AU687987B2 - Storage tanks - Google Patents

Description

AUSTRALIA

Patents Act 1990 Name of Applicant ENCON HOLDINGS PTY LTD (ACN 053 011 993) Actual Inventor(s) GEOFFREY RONALD OXENFORD Address for Service GRANT ADAMS COMPANY Patent Trade Mark Attorneys Level Santos House 215 Adelaide Street BRISBANE QLD 4000

AUSTRALIA

Invention Title STORAGE TANKS Details of Associated Provisional Applications Numbers PM4996 The following statement is a full description of the invention including the best method of performing it known to me.

THIS INVENTION relates to storage means including tanks, silos, containment means and the like.

For the sake of convenience the invention will hereinafter be referred to as simply a storage means.

Storage means are provided to a range of industries and to meet a variety of needs. Many different techniques have been used to enable production of individual and particular storage means. One form of storage means is established by joining a plurality of vertically extended, arcuate segments, the segments being joined together and braced along their vertical edges along a line along which a substantial vertically oriented beam is placed. This beam interacts with substantial perimeter beams or other structures at top S 15 and bottom. The vertical beam provides a means by which to hold the segments and stabilise the storage means' vertical wall. Whilst storage means of this kind have met with some success there is a continuing need to refine the character of such means with improvement particularly in parameters such as with those costs which are determined by material requirements and the like.

It is an object of the present invention to provide a storage means with reduced material outlays.

Reduced material outlays can realise cost savings. Other objects, and various additional advantageous characteristics will hereinafter become apparent.

The invention achieves its objects in the provision of a storage means for the containment of fluids and the like, said storage means being enclosed by a generally cylindrical, vertical, peripheral wall, said storage means comprising: a plurality of vertically extended, modular, wall elements which are arcuate between vertical edges, said wall elements being joined edge to edge along their respective vertical edges, the panels being disposed convex surface outwardly the radius of curvature of each wall element being less than that of the storage means; vertical framing members at the vertical edges between adjoining wall elements; and bracing means extended horizontally across the wall elements between vertical framing members.

The storage means of the above type is particularly suited to use with liquids. Ideally they are assembled by a modular approach utilising prefabricated elements.

The construction realised by the present invention enables walls with thinner sheets of material and less substantial bracing elements. It is by these means that costs are diminished.

The following abbreviations are used herein with their common meanings applying as follows: FMS denotes flat mild steel; *I CHS denotes circular hollow steel; and S 20 RHS stands for rectangular hollow steel.

The invention will now be described with reference to preferred embodiments as are shown in the accompanying drawings wherein: FIG. 1 shows a general view of a storage tank in accordance with the present invention.

FIGS. 2 and 3 show alternate means by which a storage tank of the type in FIG. 1 may be braced.

FIG. 4 shows a roof structure which might be applied to a storage tank of the type shown in FIG. 1.

FIGS. 5 to 7 show details of the roof structure of FIG. 4.

FIGS. 8 to 15 show details of various points in the structure where connections are effected.

A tank in accordance with the invention might be constructed from sheet material which is configured in short arcs (short in the sense that they are short relative to the circumference of the tank itself), each *vT having a radius smaller than that of the tank, made up into a plurality of modular sheet material wall elements to be used in series about the perimeter of the storage tank. The plurality of modular wall elements are joined in the series along their vertical edges along vertical lines extending the height of the tank. The vertical modular wall elements extend about the periphery of the storage tank to constitute the vertical containment surface of the storage tank. In practice short arcuate elements or segments, with a one to two metre radius, can be used. As the stresses induced in a curved sheet wall are proportional to the radius of the arc, relatively thin thicknesses of sheets can be used in each of the arcs irrespective of the overall tank 15 size. Larger diameter tanks are realised simply by adding to the number of arcuate or segmental elements or members used.

In the storage tank of the present invention, the individual arcuate segments are tied together by either of internal or external bracing (as will be .described below) using, possibly, standard FMS or galvanised angles. The bracing provides for structural integrity in the tank. Because the storage tank will tend towards being a circular shape under internal pressures, it is held in or forced to maintain its 'clovered' shape by such bracing, suitably sized and extended either internally or externally across each wall segment or arcuate sheet member.

In FIG. 1 the tank 10 comprises a series of arcuate wall elements or segments such as 11 and 12, joined to each other along their respective edge along a vertical line 13 therebetween. The curvature of each arcuate segment is maintained by a series of braces or tension members (described in greater detail below) such as 14, extended across the segments and thereby extended between the joins such as, for example, between panels 11 and 12, and 12 and 15 respecti-rely, so as to span arcuate element 12 and resist internal pressures which would otherwise stretch the wall segment 12 and extend it to a radius equal to that which is defined by the total perimeter of the tank which is determined by the total length of the series of arcuate segments or elements. Each arcuate segment can be built from a vertical series of bolted sheets with sheets bolted along lines such as 16. Each segment might be a single sheet in small tanks, but on larger tanks employing S.larger arcs and greater heights, stock sheet material .:eo suited to a unitary construction may not be either available or even desirable, given other factors such as 15 transportation, assembly needs, etc. Each arcuate segment can be braced by a plurality of bracing elements such as 14 in FIG. 1.

The top edge of each arcuate segment can be fitted with a complementary arcuate brace as also can be the bottom, and equivalents of the arcuate brace might be applied to the storage tank at points along its vertical height to add to stability. Arcuate braces might be applied more frequently at lower levels where stresses resulting from internal pressure are greatest.

In FIG. 2 is seen in detail how the bracing across arcuate segments or elements can be established internally of the storage tank. Arcuate wall segment 17 is spanned by a tension member 18 which, in this embodiment, is bolted at 19 and 20 to the wall sheets and an external brace such as 21 at point 19. A bolt 22 passes through the edge flanges of adjoining arcuate wall sheets and through the tension member 18. The vertical brace 21 extends the height of the wall and bolts are provided at repeated centres to fix adjoining wall panels and additional internal bracing elements, spanned across the arcuate members, as desired. The vertical brace 21 might be a length of angle iron as shown. The brace 18 might be an FMS or angle. The sheets and the bracing can be kinked or flattened at an appropriate angle to permit the join as shown at the joins in the figures.

An alternate means for bracing a storage tank is shown in FIG. 3. Here the tension or bracing members 23 span across compression members such as 24 and which act on vertical braces 26 and 27 respectively to resist spread across the points 29 and 30 under internal pressures. Thus the shape of sheet 28 is retained and internal pressures are resisted. It is bolted as before to vertical members such as 26 at centres therealong o" 15 from top to bottom of the tank. The compression members may be CHS, RHS or angle with end brackets at which bolts may be applied to engage with the other elements of the system.

The bracing members are illustrated as being separate lengths between vertical joins of the arcuatr segments. Other arrangements are possible. The bracing members might extend i1 and more segments and their ends can be joined one to the other at points between the vertical joins of the arcuate members.

FIG. 4 shows a self supporting roof which can be applied to the tank of FIG. 1 in accordance with the invention. This has a centre bracket which ties inclined purlins to a horizontal strut to form a strong triangular shape.

In FIG. 4, roof 31 is formed with a diagonal strut 32 with a tension element tied between the outer end of beam 34 and a centre bracket 35 with a mirror imame arrangement at the opposite side of the centre bracket 35 which lies in use along the axis of the tank.

Purlins such as 36 are stood off the periphery of the storage tank vertical wall at an inclined angle and extended to beam 34 or bracketed thereto.

In FIG. 5 is seen a detailed view in which tension member 37 is bolted to beam 38 at point 39. At the end of beam 38 there is bolted a bracket 40 with a support plate 41 which supports the roof by overlying the top of the tank.

In FIG. 6 is seen how purlin 42 is fixed to beam 38 by back to back L-shaped brackets 43 fixed to beam 38 which brackets establish a lug by which purlin 42 is fixed. In FIG. 7 is seen a detail of the centre :..bracket 35 which is formed with wings at which each of the roof members are bolted. Each purlin can be fitted with an end bracket with a support flange such as 46 in 15 FIG. 5 orieated at an appropriate angle to drop into the upper edge of the tank wall.

FIG. 8 shows a detailed view of the means by which the parts are assembled. The sheet material 43 providing the containment wall of the storage means is clamped between a typically steel flat 44 and an angle 45 by a bolt 46 and nut 47 acting against washers 53 and .see° 54 respectively. The internal braces 48 and 49 are caught on bolt 46 with their respective end portions and 51 having a hole therein to be threaded onto the bolt for capture by nut 52.

FIG. 9 shows a detailed view of the means by which an external brace can be fitted. As seen in FIG.

8 the sheet material which forms the containment wall of the storage means is clamped between a flat 57 and an angle 58 by a bolt 64. A radial compression member 59 is fitted to bolt 64 and held thereto by a nut 65. The compression member 59 is formed by a length of angle with an end piece of angle 66 welded thereto to provide an end flange 60 to receive bolt 64. The compression member 59 has its other end cut to form a flat 60 which can be holed at 63 to take a bolt which attaches two tension members or braces 61 and 62. The braces are angles which are oriented oppositely so that they stand off opposite surfaces of the flat FIG. 10 is a detail which shows the use of a compression member with an internal brace. The sheet material of the wall 67 is clamped between a flat 68 and an angle 69 by a bolt 70 to which a compression member 71 (formed in similar manner to that of FIG. 9) is bolted, projected radially towards the centre. Angle iron type braces 72 and 73 are attached to the compression member 71 by a bolt through hole 74 in a similar manner to that which is described with reference o.a.

to FIG. 9.

15 FIG. 11 shows a variation with an internal brace. Sheet 75 is fitted with vertical elements at 76 of the above type to which a compression member 77 is fitted. The internal brace in this case is formed with angles 79 and 80 attached to a bracket 78 on member 77, which bracket can be an angle, oppositely oriented and welded thereto. The angles 79 and 80 are attached at there other ends to angle 81 which can be bolted to member 77 at 82. FIG. 12 shows the layout at larger scale. This form of construction results in extra rigidity during construction.

FIG. 13 shows a detail at the inner wall of a storage tank braced internally by flat material.

Vertical flat 83 is the above described means by which the wall sheets are attached to an external vertical beam. Flat strip material braces 84 and 85 are attached at 86 by a bolt (not shown).

FIG. 14 shows a detail at the top of the storage means. Vertical angle 88 is attached to top angles 89 and 90 by means of flat 91.

FIG. 15 shows how the vertical member can be constructed out of modular lengths of angle. A short angle 93 bridges longer angles 92 and 94 to form a joint therebetween. This pattern can be repeated p the height of the wall.

Whilst the drawings illustrate a series of identical arcuate segments, the advantage of the invention might still be realised with two or more different radius arcuate segments randomly added into the series about the tank, or incorporated therein in some regular pattern. The materials will typically be metals such as stainless and/or mild steels but other omaterials might be applied as wall panels, bracing .eee elements, etc, dependent on the properties of materials to be contained, size of tank and cost of materials.

15 The tank might be provided with a liner to contain fluids, or joints between components may be sealed after construction, or with a sealant applied prior to establishing the joints between respective components.

A sealing strip or sealing means might be applied to the joint between the wall and the roof to exclude vermin, establish a weather seal, or otherwise protect the integrity of the joint therebetween as is dictated by E. those needs which give rise to the existence of the storage tank.

Claims (9)

1. 2. A storage means as claimed in Claim 1, wherein the bracing means extends internally across the width of a single wall element, spanned between its vertical edges, the bracing means being connected thereto to serve as a tension member thereacross.
2. 3. A storage means as claimed in Claim i, wherein the bracing means extends externally across the width of a single wall element, the bracing means being stood off the vertical framing members on compression members extended radially outwardly therefrom.
3. 4. A storage means as claimed in any one or more of Claims 1 to 3 wherein the bracing means comprises flat metal ribbon attached by bolts passed therethrough. A storage means as claimed in any one of claims 1 to 3 wherein the bracing means is formed from angle iron.
4. 6. A storage means as claimed in claim 5 wherein the braces are stood off the wall on radial elements and a strut bridges adjoining braces and the radial element.
5. 7. A storage means as claimed in any one or more of Claims 1 to 6 wherein, the wall elements are arcuate panels which aie formed from sheet material formed in an arc between flat edge flanges which flanges, at respective adjoined edges, overlap and said edge flanges are connected by suitable connection means to the vertical members.
6. 8. A storage means as claimed in any one or more of Claims 1 to 7 wherein each wall element is constructed by joining a plurality of curved sheets edge to edge to establish the requisite height therein.
7. 9. A storage means as claimed in claim 8 wherein S. 15 a wall element is provided with an arcuate brace at the horizontal join between sheets. A storage means as claimed in claim 9 wherein a plurality of said arcuate braces are applied to a wall element, increasing in number towards the base of the wall.
8. 11. A storage means as claimed in any one of claims 1 to 10 wherein the storage container is fitted with a generally conical shaped lid formed with purlins sloped from a centre bracket to an end bracket rested on said wall elements, the centre bracket being stood off a horizontal strut extended between said end brackets.
9. 12. A storage means for the containment of liquids and the like substantially as hereinbefore described with reference to the accompanying drawings. DATED this Twelfth day of April 1995. ENCON HOLDINGS PTY LTD By their Patent Attorneys GRANT ADAMS COMPANY 12 ABSTRACT TITLE: STORAGE TANKS A storage means. (10) is 4formed with vertical wall elements (11, 12) joined on a vertical line (13) with braces (14) internally or externally (23) stood off radial posts (24) with a lid (31) applied thereto. 0* *so*: