KR20070001996A - Support assemblies and systems for semi-membrane tanks - Google Patents

Abstract

Support assemblies (1) for attaching the walls and top of a semi-membrane tank to surrounding support structure include interlocked angled sliding surfaces, where movement perpendicular to the walls and the top is permitted as well as movement along one line or two perpendicular lines parallel to the tank sides and top. Arrayed on the surfaces of the walls and tops, these support assemblies provide the necessary support for the tank walls and top while minimizing thermal stresses in the tank. Support systems comprising such arrays, surrounding support structure, and tank insulation can be assembled outside a ship and engagingly lowered into a compartment therein, facilitation construction. ® KIPO & WIPO 2007

Description

SUPPORT ASSEMBLIES AND SYSTEMS FOR SEMI-MEMBRANE TANKS

The present invention relates to liquids that can be stored and transported at temperatures substantially lower than room temperature, in particular to storing and transporting liquids such as liquefied natural gas (LNG), liquefied petroleum gas and anhydrous ammonia at temperatures substantially different from room temperature. A system for supporting the side walls and the top of a semi-membrane tank used for this purpose. The invention also applies to semi-membrane tanks for the reception of liquids stored and transported at temperatures substantially above room temperature.

Semi-membrane tanks are not self-supporting. The side walls require support from the peripheral support structure. Although flat structures with relatively light rigid members can also be used for semi-membrane tanks, US Pat. No. 5,727,492 describes a semi-membrane tank having sidewalls of a curved plate structure. As described in US Pat. No. 5,727,492, the peripheral support structure may include, for example, the inner hull of a beam grid or double hull tanker supporting a storage tank in a land based installation. The semi-membrane tank side and top are connected to the peripheral support structure via an adiabatic support or support assembly.

The bottom part of the semi-membrane tank has a flat structure and is placed on the load bearing insulation, which is in turn placed on the lower support structure. The tank bottom and the load bearing insulation may be flat, such as in one horizontal plane parallel to the lower support structure, or in a number of sloped planes oriented towards the anchor point to facilitate drainage. Typically, the tank bottom portion contracts and expands around the anchor point, which is usually disposed either at its geometric center or at another point vertically aligned with the expansion dome on the top of the tank. This anchor point is typically held in a fixed position by a combination of structural keys secured to the outer surface of the tank bottom. The key extends radially from the fixation point, and typically mates with the key-way of the load bearing insulation oriented normal along the transverse and longitudinal axes of the tank. With the change in temperature when the tank is filled and emptied, the tank bottom part contracts and expands by gravity, sliding over the load bearing insulation that the tank bottom part is held against.

The temperature of the side wall of the tank and of the tank upper end also deviates significantly from the normal room temperature of the peripheral support structure when the tank is filled. This thermal deviation tends to cause shrinkage when the tank is used for cold liquid and cause the tank to undergo significant thermal stress. The support method between the tank and the peripheral support has a significant effect on the distribution and level of these thermal stresses.

The thermal insulation system is typically fixed directly to the tank surface after the tank structure is substantially finished. Insulated support systems for semi-membrane tanks are typically attached directly to the peripheral support structure, which, in the case of linear installations, is to be formed integrally with the longitudinal and transverse structures.

Published US Patent Application Publication No. 2003 / 0066834A1 discloses an array of support assemblies for use in a support for a semi-membrane tank. The assembly is a component interposed between the peripheral support structure and the tank wall. The assembly of this published patent application comprises three components or blocks, the first block rigidly attached to the tank wall, the second block rigidly attached to the peripheral support structure and the two blocks interposed therebetween. Is a third block. The third block slidably engages with the first block to allow sliding movement along a first line parallel to the plane of the tank wall, and the third block slidably engages with the second block, again of the tank wall. Allows sliding movement along a second line perpendicular to the first line, parallel to the plane. In combination, the two slide movements enable orthogonal movement of the tank wall in the tank wall plane relative to the support structure. The support system prevents inward and outward movement perpendicular to the side walls and top of the tank.

When considering a rectangular tank with four sidewalls, top and bottom, it can be seen that the unregulated thermal shrinkage resulting from the lowered temperature causes each of these six members to shrink in its plane. As a result, the tank becomes smaller by pulling inwardly in a direction away from the peripheral support structure to which the tank is attached by the support system. The wall of the semi-membrane tank should have at least a fixed point aligned with a fixed expansion dome protruding through the upper end. In addition, the non-independent walls and tops must be supported vertically, and the walls must also be supported vertically to their respective planes. As an example, the support system of US Patent Publication 2003/0066834 A1 only permits contraction in the plane of each wall and prevents inward movement in a direction away from the support structure. The particular support assembly is fixed with respect to the vertical movement of the wall and thus supports the tank wall. The regulation of the motion perpendicular to the plane of each wall imparts significant thermal stress at the edge where the tank wall encounters the top, bottom or other wall. Thus, these intersections must be sufficiently rigid to provide acceptable stress levels to the tank structural material while being flexible enough to accommodate shrinkage. Flexibility is typically achieved by using edges with a significantly curved cross-sectional shape that can accommodate significant distortion as the tank shrinks. The radius of curvature must be large enough to allow this distortion without reaching unacceptable stress. In order to prevent buckling and maintain acceptable stress levels under all temperature conditions caused by a full, empty or partially filled tank, the thickness of the structural material of the bent edges must be thick and strong enough. Small radius curved edges of relatively light structures are not suitable for this purpose because of the magnitude of the stress level.

The object of the present invention is to provide support for semi-membrane tank walls and tops that provide thermally structural attachment between the tank and its surrounding support structure, which overcomes the disadvantages of existing arrangements and improves the efficiency of constructing and installing such tanks. To provide an array.

One aspect of the present invention allows a wall or top of a semi-membrane tank to reciprocate vertically in the plane of the wall or top, while at the same time a vertical line in or in a line in the plane of the wall or top To support the contraction and expansion of the wall or top of the wall.

The deployment of the support assembly according to the invention in an array across a semi-membrane tank wall minimizes the heat induced stress at the edge formed by the intersection of one wall with a top, bottom or other wall, Provide support for the walls comprising the required vertical support.

Another aspect of the present invention allows to increase the tank volume while simultaneously reducing the radius of curvature of the tank edges as compared to the existing system described above, and also to reduce the amount of tank structural material, thereby providing a configuration. Arrays of support assemblies that simplify and reduce construction costs.

Another aspect of the invention is the use of a support assembly for securing a panel or sheet of tank insulation in place, for example, to a support assembly to which the insulation panel is fixed to minimize heat transfer to the tank. Use of a flanged device to secure the support assembly to the tank in combination with a flanged collar.

Another aspect of the invention is a wall of a semi-membrane tank and, optionally, a support system for the tank bottom, which includes the perimeter support structure and the perimeter support structure on the inner hull of the tank or on the outside of a coastal installation built on site. Means for slidably coupling an outer containment structure, such as a frame, for example a vertical key to a tank support system for a wall, in which the key slidably engages a keyway attached to a surrounding vessel structure. It includes an attachment portion. This aspect simplifies tank installation by securing the tank wall and bottom to, for example, the peripheral vessel structure by the simple act of engaging the key and the keyway when the peripheral support structure containing the tank is lowered into the hull of the vessel. do. In a preferred embodiment the key and keyway are preferably tapered in cross section and vertically to facilitate engagement when the tank and the peripheral support structure are lowered into the surrounding vessel or coastal base structure. .

It is a feature of the present invention that the walls and the top end allow relatively minor deviations from the low temperature plane.

In the present application and the appended claims, certain terms have the following meanings:

"Wall" means the vertical sidewall of the semi-membrane tank. The walls of the semi-membrane tanks are arranged in geometric patterns, for example rectangular, trapezoidal, hexagonal or cylindrical tanks. The walls of such tanks are planar when made of flat plates and almost planar when made of curved plates. Such walls are variously referred to herein as "flat" or "planar." The cylindrical tank has one continuous wall forming a cylinder.

By "plane of walls" is meant a vertical plane connected to a major planar outer surface at room temperature in a straight-sided wall of a plate structure, or a plate that is curved through a cusp in such a wall.

"Plane of the upper end" means the main planar outer surface of the tank upper end at room temperature.

"Peripheral support structure" is a structure to which the support assembly is attached in a direction away from the tank. The peripheral support structure may or may not be integral with an outer containment structure, such as a peripheral ship structure. Alternatively, the peripheral support structure may be a lifting frame, a frame in which the tank is assembled. The peripheral support structure may be installed with a vertical key that engages a keyway integral with the outer containment structure when the tank is lowered to its final position, and vice versa.

An “outer containment structure” is a structure outside the peripheral support structure when they are one and not identical. For the wall of the tanker installation, this is the internal longitudinal hull structure and transverse hull bulkhead structure comprising a bracing member attached thereto, and for the upper end it is generally the main deck of the double hull tanker. to be. The outer containment structure for the walls of a coastal installation is typically a frame of interconnected beams extending upward from the ground concrete base.

"Ramp" means an angled surface projecting outward from a tank slidably engaging a complementary surface supported by a peripheral support structure. This surface may be planar or have a curvature of 1 degree with the axis of the surface parallel to the angle of the inclined portion. Movement along the slope means movement up and down the slope parallel to the axial centerline of the slope. "Across the slope" and "cross the slope" movement is a movement parallel to the inclined plane, but if the inclined plane is flat, the movement in the direction perpendicular to the axial centerline of the inclined plane or, if the surface is curved, the chord of the arc of the surface Means parallel movement. The inclined upward or downward movement can be divided into two vertical components of the rectangular coordinate, for example, components along the x axis and components along the y axis. When the inclined portion is disposed horizontally on the vertical surface, one moving component parallel to the inclined portion is horizontal and parallel to the plane of the wall and the other component is also horizontal but perpendicular to the plane of the wall; The movement across the slope is perpendicular and parallel to the plane of the wall. When the inclined portion is disposed vertically on the vertical surface, one moving component parallel to the inclined portion is vertical, parallel to the axis of the cylinder when the plane of the wall or the tank is cylindrical, while the other component is horizontal , The plane of the wall or perpendicular to the axis of the cylinder, the movement across the slope is horizontal and parallel to the plane of the wall or the wall of the cylinder.

By "sloped in a direction away from a point or line in a tank wall or top part" is meant a support assembly in which a member attached to the tank wall or top part has an inclined angle at an acute angle towards this point or line.

“Support assembly” means a collection of spaced interlocked structural components or members between a peripheral support structure and a tank wall or top portion that together enable attachment of a wall or top portion to the peripheral support assembly.

The support assembly according to the invention is inwardly directed in at least two directions, in one direction perpendicular to the axis of the cylinder of the wall or the top or the cylindrical wall of the wall, ie away from the support structure when the tank contracts, Outwardly directed toward the support structure when the tank is inflated; And at least one direction parallel to the axis of the cylinder of the cylindrical wall or parallel to the plane of the wall or top, that is, towards the anchor point or line in the plane of the wall or top or when the wall or top contracts. Toward and away from this point as the tank expands, allowing the tank wall or upper end to move relative to the peripheral support structure. Movement in two directions is achieved by an "two-dimensional" support assembly angled with respect to these two directions while allowing movement along the slope. When the wall or top portion contracts in the plane of the wall or top portion, or when the cylindrical wall contracts, the incline attached to the wall or top portion translates relative to its complementary surface, thereby towards or against the axis of the cylindrical wall. Or deflect the inclined portion inwardly perpendicular to the plane of the upper end. By setting the inclination angle to an appropriate magnitude, at a point where this is otherwise not the best thermal stress, a suitable inward deflection is obtained to minimize the stress. Thus, the slope near the anchor point, for example the center point of the length of the flat wall, translates at a shorter distance in the plane of the wall, whereby the slope is shorter than that tilted further outward from the anchor point. Deflect at a distance perpendicular to the plane, thereby receiving a greater amount of deflection when the tank is retracted. In this way, when the tank contracts and expands, active inward support of the tank wall or top in the direction away from the surrounding support structure is maintained and at the same time rolling or pitching or liquid cargo of the vessel at all temperatures ( Mechanical forces such as the pressure of the cargo prevent the tank wall or upper end from moving outwards. The calculation of the inclination angle is a matter of design based on the thermal characteristics of the wall or top and the defined tank shape, which is within the current state of the art. The horizontally arranged two-dimensional support assembly provides a vertical support for the tank wall.

Another support assembly according to the invention further permits movement in the plane of the wall or upper end perpendicular to the first direction. These assemblies thus allow orthogonal movement in the plane of the wall or top and movement perpendicular to the plane of the wall or top. Additional degrees of freedom of movement are provided by the "three-dimensional" support assembly.

The support assembly according to the invention can be included in an array of supports between the peripheral support structure and the tank wall or top. Each array for a planar wall or top includes a "center of thermal fixity" which is either a point with no thermal movement or a rigid attachment point. The thermal anchoring center for each of these walls is at a common height above the bottom of the tank and is aligned horizontally with the fixed point of the upper end determined by the expansion dome, ie the center point of the dome. Each planar wall array further includes a row of support assemblies extending in both directions in a direction away from the thermal fixation center in the horizontal direction. Each of the support assemblies in this row is a two-dimensional support assembly that allows movement only along the inclined portion, and the inclined member is rigidly attached to the tank having the inclined surface oriented in a direction away from the fixed point in the horizontal direction. That is, the inclined upward movement is a movement away from the thermal fixation center. Each of the support assemblies in this row provides a vertical support for the tank wall since the vertical movement of the wall relative to the support structure is not allowed. Each array for a cylindrical wall includes a number of thermal fixation points that are preferably disposed at or near the bottom of the wall. Each array for a cylindrical wall comprises a plurality of two-dimensional and three-dimensional support assemblies disposed vertically in a predetermined pattern, along a series of vertical lines disposed over the surface of the wall, preferably around the wall.

In addition, each array for the planar wall or top includes an additional support assembly according to the invention. These additional assemblies may be two-dimensional support assemblies or three-dimensional support assemblies, where inclined portions are oriented radially away from the thermal fixation center, and in the case of three-dimensional support assemblies, the inclined portions are horizontal rows. And oriented in a direction away from the vertical line through the thermal fixation center in the horizontal direction. Similar arrays can be used for the tank top.

The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.

1 is an exploded perspective view of a two member embodiment of a two dimensional support assembly according to the present invention.

2 is a perspective view of a two member embodiment of a two dimensional support assembly according to the present invention.

3 is an exploded perspective view of a three member embodiment of a three-dimensional support assembly according to the present invention.

4 is an elevation view showing a preferred embodiment for the interlocking attachment of either the three-dimensional support assembly or the two-dimensional support assembly to the tank wall or top and the peripheral support structure, and also flanged fixed to the support assembly. A means for securing a thermal insulation panel installed between a collar and a flange holding a support assembly with respect to a tank;

5 is a side view of a first embodiment of an array of support assemblies according to the invention, a semi-membrane tank, a peripheral support structure.

6 is a side view of a second embodiment of an array of support assemblies according to the invention, a semi-membrane tank, a peripheral support structure.

FIG. 7 is a top view of a semi-membrane tank, peripheral support structure, showing an embodiment comprising a radial arrangement of a support assembly for the top of the tank. FIG.

8 is a top view of a wall assembly showing a preferred embodiment for a peripheral support structure attached to an outer member of a plurality of aligned support assemblies, and also coupled with a vertical keyway integrated with an outer containment structure such as a ship structure. Further illustrating a vertical key attached to a peripheral support structure for the side wall.

9 is an elevation view illustrating another embodiment for interlocking attachment of either a two-dimensional support assembly or a three-dimensional support assembly to a tank wall or top and a peripheral support structure.

Like reference symbols in the various drawings indicate like elements.

The support system according to the invention is distributed over an array of support assemblies, preferably the top and each sidewall, and connects each wall or top with respect to the peripheral support structure by sliding engagement, so that the tank is heated from the temperature heated to the hot tank. When cooled to room temperature or for a cold tank such as an LNG tank, when cooled from room temperature to below room temperature, each point of this engagement of the assembly member attached to the wall or top is inwardly perpendicular to the plane of the wall or top, and, And a two member support assembly that allows movement towards a thermal fixation point in the plane of the wall or top portion. This array may include a fixed support such that each wall or top is rigidly attached to the peripheral support structure, but this is not required. Depending on the design of the array and the orientation of the support assembly, the particular assembly accommodates either one or two degrees of freedom parallel to the plane of the wall or top to allow for the required movement. At least a portion of the support assembly, which only needs to be accommodated to provide this degree of freedom, provides the necessary vertical support for each wall. The upper end of the semi-membrane tank most commonly has a thermal fixation center at the geometric center of the upper end, where the expansion dome penetrates the tank.

1 shows a support assembly 1 according to the invention. The support assembly 1 is a two-dimensional support. This support assembly simultaneously maintains rigid support between the tank wall or the upper end, while allowing thermally induced movement of the wall relative to the peripheral support structure along only the inclined portion, the movement being carried out by the tank wall or A component of the movement perpendicular to the plane of the upper end and a component of the movement along the line in the plane of the tank wall or the upper end parallel to the axis of the inclined portion. The support assembly 1 is shown exploded. It comprises a first member 2 and a second member 3, which can be slidably coupled. One of the members 2, 3 is fixedly attachable to the tank wall or top structure 7, and the other of the members 2, 3 is fixedly attachable to the peripheral support structure 8. The attachment can be made directly or indirectly via load bearing insulation.

The member 2 is a three-dimensional elongated solid T-piece, wherein the upper portion 4 of the elongated “T” is inclined outward from the element 8 as shown, or alternatively, the element It is inclined outward from (7) (not shown). The elongate portion 4 comprises inclined surfaces 5, 6. The member 3 is a solid piece that is complementary to the member 2. It comprises an inclined outward from the element 7 as shown, or alternatively, an inclined outward (not shown), elongated T-shaped inclined recess 9 from the element 8. The recess 9 has a bottom 11 slidably engages with the surface 6 and an upper surface 10 slidably engages with the surface 5 of the member 2, whereby a portion 4 is provided. Can move along the inclined portion inside the recess 9. The recess 9 has an elongate side wall 12 that slidably engages the elongate side wall 13 of the portion 4.

The member 3 surrounds a part 4 of the member 2. The side wall 12 of the member 3 prevents movement across the inclined portion. The bottom face 11 interlocks with the bottom face 6 and is relative to the members 2, 3 perpendicular to the inclination, ie perpendicular to the plane of the tank wall or top, except when caused by sliding along the incline. Prevent exercise.

Other means for interlocking the members 2, 3 can be used to prevent separation of the members perpendicular to the inclined portion. Preferred interlocking means as shown in FIG. 1 directly interlock members 2, 3. Other such means include, by way of example, a T-shaped inclined portion not only for the member 2 but also for the member 3, and the flange and member of the member 2 and the flange projecting outwardly from each inclined element 4. And a slidable U-shaped member interlocking the flanges of (3). Less preferred interlocking means, for example, retain the members 2, 3 together, but do not pivot around the support structure and wall as necessary so as not to prevent movement along the slope of the member 3 relative to the member 2. Or between the top structures 7 can only be indirectly connected to the members 2, 3, such as an angled tie bar pivotally fixed thereto. When the U-shaped additional member is in place, or when the tie bar or other indirectly connected additional member is in place, the members 2, 3 are effectively interlocked.

The walls and top of the semi-membrane tank are important to be insulated from the peripheral support structure and any external containment structure to prevent heat flow out of the hot tank or into the cooled tank. The conductive thermal paths are minimized or removed to the extent possible in the preferred embodiment. For this purpose, the support assembly can be made of a heat insulating material, for example wood or wood composite material. The members 2, 3 can be made of a heat insulating material. However, it may be advantageous for the parts of the members 2, 3, in particular the inclined surfaces 5, 6, 10, 11 to be metals such as aluminum, steel or stainless steel. In practice, it is only important that there is a thermal insulation between the tank and the surrounding support structure to block the thermal path. Alternatively, a thermally conductive material can be used without compromising thermal insulation.

2 shows a support assembly 21 according to the invention. The assembly 21 is a two-member, three-dimensional support assembly interlocked. One exception is that the elongated sidewalls 22 do not prevent movement across the slope, but rather allow recesses in the range calculated as needed by the designer, taking into account thermal shrinkage and expansion of the tank. ) Is configured identically to the support assembly 1 (FIG. 1), and works the same, except that is widened. Thus, orthogonal movement in the plane of the tank wall or top end is accommodated. The embodiment shown in FIG. 2 is, as mentioned, a three-dimensional support assembly consisting of two members. Movement across the inclined portion may also be provided by the third member. Such an assembly according to the invention is shown in FIG. 3. The support assembly 31 further comprises a member 2, 3 as in FIG. 1, except that the member 3 additionally includes a groove 33 and a flange 36 adjacent thereto in a direction away from the inclined surface. And the flange 36 projects oppositely in the direction of the inclined axis. As shown, a third member 34 is rigidly fixed to element 7 or to element 8 (not shown), which bow element 33 comprising flange 36. A spaced inwardly facing tab 35 that creates a transverse slot 37 for receiving into stock. Thus, the member 3 is allowed to move in the member 34 parallel to the plane of the tank wall or the upper end only in the direction transverse to the slope.

The member 3 can be applied to fix the insulation panel in whole or in part on the tank wall. One such application is shown in FIG. 4. FIG. 4 is a cross section through the support assembly 41, which may be either a two-dimensional support assembly or a three-dimensional support assembly as shown in FIG. 2, as shown in FIG. 1. Similarly, a three member three dimensional support assembly (FIG. 3) can replace the two member support assembly 41. The member 2 of the assembly 41 is fixed to the peripheral support structure 8 by, for example, welding or bolting. The base region 42 of the member 3 is shaped to include a flange 43 which projects outwardly parallel to the wall or the upper end 7. A retainer 44 protrudes outwards from the tank wall or top 7, which retains an inwardly projecting tab or flange 45 for receiving the base flange 43, whereby the member 3 ) Can be fixed securely to the wall or top 7. Retainer 44 may include, for example, a single piece peripheral member 3 to prevent its movement relative to the wall or top 7 in any direction. Peripheral member 3 is a U-shaped channel for receiving rigid or semi-rigid insulating panel 46. In this embodiment, the U-shaped channel comprises a channel collar and flanges (or flanges) 3, which are flanged collars 47 fixed to the member 3 in cooperation with the member 3. By this arrangement, the panel 46 is held outside the tank wall or top, parallel to its plane. Other variations for fixing the thermal insulation panel using the member 3 are within the state of the art.

Referring to FIG. 5, a cold semi-membrane tank 51 is shown having a bottom portion 52, forward and backward protruding sides 53, and an upper end 54. Also for purposes of illustration, when they are present at room temperature, the top 55 and side edges are shown. As shown in FIG. 5, the wall 53 is joined to the bottom portion 52, the top portion 54, and to each other by a radial edge 56 whose intersection is a radial corner. . Curve 60 shows the curvature of the radial edge 56 in the cold state at the middle length of the rearward protruding wall. The tank bottom portion 52 is placed on the load bearing insulation 57. The peripheral support structure includes a vertical member 58 spaced outwardly from the wall 53 and a horizontal member 59 spaced outwardly from the upper end 54. The peripheral support structure also includes a horizontal member that is not shown for clarity of illustration. A horizontal row extending around the side 53 of the tank 51 is shown a support assembly connecting the side 53 to the vertical support member 58. In this embodiment, one row, ie the bottom row, is a two-dimensional support assembly 1 arranged horizontally inclined in a direction away from the vertical center line of the wall extending downward from the center point of the expansion dome 61 (FIG. 1). It consists of). In the assembly 1, the crosshatching of the orthogonal parallel lines represents the extent to which the member 2 is offset from the member 3 due to the cooling of the tank. The assembly closest to the centerline of the wall has the smallest offset and the assembly farthest from the centerline has the most offset. A row of assemblies 1 extending around the tank circumference provide vertical support for each tank wall. The thermal fixation point 62 of the turning wall 53 is indicated by "X". Additional rows of the support assembly are shown on the wall 53. These are also three-dimensional assemblies 21 (FIG. 2) which are arranged to be inclined in a direction away from the center line in a horizontal direction, ie the vertical line extends through the fixing point. In addition to offsetting the members 2, 3 along the slope as shown by the orthogonal shading, the assembly 31 is allowed for thermal movement in a direction (not shown) across the slope. A support assembly 21 which connects the vertically arranged upper end 54 to the horizontal support member 59, which is inclined in a direction away from the centerline of the upper end 54 through the center of the expansion dome 61. The line of is shown. Here again, there are more offsets between the members 2, 3 at the outer periphery of the tank than in the fixing point of the upper end, in this case in the vicinity of the line through the center of the expansion dome 61. The support assembly for the tank top 54 may be arranged in a grid pattern similar to the pattern shown for the forward wall 53. In this case, the support assembly along the vertical line passing through the fixing point is the assembly 1 inclined in a direction away from this point. An additional support assembly is an assembly 21 similar to the arrangement shown for the front-facing wall 53.

6 shows an alternative embodiment of an array of support assemblies for the wall 53 of the tank 51 in the cold state. This embodiment comprises a row of support assemblies 1 which are inclined in a direction away from the fixing point 62 and arranged horizontally, similar to the embodiment shown in FIG. 5. This embodiment includes an additional support assembly 1 which is radially oriented so as to be inclined in a direction away from the anchor point 62. Although the support assembly 1 prevents movement across the slope, the radial orientation shown in FIG. 6 results in movement along the slope with both a vertical component and a horizontal component parallel to the plane of the wall. Thus, it causes the wall 53 to contract both in the vertical and horizontal directions towards the anchor point 62. In this embodiment, the radial edge 56 of the upper end of the tank 51 is basically uniform and there is a unique curvature 60 at the central length of the wall, as is present in the embodiment shown in FIG. Be careful not to. Instead, in this embodiment, the profile of the rearward projecting wall 53 at its central length is shown by line 63.

6 also shows a preferred way to construct an array of support assemblies for a cylindrical tank. 6 shows a vertical column of support assemblies arranged vertically extending upward from point 62. For cylindrical tanks, the thermally invariant circle is a circle extending horizontally around the tank wall through point 62. The vertical column of the support assembly 1 is augmented by an additional vertically disposed assembly at, or slightly above, the point 62. All other support assemblies of FIG. 6 have been replaced with additional vertical columns of the support assembly 1 spaced around the tank wall.

FIG. 7 shows an array of support assemblies 1 on the tank top 54 in the cold state. The array shown in FIG. 7 has an assembly 1 inclined in a direction radially away from the fixation point 62 which is the center of the expansion dome 61. Also shown in FIG. 7 is the top row of the support assembly 21 (FIG. 5) in cross section. In this figure, one can see the increasing offset of the member 23 at the end of the tank wall 53, compared to the centerline of the wall. The array shown in FIG. 7 is likewise suitable for the circular top of a cylindrical tank.

It should be noted that the number of support assemblies shown in FIGS. 5-7 need not necessarily be the ones used for the actual semi-membrane tanks. The number and layout can vary depending on the design requirements.

8 shows one sidewall 53 having an interconnect support assembly 21 (or 1) and a peripheral support structure 58 suitable for construction outside the outer containment structure 80. The preassembly of the semi-membrane tank, peripheral support structure and interconnect support assembly is hoisted by a crane and lowered into an outer containment structure, such as the inner hull compartment of an LNG tanker. 8 shows an outer containment structure 80 installed with a plurality of vertical keyways 82. Although the structure 80 in FIG. 8 is schematically shown as a wall with a keyway, the vertical support member with the keyway 82 as a beam or hull protrudes therefrom inwards towards the peripheral support structure 58. It will be appreciated that the structure 80 can likewise be multiparted. 8 also shows a series of vertically extending keys 81 rigidly attached to peripheral support structure 58. 8 shows one key-keyway pair aligned with the thermal fixation center, but this is not required. Our preferred configuration is that the key 81 itself is a vertical member of the support structure 58. For ease of illustration, the keyway 82 and the complementary key 81 are formed to be tapered, ie larger at the top of the tank. Keys and keyways can be reversed. That is, the key may be on the outer containment structure and the keyway may be on the peripheral support structure. Keys and keyways can be interlocked in various ways within the current level of the art. The system of key and keyway is provided for at least two opposing planar sidewalls. This may be provided for some or all additional walls. For cylindrical walls, the key and the system of keyways are provided for at least two opposing arcuate sections of the wall, which can be provided for the entire outer circumference of the wall.

9 is a cross section through support assembly 92, 93, 94, which is an alternative configuration to that shown in FIG. 4. This may be either a two dimensional support assembly as shown in FIG. 1 or a three dimensional support assembly as shown in FIG. Similarly, a three member, three dimensional support assembly (FIG. 3) may be utilized. A two dimensional support assembly is shown. Similar to the member 2 of FIG. 4, the support assembly is firmly attached to the structure 105, which may be a peripheral support structure, in this case a support structure member such as the member 58 (FIG. 5) or an inner hull of a double hull tanker. Similar to the fixed first member 92 and the member 3 of FIG. 4, the outer side of the semi-membrane tank shown in FIG. 9 as the plate tank side 97 bent through the load bearing insulating block 94. And a second member 93 which is firmly fixed thereto. The interface between the members 92 and 93 is an inclined surface similar to the inclined configuration shown in the side view of FIG. The support assembly member 93 is firmly secured to the insulating block 94 by one or more bolts 95. The insulating block 94 is attached with a pair of angled retainers 96 for receiving rigid or semi-rigid insulating panels 102.

The support assembly arrangement shown in FIG. 9 is particularly suitable for use with the curved plate-structured semi-membrane tank described in US Pat. No. 5,727,492. 9 shows a portion of a vertically curved plate tank wall or side 97 that includes a tip forming a joint between two of a series of horizontally arranged curved plate sections. Extending outwardly from the tip 98 and being integrally formed or secured to it are the T-bars in this embodiment for attaching the second member 93 to the wall 97 at the tip 98. It is a molded fixed structure that firmly couples to the insulating block 94 that is 99. The thermal insulation block 94 includes a notch 100 shaped to conform to the T-bar 99, thereby firmly securing the support assembly to the tip 98 of the side wall 97. Optionally, block 94 may be two parts that can be secured to each other by a series of bolts, such as bolts 95, and dividing line 106 is shown in FIG.

In the curved plate embodiment shown in FIG. 9, because the curved section of the tank wall 97 can be curved to relieve stress in the vertical direction (cord of the bending section), the support assembly is a two-dimensional support. Assembly. Each horizontally extending tip connected to the outer support structure 105 by a two-dimensional support assembly moving in and out and laterally thus resembles the bottom row of the assembly 10 of FIG. Like), they provide vertical support for the tank wall 97. Thus, each wall 97 of the four-sided curved plate tank is generally a thermal fixation point at a position along each tip 98 at the horizontal center of the wall, in other words a series of vertical points 62. Has a point 62 (FIG. 5) in the row of each of the support assemblies forming a. In each row, the support assembly is arranged to have an inclined direction as shown for the bottom row of FIG. 5.

Inclined sidewalls to regulate the force vertical contraction and expansion to be accommodated by the change in radius of the curved plate and the vertical movement of the tip 98 (sidewall of the two-dimensional assembly is shown as element 12 in FIG. Instead of using the one shown and detailed in the description of this figure, an alternative is to maintain vertical separation between successive rows of the support assembly by other means. Shown in FIG. 9 is, for example, a beam 103 such as an I-beam or an H-beam, which is through the hole 104 of the member 93 and the tip of the top and bottom of the tip 98 (not shown). In the vertical direction through the aperture of the member 93 in the column of the assembly. Beam 103 is firmly attached to member 93 in the column of the assembly. Additional beams 103 are similarly arranged and attached to other columns of the assembly such that there is a series of beams 103 extending along each tank wall (see FIG. 5).

The beam 103 prevents the tip 98 from moving vertically relative to each other, thereby forcing the curved plate into the wall 97 to accommodate vertical thermal expansion. It will be appreciated that this allows for the simplification of the inclination enclosure structure shown in FIGS. 1 and 9 since movement across the inclination does not need to be prevented.

A series of beams 103 extending along each tank wall also provide a means for raising the tank wall using a lifting jig. An example of a lifting system is to provide a hole 107 in each beam 103 at the top thereof so that the pipe can slide through the hole 107 on each tank side. The pipe (not shown) preferably comprises a removable member of the lifting jig, but can be slidably attached to the beam 103. Using the preferred embodiment, the tank, support assembly and beam 103 can be constructed and fully assembled outside of the support assembly. The assembly member 92 may be inclined inwardly toward the tank wall 97 to provide an installation clearance. The entire assembly can be lowered into the support assembly, after which the member 92 is inclined to engage the outer support member 105 and secured thereto by welding or the like.

A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, loose fit between interlocking support assemblies, thermal gradients between different locations in a tank, or adjustable slopes of sliding surfaces or other means to accommodate manufacturing tolerances, metal attached to load bearing insulating blocks Features such as the construction of the mating surface of the inclined portion are all potential variations within possible alternatives that may immediately be apparent to those skilled in the art. Accordingly, other embodiments exist within the scope of the following claims.

Claims (20)

A support assembly for attaching a wall or top of a semi-membrane tank to a peripheral support structure, A first member fixedly attachable to the peripheral support structure, and A second member fixedly attachable to the tank wall or to the upper end, The first and second members allow movement of the second member relative to the first member in a direction parallel to the livestock of the inclined surface and prevent movement of the second member relative to the first member in a direction perpendicular to the inclined surface. And reciprocally complementary angularly inclined surfaces slidably coupled in a manner. The support assembly of claim 1, wherein the mutually complementary angularly inclined surfaces are slidably coupled in a manner that prevents movement of the second member relative to the first member in a direction transverse to the inclination. The support assembly of claim 1, wherein the mutually complementary angularly inclined surfaces are slidably coupled in a manner that allows movement of the second member relative to the first member in a direction transverse to the inclination. 4. The support assembly of claim 1, wherein the second member is rigidly attachable to the wall or top through a load bearing insulation. 5. The support assembly of claim 4, wherein the load bearing insulation is a block comprising two pieces that can be secured to each other. 6. A support assembly as claimed in claim 4 or 5, wherein the load bearing insulation comprises a notch that conforms to the shape of the fixed structure projecting outwardly from the tank wall or top. The support assembly according to claim 1, wherein the second member is configured to secure the thermal insulation panel to the tank. In a support system for the flat wall of a semi-membrane tank, The support system provides at least one thermal fixation point for each wall, A vertically extending support structure surrounding the tank and an array of support assemblies spaced apart over an outer surface of each wall connecting the walls to the peripheral support structure, The array comprises a plurality of support assemblies according to claim 2 oriented horizontally with a second member inclined in a direction away from the at least one point while being horizontally spaced from at least one thermal fixation point. Thereby providing a vertical support for each wall and allowing the second member to move in a horizontal direction in an oblique direction parallel to the plane of the wall and in a direction perpendicular to the plane of the wall. The support system of claim 8, wherein the array comprises a plurality of support assemblies according to claim 3. 10. The support system of claim 9, wherein each of the walls has one thermal fixation point that does not have a rigid attachment connecting the tank wall to the peripheral support structure. 11. The method of claim 10 wherein the thermal fixation point of each wall is adjacent to a vertically low point of the wall at approximately the horizontal center point of the wall, An array of supports spaced apart over the outer surface of each wall comprises a plurality of support assemblies according to claim 2 arranged radially spaced from the thermal fixation point, arranged to be inclined away from the thermal fixation point. The support system according to claim 8, wherein the support assembly according to claim 1 is arranged such that the second member is inclined away from the line extending vertically through the at least one thermal fixation point. The support system of claim 8, wherein the support assembly is rigidly attachable to the wall via a load bearing insulation. 10. The system of claim 8, wherein the walls have a curved plate structure with horizontally extending tips between the curved plates, A support system comprising an array of support assemblies according to claim 2 arranged along the tip. The support system of claim 14, wherein the support assembly is arranged to form a vertical column of the support assembly. The method of claim 15, further comprising a vertically oriented structural beam, Each beam is fixedly attached to a second member of at least two support assemblies of the vertical column of the support assembly. The tank of claim 8, wherein the tank comprises a top end, and the peripheral support structure comprises a horizontally extending top end support structure above the top end of the tank, Providing an thermal fixation point, the array further comprising an array of support assemblies according to claim 1 disposed radially spaced apart over the surface of the upper end, The support assembly includes a first member rigidly attached to the peripheral support structure and a second member attached to an upper end having an inclined surface oriented in a direction radially away from the rigid attachment point. 18. The support system of claim 17, wherein the second member is rigidly attached to the top end via a load bearing insulation. The tank of claim 8, wherein the tank comprises a top end, and the peripheral support structure comprises a horizontally extending top end support structure above the top end of the tank, And a support assembly according to claim 1 arranged in a grid pattern across the top, the rigid attachment portion rigidly securing a point of the top end to the top support structure. 18. The support system of any one of claims 8 to 17, further comprising a vertical key engageable with a keyway attached to two or more parallel sidewalls and their respective peripheral support structures.

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