GB2251026A

GB2251026A - Fixing heat insulating jackets to containers

Info

Publication number: GB2251026A
Application number: GB9123124A
Authority: GB
Inventors: Hans Viessmann
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-11-06
Filing date: 1991-10-31
Publication date: 1992-06-24
Also published as: FR2668812B3; ES1019909Y; IT221993Z2; GB9123124D0; FR2668812A3; ITMI910953V0; DE4035137A1; ES1019909U; DE4035137C2; CH683711A5; BE1004783A6; ITMI910953U1

Description

2,Z,31020 SYSTEM FOR FIXING HEAT INSULATING JACKETS TO CONTAINERS The

invention relates to a system for fixing heat insulating jackets to containers, in which the abutting edges of the heat insulating jacket are held together by means of inter-connectable sheet metal strips extending along the abutting edges and in this way the heat insulating jacket is held on the object to be insulated.

In order to secure a heat insulating jacket, generally consisting of glass wool or the like lined on one side with thin spun glass fabric, to containers, it is known to fix the two ends of the jacket together by means of gripping hooks, with clamping springs arranged between two gripping hooks which are anchored in the ends. Since this does not allow the two ends of the jacket to abut closely on each other, the two ends of the jacket are overlapped, but inevitably an open wedge is produced between the overlap area and the wall of the container to be insulated, allowing air to circulate which, again inevitably, results in loss of heat. Quite apart from this, heat insulation of this kind does not look satisfactory. It is also known to provide a number of bandages in the form of strips having suitable closure elements around the jacket which has been put into position. Since the ends of the jacket are not secured, again it is essential to provide an overlap, since the tensioning of these bandages will cause the intermediate areas of the edges of the jacket to bulge to a greater or lesser extent, again producing open wedge-shaped gaps in the area where the ends of the jacket meet. Moreover, this method of heat insulation means that the jacket to be put into position has to be suitably oversized so that the jacket ends can be overlapped. Admittedly, this oversizing is not of any great importance for one insulating jacket but when large numbers are produced this oversizing adds up to a substantial amount.

Apart from the prior art mentioned above, for which there are no printed specifications as evidence, it is known from US Patent 3030250, to enclose the insulating jacket used for pipe insulation with a wire mesh having two sheet metal strips which are provided on the one hand with slotted eyelets and on the other hand with bendable tabs which can be inserted in these eyelets. Apart from the fact that, as a result, the metal strips are not identical and handling is difficult, further tightening is not possible. A fixing system according to DE-OS 1525497, which comprises a sheet metal sheathing the opposing curved edges of which are held together by means of an overlappable securing strip, is extremely complex. Sheet metal sheathings which are, furthermore, provided on both sides of the heat insulating material, are also known from British Patent 772759, in which the edges -of the sheet metal sheathings are additionally provided with perforated metal strips attached by wire. Equally complex is the pipe insulation according to British Patent 736267, in which the thin sheet metal surrounding the insulating material is repeatedly bent and folded in order to form the connecting ends and strips which can be secured with wire. Insulation according to French patent 2479409 is of similar construction. Insulation held together merely by hooks and ties is known from British Patent 112147 and US patent 2514170 and insulation secured only with small clamping brackets is known from US Patent 2160009.

The aim of the invention is provide a system for fixing heat insulating jackets to containers which is reasonably easy to manufacture, fit and close up without having to take into account precise measurements, and by means of which the soft ends of the jacket are simultaneously bound and reinforced, and which also makes it possible to secure the edges of the jacket close together, without any gussets or open spaces, whilst avoiding the need for overlap allowances on the corresponding jacket tailored to the shape of the container.

According to the present invention there is provided a system for fixing heat insulating jackets to containers, in which the abutting edges of the heat insulating jacket are held together by means of interconnectable strips extending along the respective abutting edges whereby the heat insulating jacket may be held on the object to be insulated, wherein the strips are of identical form and structure and are secured to the edges of the heat insulating jacket, and which are provided, on their longitudinal edge remote from the abutment edge, with jacket fixing means and on their surfaces with a plurality of hooks directed away from the abutting edge and capable of being tensioned by means of at least one tying cord or by means of resilient clamping rings.

The fixing system is simply fitted to the suitably dimensioned jacket shape with its two strips, preferably metal, at the ends of the jacket shape. The two strips may already be connected to each other by means of connecting strips which extend longitudinally of the jacket on the spun glass fibre side thereof. The method of attaching the two strips to the jacket will be explained more fully hereinafter. The jacket is then placed in this prepared state around the housing in question, the two strips fixed to the edges of the jacket moving into a parallel position at a certain spacing from each other. Since the jacket is cut to length to fit precisely around the circumference which it has to enclose, the two cut surfaces of the ends of the jacket abut precisely on each other, and this "insulating package" which is already to some extent pre-wrapped then only has to be secured by engaging the hooks of the two strips, which face away from the abutting edge, as will be explained hereinafter.

Since the edges of the heat insulating jacket are reinforced by the metal strips, the edges cannot bulge even during the tightening process. The connecting strips are somewhat shorter than the length of the blank for the jacket by an amount corresponding to the width of the metal strip and the recessing of the metal strip relative to the actual cut edges of the jacket.

Advantageously, wires of suitable material simply dotted onto the metal strip by spot welding may be used for the connecting elements.

As for the jacket fixing elements in the fixing system, these may be constructed as tabs provided on the longitudinal edge of the metal strips away from the impact edge or as fishplates punched out of the surface of the metal strips up to a connecting edge. Since these tabs or fishplates cannot readily be punched through the spun glass fibre, the spun glass fibre has to be pre-slotted at suitable points. However, this can advantageously and easily be avoided by cutting or stamping out these tabs or fishplates in the form of acute angled triangles, so that it is readily possible to stab the tabs or fishplates into the spun glass fibre and the glass wool below it without having to pre-slit the spun glass fibre. The metal strips are then easily fixed to-the edges of the jacket by means of a suitable tool with which the pushed-in tabs or fishplates are bent counter to the direction of pulling.

The connecting or tying of the two parallel-running metal strips may be done in various ways. Either, small clamping rings of a suitable resilient material may be braced between two hooks, or one or two tying cords may run continuously, e.g. in a zig zag pattern, through all the hooks in both sheet metal strips, going from one to the other alternately, in which case the end or ends of the tying strips are suitably secured to one and/or other metal strip. Expediently, only one tying strip of suitable length is used, which is advantageously fixed beforehand to one or other metal strip and is thus an integral part of the fixing system. The identical metal strips formed of thin, galvanised or aluminium-coated sheet metal are usefully formed with all the hooks, jacket fixing means and optionally reinforcing members from a single sheet metal blank.

In a second embodiment, no connecting strips are provided on the two metal strips, thus simplifying the storage, transportation and handling of the fixing system. Whereas in the first solution the jacket does not have to absorb any circumferential forces, in the second solution the strength of the laminated layer of fabric is put to use, although this does require the metal strip to be securely attached to the jacket edges, i.e. a fixing system of this kind absolutely requires an insulating jacket with a layer of fabric laminated thereon.

Some embodiments of the invention will now be described by way of example and with reference to the accompanying drawings in which:

Fig. 1 is a plan view of the two identically shaped metal strips with the associated connecting elements; is a section along the line II-II of a metal strip according to Fig. 1; is a section along the line III-III through a sheet metal strip according to Fig. 1; is a fixing system in place on a heat insulating jacket shown in section; is a view of the fixing system with the total heat insulating wrapper, again in the position of use on a housing which is to be insulated; is a front elevation of a particular embodiment of the jacket fixing elements; Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 is a section through the ends of the jacket belonging to the fixing system according to claim 2; and Fig. 8 is a section on a much enlarged scale of a particular embodiment of the metal strips.

As can be seen from Figs. 1 and 4, the fixing system consists of two metal strips 1 of identical shape and construction which are connected to each other by means of at least two flexible connecting strips 2 attached to them in the form of wires 21, each metal strip 1 being provided on its longitudinal edge 3, away from the contact edge, with jacket fixing elements 4 and on its surface 11 with a plurality of hooks 5 facing away from the contact edge. The metal strips constructed in this way are set back somewhat relative to the abutting surfaces 11 and, as shown in Fig. 4, are arranged on the ends 10 of the jacket blank and secured thereto. They are secured to these ends 10 by the jacket fixing means 4, which are conveniently cut in the shape of an acute-angled triangle as shown in Fig. 6. After the lining of spun glass fabric 12 has been pierced, these fixing means 4 are folded round, as shown by broken lines in Fig. 4, using a simple tool, a task which is easily carried out in view of the softness of the glass wool which forms the heat insulating jacket 9. It is essential that these fixing means be folded round counter to the direction of clamping. Having been prepared in this way, the entire heat insulating jacket 9 including the fixing system mounted thereon as described above is placed around the container or housing in question as shown in Fig. 4, so that the two abutting surfaces 11 of the heat insulating jacket 9 fit closely against one another. Once this- is done, the two metal strips 1 merely have to be joined together with some tension, which, as mentioned above is carried out using a suitable tying cord 8 which runs from hook to hook as shown in Figs. 1 and 5, for example, and is then 7 - fixed with its free end to one or other metal strip by suitable means, e. g. by simply winding it several times round a hook 5 at the end of a metal strip. The clamping forces act from one metal strip 1 through the connecting strips 2 to the other metal strip 1, without the participation of the heat insulating jacket 9, and from this second metal strip 1 they are returned to the other metal strip via the tying cord 8 or flexible clamping rings 81 (shown by broken lines in Fig. 1).

In the embodiment according to Fig. 7, the situation is different in that the spun glass fabric lining 12 of the jacket 9 itself is involved in the transfer of clamping forces from one metal strip 1 to the other. However, this requires particularly secure and tear-resistant fastening of the metal strips to the spun glass fabric lining 12, which is absolutely essential in this case, and which contains suitably spaced holes registering with holes 13 in the metal strips 1, so that the entire structure, as shown by way of example, can be riveted firmly together with rivets 14 and rivet washers 15 placed below the fabric lining 12.

Instead of using suitable rivets 14, however, it is advantageously possible according to Fig. 8, particularly as the metal strips 1 are made of relatively thin sheet metal, to construct these strips with a view to producing the jacket fixing means 4 so that these means 4 are formed from suitable perforated discs 12 which can be riveted to the necked portions 16. However, instead of individual discs 17, perforated metal strips 171 the length of which corresponds to the metal strips 1 may also be provided. The only essential feature in the embodiments according to Figs. 7 and 8 is that the spun glass fabric lining 12 should be securely attached at the rivet points so as to prevent it being pulled in or out. Since this does away the need for connecting strips 2, this embodiment is more user- - 8 friendly than the one illustrated in Figs. 1-6.

Claims

1. System for fixing heat insulating jackets to containers, in which the abutting edges of the heat insulating jacket are held together by means of interconnectable strips extending along the respective abutting edges whereby the heat insulating jacket may be held on the object to be insulated, wherein the strips are of identical form and structure and are secured to the edges of the heat insulating jacket, and which are provided, on their longitudinal edge remote from the abutment edge, with jacket fixing means and on their surfaces with a plurality of hooks directed away from the abutting edge and capable of being tensioned by means of at least one tying cord or by means of resilient clamping rings.

2. A fixing system as claimed in claim 1 wherein the strips are connected to each other by means of at least two flexible connecting strips attached thereto.

3. A fixing system according to claim 2, wherein the strips are metal and the connecting strips take the form of wires spot-welded onto the metal strips.

A fixing system according to claim 1, 2 or 3, wherein the jacket fixing means are constructed as tabs arranged on the longitudinal edge remote from the abutment edge or as fishplates stamped out of the surface of the strip up to a connecting edge.

5. A fixing system according to claim 4, wherein the tabs or fishplates are cut out in the form of acuteangled triangles.

6. A fixing system according to claim 1, wherein the jacket fixing means consists of holes, rivets and rivet - washers arranged in the strips.

7. A fixing system according to claim 1, wherein the jacket fixing means are formed from holes provided with necked portions and suitable perforated discs or sheet metal strips capable of being riveted to the necked portions.

8. A fixing system according to any preceding claim wherein a tying cord is secured to at least one of the strips.

9. A fixing system according to any preceding claim wherein each strip together with all the hooks is formed is from a single sheet metal blank.

10. A fixing system according to any preceding claim wherein each strip is provided with a reinforcing configuration.

11. A fixing system substantially as hereinbefore described with reference to Figs. 1 to 6, or Fig. 7 or Fig. 8, of the accompanying drawings.

12. The use of the fixing system according to any of claims 1 to 11 for boiler housings or domestic water tanks.