GB2260359A

GB2260359A - Covers for liquid containers

Info

Publication number: GB2260359A
Application number: GB9121706A
Authority: GB
Inventors: Robert Paterson Mcgregor; Rosemary Mcgregor
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-10-12
Filing date: 1991-10-12
Publication date: 1993-04-14
Anticipated expiration: 2011-10-12
Also published as: GB9121706D0; WO1994018411A1; GB2260359B

Abstract

The invention relates to covers for tanks, large storage vessels and the like. The cover may be circular, oval or rectangular in plan and comprises a plurality of panel members (4) each member, which may be of glass-reinforced plastics and made in several sections if necessary, forming, in plan view, at least part of a sector of a circle. Each panel member (4) is provided with a depending flange (6) on each edge, the flanges being used to join the panel members together along their radially extending sides. In order to provide boundary layer air control in the case of large area covers, the panel members (4) are stepped longitudinally, as at (20). The cover may have a central aperture (24) closable by a lid. <IMAGE>

Description

COVERS FOR LIOUID CONTAINERS The invention is concerned with improvements in or relating to covers for liquid containers, particularly but not exclusively tanks and other large-size containers for liquids for example in the context of purification, storage or other treatment of industrially contaminated water or other effluents.

It will be understood that large size tanks which may be circular or rectangular in plan may require to be closed by a relatively close-fitting cover of a large size which may be difficult to manufacture and handle in the normal way. A circular cover may be required for a tank which is 30 metres or more in diameter. A cover of sufficient size for such a tank also presents problems in use, since the cover which may be close-fitting will not be effectively airtight and will therefore be liable to the adverse effects of high winds, which may lift the cover or may greatly damage it.

The invention therefore provides a cover for a container, comprising a plurality of elongate panels members, each panel member having at least three edge portions comprising first and second opposed edge portions which converge towards a first end portion of the panel member and a third edge portion which connects said first and second edge portions at a second end portion of the panel, said panel being provided with an upper surface having a serrated lengthwise extending profile, each of said panel members being secured to an adjacent panel member by abutment of its first edge portion to the second edge portion of an adjacent panel member, wherein all said first end portions of the panel members occupy an at least substantially central zone of the cover and said serrated profile is formed by a plurality of component steps.

Conveniently, said third edge portions of the panel members of the cover may describe the perimeter of a circular layout. Advantageously, each panel comprises a fourth edge portion situated at its first end portion, said fourth edge portions describing a circular aperture, there being provided a circular closure member adapted to close said aperture.

Conveniently, each said first and second edge portion of each panel member comprises an inwardly turned flange adapted to be secured to a flange of edge portions of adjacent panel members. Advantageously the panel member is arched between said first and second edge portions.

There will now be described an example of a cover according to the invention. It will be understood that the description which is to be read with reference to the drawings, is given by way of example only and not by way of limitation.

In the drawings: Figure 1 is a diagrammatic perspective view of a cover; Figure 2 is a side of one panel member of the cover of Figure 1; Figure 3 is a view in vertical section through the cover including a closure portion; Figure 4 is a fragmentary sectional view of a join area of a panel member; Figure 5 is a side view of the closure portion to an enlarged scale; Figure 6 is a fragmentary view of the securing means between the cover and the closure means; Figure 7 is a plan view of panel members of the cover; Figure 8 is a detailed view of a panel member securing means; Figure 9 is an end view of an outer end portion of a panel member; Figure 10 is a side view of a panel member including an inspection hatch; Figure 11 is a similar side view showing a vent device; Figure 12 shows a closure device for the vent of Figure 10; and Figure 13 shows the fixing of the cover to a tank.

The cover 2 shown in Figure 1 is suitable for a circular tank T and is formed from a plurality of panel members 4 which form at least a part of a sector of a circle describing the perimeter of the cover. Each panel member is provided with a flange 6 on first and second opposed edge portions 8,10 which are formed on radii of the cover circle and therefore are convergent. Third edge portions 12 of each panel member 4 which in the presently described circular layout are formed on an arc of the perimeter, are also provided with flange portions 16 adapted to permit attachment to the tank.

It will be understood that a tank which is non-circular will require a rectangular or oval cover in which the third edge portions together define the perimeter shape and may therefore be linear, curved and oblique as required.

In the example shown in the Figures, each panel member 4 is arched between the edge portion 8 and 10 and therefore end wall portions 18 are provided to close the outer end portions of the panel members.

As shown in Figures 2 and 3, each panel member has a longitudinal profile which is stepped at 20. It is envisaged that this configuration will be found to provide boundary layer air control even under conditions of severe gales, in which a non-stepped contour would tend to be lifted by the force of the wind.

Each panel member 4 may be constructed in a single unit by a moulding technique using glass-reinforced plastics material or in situations where the diameter of the tank to be covered is large, each panel member may be constructed in two or more portions and joined together, at an intermediate area, conveniently at a step 20 as shown in Figure 4.

Each panel member 4 also comprises a fourth edge portion, 22, at an inner end portion thereof with respect to the cover, so as to form a central aperture 24. An annular retaining member 26 received flange portions 6 of all the edge portions 22 in an outwardly facing recess 28, see Figures 5 and 6. A closure member 30 is then fitted over the retaining member 26.

Figure 8 shows a portion of one panel member 4 adapted to be joined by bolts to adjacent portions to form the complete panel member. Figure 9 shows the curvature of the arched construction of the panel member, the differing degrees of curvature of an outer end of a panel member portion 4a and the inner end of an adjacent panel member portion 4b producing the step 20.

Figure 10 illustrates the provision of an inspection opening having a hatch 32 formed adjacent the end wall 18 of one of the panel members 4 and Figure 11 is a sectional view through a vent device 34 provided in the end wall of another panel member 4, having a hinged shut-off plate 36, as shown in Figure 12.

Figure 13 shows the attachment of the complete cover to tank T by means of bolts passing through the flanges 16 into brackets 38 of the tank.

Various modifications may be made within the scope of the invention.

Claims

CLAIMS:

1. A cover for a container, comprising a plurality of elongate panel members, each panel member having at least three edge portions comprising first and second opposed edge portions which converge towards a first end portion of the panel member and a third edge portion which connects said first and second edge portions at a second end portion of the panel, said panel being provided with an upper surface having a serrated lengthwise extending profile, each of said panel members being secured to an adjacent panel member by abutment of its first edge portion to the second edge portion of an adjacent panel member, wherein all said first end portions of the panel members occupy an at least substantially central zone of the cover and said serrated profile is formed by a plurality of component steps.

2. A cover as claimed in claim 1, wherein said third edge portions of the panel members describe the perimeter of a circular layout of panel members.

3. A cover as claimed in claim 2, wherein each panel comprises a fourth edge portion situated at its first end portion, said fourth edge portions describing a circular aperture, there being provided a circular closure member adapted to close said aperture.

4. A cover as claimed in any one of the preceding claims, wherein each said first and second edge portion of each panel member comprises an inwardly turned flange adapted to be secured to a flange of edge portions of adjacent panel members.

5. A cover as claimed in any one of the preceding claims, wherein each panel member is arched between said first and second edge portions.

6. A cover as claimed in claim 5, wherein end wall portions are provided to close outer end portions of the panel members.

7. A cover as claimed in any of the preceding claims, wherein each panel member is constructed by using a mouldable material.

8. A cover as claimed in claim 7, wherein the material is glass reinforced plastics material.

9. A cover as claimed in any of the preceding claims, wherein the panel member is formed from a plurality of portions combined together at an intermediate region thereof.

10. A cover as claimed in any one of the preceding claims wherein there is provided an opening suitable to act as a inspection port for viewing the contents of a container under the cover.

11. A cover as claimed in any one of the preceding claims, wherein there is provided a vent device said vent device comprising a shut-off means for preventing the egress of gasses and vapours.

12. A cover for a container, constructed and arranged substantially as hereinbefore described with reference to and as shown in the drawings.