt supports the drink, characterized in that the part supporting the tank Part (C) of the thermal insulation support members (G1) from a resilient Thermal insulation material includes that with the floor of the I.I & ntels (3) rigidly connected and spaced over the Soil are distributed, that said part is also a starx'ea Foamed Jüunststoffmaterial (G2) comprises that in place and Place injected into the spaces between the support members has been, and that the joints or junctions between the trot members on the one hand and the rigid foamed Plastic material on the other hand obliquely to the Kbonen the Walls of the lintel run down. 2. Container according to claim 1, characterized in that g e k e η η draw t that each support member (G1) comprises a layer (12) of Bolsa wood panels which are clad with plywood (13A) unu is rigidly connected to the bottom of the lintel (ρ). i>. A container according to claim 2, characterized in that a resilient block (T?) Is attached to the top of each layer (13) of BaIsahoiztafein which supports the tank (4) at a distance from the rigid foamed plastic material (C2). 209828/0496 ' 4. Container after. Claim. 3 »characterized in that each loadable block (17) has a second Layer (24) of beisaholztafein comprises. $. Container according to claim 4, characterized in that the second layer (24) consists of Lelsa wood panels on their top with a cladding (25) is provided, which has a good frictional contact with the bottom of the tank (4) ensured. 6. Container according to one of claims 2 to 5 »characterized in that each first layer (13) made of Balsaliolztai'eln is connected to the Loden des ^ antels (3) by spaced strips, strips (21) made of wood, and that a third layer (22) of B; .Isaholzafeln attached to the underside of the first layer and embedded in a putty (23) in the nLun between adjacent support strips. 7. Container according to one of claims 1 to 6, characterized in that the l'ragglieaer (C1) over the ioden of the lintels (3) in the form of separated by gaps Ii, ihen (27) are distributed, 8. A container according to claim 7> characterized in that the bottom of the T-.nks (4) has a wedging sanordnung comprising two sets of longitudinal straight lines arranged abutments (18, 19), and that the distances between the legs of abutments and along a straight line "arranged -Tiiaggliedern (G1) in such a manner are _r - .. that a S tz of abutments with the Tia _t cooperating members, in order to keep the tank in its position when the tank befinaet on the ambient temperature, and the second set of abutments works in a similar way with the TroLglieaem when the dimensions of the tank have changed. 209828/04 96 9. A container according to claim 7 »characterized in that a number of ^r i: rag links (26) extends seamlessly along the longitudinal center line of the Loden desx-antels (5) that the other iteihen (27) of support members run parallel to this longitudinal center line and are arranged at a distance therefrom, and in that they comprise island-like sections (01) which are distributed longitudinally at intervals and which form a multiplicity of separate pools for supporting the loden of the i'cnks (4). 10. A container according to claim 9 »characterized in that the longitudinal center line of the ü \ '.. nks (4) extending Ht.ihe of l'rag members (26) has a longitudinally extending central wedge or jjühj ⁱ unc ; has snut (28) which is suitable for receiving a matching wedge or LiIteleiste provided on the loden of the inside (4). 2 0 9 8 2 8/0496 BAD CNRlGlNAL Blank page