GB2171635A

GB2171635A - A method and mould for casting bitumen or the like

Info

Publication number: GB2171635A
Application number: GB08505203A
Authority: GB
Inventors: Norman Seddon
Original assignee: F D L PACKAGING Ltd
Current assignee: F D L PACKAGING Ltd
Priority date: 1985-02-28
Filing date: 1985-02-28
Publication date: 1986-09-03
Also published as: GB8505203D0

Abstract

The invention relates to casting and moulds for bitumen or the like. The mould (10) comprises a length of foldable material folded into a three or more sided pipe having a portion (L in Fig 3) at an end of each side folded over to provide a substantially flat and substantially complete base (Fig 2), whereby the pipe can stand substantially vertically when placed on the base. Thus a free-standing mould can be provided from a single piece of foldable material. The mould receives and holds liquid bitumen which subsequently soldifies so that the mould is thereafter effectively packaging. <IMAGE>

Description

SPECIFICATION A method and mould for casting bitumen or the like This invention relates to casting and moulds therefor, and more particularly to casting and moulds for bitumen or the like.

Bitumen is employed in the road making and roof sealing industries in addition to other uses. In these industries, solid bitumen is transported to a site for use, whereupon the bitumen is heated into a liquid form suitable for the appropriate application. It is clearly inappropriate in the majority of cases to transport liquid bitumen since this requires the continual application of heat. Consequently, manufacturers of the bitumen product from raw materials have wought appropriate means of solidifying the bitumen into a form suitable for transportation. It has been known to pour basic liquid bitumen (that is to say bitumen just produced from raw materials) into a tray, allow solidifcation and subsequently break-up the solid bitumen into small pieces for transport.The disadvantage of this method is the requirement to have a large number of trays and in addition it is necessary to have a step of breaking up the bitumen into pieces. Furthermore, in some applications it is important that the bitumen is not contaminated. Accordingly, where bitumen is broken up and transported some contamination can occur.

A known alternative method has been to take a rectangular length of siliconised heavy duty paper and form it into a cylinder by typically gluing the opposite edges together. The cylinder so formed, with the silicon surface internal, is placed in a circular metal base and the circumference of the base is crimped so as to attach to the lower end of the cylinder. In this way a self-standing mould is produced. The mould is then filled with liquid bitumen and then left to cool. When the solid bitumen packaged in the paper is used, the brown paper is simply stripped off the cylinder of bitumen.

The problem with the last mentioned method of packaging liquid bitumen is that the production process requires the formation of the paper cylinders and their subsequent attachment to the metal bases. This is a time consuming step, and in addition apparatus for the attachment step can be expensive.

Although pre-formed moulds could be formed, transportion of the pre-formed moulds to a bitumen filling plant would be space-consuming.

Finally, the use of metal and paper in the mould increases raw material costs of each mould.

It is therefore an object of the invention to obviate the above mentioned problems and to provide an improved and more cost effective mould and method of packaging bitumen or the like.

According to one aspect of the invention, there is provided a mould for bitumen or the like comprising a length of foldable material folded into a three or more sided pipe with a portion at an end of each side folded over to provide a substantially flat and substantially complete base, whereby the pipe can stand substantially vertically when placed on the base. In this way a mould for bitumen or the like is provided from a single sheet of material, thus reducing production costs. In addition, having the base formed by folding of the portions at the end of each side avoids the necessity of having a step of attaching the sides to the base. Thus, a free-standing mould can be provided from a single piece of foldable material.

Preferably, the portions folded over do not define a base greater than the cross-sectional area of the pipe. In this way, economical use of the foldable material can be achieved.

Conveniently, the axial length of the portions folded over is selected to provide a symmetrical fold pattern about two perpendicular axes in the plane of the base. By providing a symmetrical fold pattern the manner of fold applied to each side for forming the base is unified so that the folding of the foldable material to produce the mould is simplified.

Preferably, the base includes folds extending fromeen the centre of the end of each side to extend to the edges defining the sides at the other end of the respective portions. By having the fold extending from the centre of each side a simplified fold pattern is again achieved.

Preferably, the axial length of the portions are selected so that the folds extending from the centre of the end of each side correspond to the vertice of the base. Consequently, simplified folding of the base is provided. Furthermore, since the mould does not require to take the weight of the liquid bitumen during packaging it is not important that the fold pattern ensures a sealed base. Indeed, this aspect applies to all the aforementioned moulds embodying the invention.

Since the bitumen subsequently solidifies so that the mould is thereafter effectively only packaging, it is not important that the base be able to take the weight of the solidified or liquid bitumen.

In one embodiment, the internal surfaces of the flaps formed by the folds of the said portions are glued together. In this way, if desired, the moulds can be preformed.

In another preferred embodiment an even number of sides are provided and an axially aligned internally facing fold is formed along the centre of at least one pair of oppositely lying sides. By having these internally facing folds, the mould can be flattened in a space saving manner.

Alternatively, where the number of sides is odd, an axially aligned internally facing fold can be formed along a centre of at least one side. Once again this allows the folding flap of the mould in a space saving manner.

Preferably, the mould has six sides and the material has a siliconized internal surface.

According to a further aspect of the invention, there is provided a method of forming a mould for bitumen or the like, comprising the steps in any order of: a) joining together opposite sides of a rectangular or square piece of foldable material to form a pipe; b) forming folds in the material whereby the pipe formed therefrom has three or more sides; c) forming folds in one end portion of each side whereby the end portion is capable of being folded substantially perpendicular to the axis of the pipe formed from the material to provide a substantially flat and complete base.

Consequently, it is possible to form a mould for bitumen or the like which only requires simple erection by folding together. There is no requirementfor any physical attachment between component parts.

Preferably, the axial length of the portions folded over is salected to provide a symmetrical fold pattern about two perpendicular axes in the plane of the base.

By providing a symmetrical fold pattern the step of folding the end portion is considerably simplified.

Conveniently, the axial length of the portion folded over is arranged such that the fold length corresponds to the vertice of the base. This is a particularly economical form of the method since although a completely sealed base is not achieved, this is not of great significance since the bitumen poured into the mould subsequently would solidify and effectively seal the base prior to extensive leakage.

According to a still further aspect of the invention, there is provided a method of casting bitumen orthe like including the steps mentioned above, and further including the steps of: d) forming the base of the pipe; e) standing the pipe on the base to form a free standing mould; f) casting bitumen or the like into the mould.

Consequently, the invention provides a cheap, economical and quick method of producing and packaging bitumen since the step of forming the mould and erecting it is considerably simplified compared with the above, hitherto known prior art.

An example of the invention will now be described with reference to the accompanying drawing in which :- Figure 1 is an oblique view of the erected mould.

Figure 2 illustrates a view of the base of the mould shown in Figure 1.

Figure 3 illustrates an end view of the mould shown in Figure 1, in its flattened state.

Figure 4 illustrates a plan view of the mould shown in Figure 1 in its flattened state.

Figure 5 illustrates a view of a base of a further mould embodying the invention.

Figure 6 illustrates a side view of the mould shown in Figure 1 in its flattened state.

Referring to the drawings, a mould 10 comprises a rectangular sheet of bendable material, for example, siliconized brown paper, which is formed into a pipe by joining together opposite sides of the sheet at a seam 13. This paper is also known as Kraft Liner board. The pipe so formed is folded to form a hexagon having six sides 1 to 6. An end portion of length L of each side is folded to define an externally facing fold 14. The end portion of each side is folded to have internally facing folds 12, 13 extending from the central end of each side to the edge defining that side a length L from the end of the side as shown in Figure 4.

It will apparent that the folds can be supplied in different orders and prior to assembly of the tube itself.

The length of the end portion L is selected so that the lengths of the folds 12 and 13 for each side correspond substantially with the vertice of the base formed as shown in Figure 2. Therefore, when the mould is erected, each side is folded toward the tube axis and flaps 15 are formed which can be folded over to produce a substantially flat and substantially complete base for the mould 10.

Consequently, by simply forming a tube out of a rectangular piece of bendable material and applying the above described folds thereto a self-standing mould can be produced. This mould can than be placed on a flat surface, for example, a pallet, and filled with liquid bitumen. Although the base of the mould is not necessarily completely sealed, the liquid bitumen will solidify onto the base and thereby seal it. Accordingly, the formation of the mould requires only a single sheet of material and the erection of the mould can be achieved by simple folding without resort to complex assembly apparatus. Furthermore, the mould so formed can be lain flat allowing simple transport of the moulds.In order to further reduce the area of each flattened mould, further internally facing folds 6,7,9 and 11 can be formed as shown in Figure 1 so that the mould can be concertinered as shown in Figure 3.

Figures 5 and 6 illustrate an alternative form of folds for the base. In this case the fold length 20 on the base extends from the sides 1 to 6 defining the base to cross an axially aligned line 8 central of each side, whereas in Figure 2 these folds meet the axially aligned line at the end of the portion L. Thus an extra section is formed which is divided by the fold into a major and minor section. As illustrated, the major section is removed so that all the minor portions interlock to allow easier erection of the mould.

Conveniently, the moulds are sized so that the weight of solid bitumen that can be cast into the mould is of the order of 10 to 40 or 45 Kilos.

Although Figures 1 to 4 illustrate a mould having six sides, it will be apparentthata mould can be constructed with three or more sides. In addition, although the folds shown in Figure 2 are arranged to produce a symmetrical pattern, this is a convenient form of the invention which allows optimum usage of the bendable material.

Consequently, other shapes and folds embodying the present invention can be constructed as would be apparent to a person skilled in the art.

A particular advantage of the invention is that the base is formed just by folding in the sides of the mould to provide a free-standing mould. In addition, the base is constructed to be substantially flat and does not need to be load-bearing, since once the bitumen or the like has set solid the mould function is transferred to being a package for the bitumen.

It will be apparentthat although thefolds have been described and illustrated for forming a base, similar folds can be formed so that a top for the mould can be produced. In this way afterfilling with bitumen, the top can be formed. Consequently, a completely packaged block of bitumen is formed so that water penetration into the bitumen is reduced and therefore water does not get into the bitumen when it is subsequently heated back to a liquid state.

Claims

1. A mould for bitumen or the like comprising a length of foldable material folded into a three or more sided pipe with a portion at an end of each side folded over to provide a substantially flat and substantially complete base, whereby the pipe can stand substantially vertically when placed on the base.

2. A mould as claimed in Claim 1 wherein the portions when folded over define a base not greater than the cross-sectional area of the pipe.

3. A mould as claimed in Claim 2 wherein the axial length of the portions folded over is selected to provide a symmetrical fold pattern about two perpendicular axes in the plane of the base.

4. A mould as claimed in Claim 3 wherein the base includes folds extending from an axially aligned line central of the side to the edges defining that side at the end of the portion forming an edge of the base.

5. A mould as claimed in Claim 4wherein the folds extend from the centre of an end of each side.

6. A mould as claimed in Claim 4wherein the folds extend beyond said axially aligned line to the end of the respective side to define a flange.

7. A mould as claimed in Claim 4, 5 or 6 wherein the axial length of the portions are selected so that the folds extending from the axially aligned central line of each side correspond to the vertice of the base.

8. A mould as claimed in Claim 7 wherein internal surfaces of flaps formed by the folds of said portions are glued together.

9. A mould as claimed in any one of Claims 3 to 7 wherein an even number of sides are provided and an axially aligned internally facing fold is formed along the centre of at least one pair of opposite lying sides.

10. A mould as claimed in any one of Claims 3 to 7 wherein an odd number of sides are provided and an axially aligned internally facing fold is formed along the centre of at least one side.

11. A mould as claimed in any preceding Claim having six sides.

12. A mould as claimed in any preceding Claim further including a portion of the pipe remote from the base having folds for folding to provide a substantially flat and substantially complete top.

13. A mould as claimed in Claim 12 wherein said top corresponds to a base of a mould as claimed in any one of Claims 2 to 7.

14. A mould as claimed in any preceding claim wherein the said material has a siliconized surface.

15. A mould as claimed in any preceding claim being a bitumen mould.

16. A method of forming a mould for bitumen or the like, comprising the steps in any order of: a) joining together opposite sides of a rectangular or square piece of foldable material to form a pipe; b) forming folds in the material whereby the pipe formed therefrom has three or more sides; c) forming folds in one end portion of each side whereby the end portion is capable of being folded substantially perpendicular to the axis of the pipe formed from the material to provide a substantially flat and complete base.

17. A method as claimed in Claim 16, wherein, in step (c), the axial length of the portions folded over is selected to provide a symmetrical fold pattern about two perpendicular axes in the plane of the base.

18. A method as claimed in Claim 17, wherein, in the step (c), folds are formed to extend from an axially aligned line central of each side to extend to the edges defining that side at the end of the portion forming an edge of base, the axial length of the portion folded over being selected so that the length of the last mentioned folds corresponds to the vertice of the base.

19. A method of casting bitumen or the like including the steps of any one of Claims 16 to 18, and further including the steps of: d) forming the base of the pipe; e) standing the pipe on the base to form a free standing mould; f) casting bitumen or the like into the mould.

20. A method as claimed in Claim 19 including the step of forming folds in the other end portion of each side to provide a top corresponding to a base of the mould formed according to any one of Claims 16 to 18, and forming the top after step (f).

21. A method of casting bitumen orthe like comprising the steps of: a) forming a mould according to any one of Claims 1 toll; b) standing the pipe on the base to form a free-standing mould; c) casting bitumen or the like into the mould.

22. A mould for bitumen or the like substantially as herein described with reference to the accompanying drawings.

23. A method of casting bitumen orthe like substantially as herein described with reference to the accompanying drawings.