GB2243429A

GB2243429A - Liner for a chimney

Info

Publication number: GB2243429A
Application number: GB9107212A
Authority: GB
Inventors: Rene Lajoux
Original assignee: Tubest SA
Current assignee: Tubest SA
Priority date: 1990-04-10
Filing date: 1991-04-05
Publication date: 1991-10-30
Also published as: FR2660729B1; FR2660729A1; GB9107212D0

Abstract

Flexible piping (2) for chimney pipes, of the type made of metallic strips whose interior (2a) and exterior (2b) faces are coated with one (5) or two (5, 6) layers eg epoxy-phenol and polyamide or polyurethane for protection against corrosive agents such as smoke, soot and humidity is covered, at least partially, with an exterior (3) layer eg. aluminium for mechanical protection, for example in the course of installation of the piping in a flue. <IMAGE>

Description

Improvement to Flexible Piping for Chimney Pipes The present invention concerns an improvement to flexible piping for chimney pipes, that is to say to flexible piping of the type made of aluminium alloy or stainless steel strips and more especially of the type described in French patent number 8610124 and its first addition number 90 04592 According to this French patent, in order to reduce the risks of corrosion of the flexible piping by smoke and condensation, at least the interior face of the flexible piping is covered with a layer of material which is insensitive to corrosive agents, such as an epoxy-phenol resin.

According to the first addition to this French patent, in order to overcome the disadvantages inherent in its brittle nature each protective layer of material which is insensitive to corrosive agents is itself coated with a layer of material which is far more flexible, such as a pclyamide such as polyurethane. the presence of which has a self#sealing effect on the resin of the first layer Furthermore, according to a preferred embodiment of this flexible piping, the interior and exterior faces are covered with one or both protective layers.

It will be readily understood that, both in the course of handling these flexible piping and in the course of installing them in a flue, the protective layer(s) the exterior face is greatly at risk of being damaged by scratches or similar. necessitating premature replacement of the pipes formed from this piping.

Even though the interior protective layer(s) are protected from this risk of damage, the exterior layer(s) are not so protected and damage to them may, as with damage to the interior layer(s), cause corrosion of the metallic strips, particularly owing to the presence of accumulated soot in the flue receiving a pipe.

The present invention aims to obviate or mitigate these disadvantages.

According to the present invention there is provided flexible piping of the type made of metallic strip(s) the interior and exterior faces of which are coated with at least one layer for protection against corrosive agents such as smoke soot and humidity, provided with, at least almost entirely, an exterior layer having a mechanically protective effect, made of any suitable material which is capable of resisting the mechanical effects to which it is subjected.

The exterior layer may be made of any suitable material 5 particularly aluminium strips.

The exterior layer may be entirely or partially joined by folded seam to the interior strips. or simply coiled without folded seam join within the interior piping, simultaneously with or subsequently to the latter s assembly by folded seam When the exterior layer is made of aluminium strips or similar joined by folded seam, entirely covering the flexible piping its joining by folded seam may be carried out independently of or simultaneously with tha of the interior flexible piping This interior layer may also cover only the corrugations in the interior flexible piping and not its zones of folded seam joints An embodiment of the present invention will now be described by way of example only with reference to the attached drawing. the single figure of which represents a length of piping for a chimney pipe, in axial view.

The drawing shows a piping formed by simultaneous rolling and folded seam joining of two strips, the internal strip 2 and the external strip 3. Only one section of this flexible piping is shown in the drawing, namely a length corresponding to the distance between two successive folded deam joints 4.

The interior strip 2 is of the type described in the above-mentioned French patent and its first addition; ie it consists of a coated aluminium strip on its interior 2a and exterior 2b faces, and at least one anti-corrosive protective layer 5, composed of a meterial which is insensitive to corrosive condensates and smoke.

Preferably, on this layer 5 there is superposed a second layer 6 made of more flexible material than the layer 5, and functioning as a self-sealing agent for any cracks in the first layer 5.

The protective layers 5 and 6 may be composed of for example a layer of epoxy-phenol resin and of a layer of polyamide or polyurethane.

The presence of the exterior layer 3, which has no protective layer on either of its interior or exterior faces, has the sole purpose of protecting the exterior face of the interior tube 2, and more particularly its exterior protective layer(s) 5 and 6, against the scratches which are capable of damaging it, these scratches being capable of arising not only in the course of its handling at various stages, but particularly when it is installed in a flue.

The exterior layer 3 may therefore be made of any suitable material which is capable of resisting the mechanical effects to which it is subjected, particularly in the course of the pipe's installation. For example, according to a simple embodiment of the invention, it may be made of aluminium strips, like the interior piping 2, but not coated.

It will be readily understood that the presence of the layer 3 ensures very effective protection of the protective layer(s) 5 and 6 covering the exterior face of the interior piping 2 before and particularly in the course of the installation of this flexible piping in a flue which is to receive a pipe, but that after this installation, its presence serves practically no purpose.

The exterior layer 3 of mechanical protection may cover only partially the interior piping 2, whatever its mode of embodiment and its composition. For example it may be applied only over the corrugations and not the join seams 4.

Claims

1. Flexible piping of the type made of metallic strip(s) the interior and exterior faces of which are coated with at least one layer for protection against corrosive agents such as smoke, soot and humidity, provided with, at least almost entirely, an exterior layer having a mechanically protective effect, made of any suitable material which is capable of resisting the mechanical effects to which it is subjected.

2. Flexible piping according to Claim 1, in which the exterior layer for mechanical protection consists of an exterior piping made of aluminium strips, or similar.

3. Flexible piping according to Claim 1 or Claim 2, in which the exterior layer for mechanical protection covers entirely the flexible piping and is made by folded seam joining, independently of the interior piping.

4. Flexible piping according to Claim 1 or Claim 2, in which the exterior layer for mechanical protection covers entirely the flexible piping and is made by folded seam joining, simultaneously with the interior piping.

5. Flexible piping according to Claim 1 or Claim 2, in which the exterior layer for mechanical protection is made by being coiled without folded seam joining within the interior piping.

6. Flexible piping according to any one of Claims 1, 2 or 5, in which the exterior layer partially covers the interior piping.

7. Flexible piping according to Claim 6, in which the exterior layer is applied only to corrugations of the interior piping and not to its seam joints.

8. Flexible piping substantially as hereinbefore described with reference to the accompanying drawing.

9. Any novel subject matter of combination including novel subject matter disclosed in the foregoing Specification or Claims and/or shown in the drawings, whether or not within the scope of or relating to the same invention as any of the preceding Claims.