Fire protection for pipes

Abstract

A fire protection product for use as fire protection of a pipe (10), comprising an active layer (11) of a material containing an active substance which, when subjected to heat, expands and undergoes one or more endothermic reaction processes, the active layer (11) enclosing the pipe (10) on at least a length of the pipe to be protected; a plurality of distance pieces (12) extending a distance outwardly from the active layer (11); and an outer tubular cladding (13) supported by the distance pieces (12) and enclosing the pipe (10), the active layer (11) and the distance pieces (12). The active layer (11), the distance pieces (12) and the outer tubular cladding (13) define a space (15) with a volume, which can accommodate the active substance (11) after the active substance (11) has expanded. The active substance can be rubber based or polymer based.

Claims

1. A fire protection product configured to protect a pipe, the fire protection product comprising: an active layer of a material comprising an active substance which, when subjected to heat, expands and undergoes an endothermic reaction process, the active layer enclosing the pipe on at least a length of the pipe to be protected, a plurality of distance pieces extending a distance outwardly from the active layer, and an outer tubular cladding supported by the distance pieces and enclosing the pipe, the active layer and the distance pieces, wherein the active layer, the distance pieces and the outer tubular cladding define a space with a volume, which can accommodate the active substance after the active substance has expanded, wherein the space defines a draining path for draining of water, wherein the plurality of distance pieces extend circumferentially around the active layer and have gaps aligned in an axial direction of the pipe so as to define the draining path, and wherein a longitudinally extending part of the draining path comprising the gaps extends along at least a part of a downwardly facing side of the length of the pipe to be protected, when the fire protection product is in use.

2. The fire protection product according to claim 1, wherein the longitudinally extending part of the draining path comprising the gaps is straight.

3. The fire protection product according to claim 1, wherein one or more draining holes are provided in the outer tubular cladding and said one or more draining holes are configured to drain water from the draining path through the one or more draining holes.

4. The fire protection product according to claim 3, wherein each draining hole of the one or more draining holes is closed with a removable plug.

5. The fire protection product according to claim 1, wherein the active layer is water impermeable.

6. The fire protection product according to claim 1, wherein the active substance is halogen free.

7. The fire protection product according to claim 1, wherein the active substance is fibre free.

8. The fire protection product according to claim 1, wherein the active substance releases no corrosive gases or significant smoke production when heated.

9. The fire protection product according to claim 1, wherein the active substance will, at a first elevated temperature, swell and fill the void spaces generated by the distance pieces and, secondly, undergo a first endothermic process during, whereby water is released and evaporated.

10. The fire protection product according to claim 9, wherein the active substance will, at a second elevated temperature higher than the first elevated temperature, undergo a second endothermic process during which a physically and thermally stable fire barrier is created.

11. The fire protection product according to claim 1, wherein the active substance is a thermoplastic compound containing inorganic fillers in a binder composed of a copolymer.

12. A pipe comprising the fire protection product according to claim 1.

13. The pipe according to claim 12, further comprising a layer of thermal insulation material on the outer tubular cladding.

14. The fire protection product according to claim 1, wherein the active substance is a thermoplastic compound containing inorganic fillers in a binder composed of an ethylene copolymer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The fire protection product according to the invention will now be described in more detail with regard to the accompanying figures. The figures show one way of implementing the present invention and is not to be construed as being limiting to other possible embodiments falling within the scope of the attached claim set.

(2) FIG. 1 is a longitudinal section through a section of a pipe with a fire protection product according to the invention; and

(3) FIG. 2 is a cross section through the pipe in FIG. 1 taken as indicated by the arrows A-A.

DETAILED DESCRIPTION OF THE DRAWINGS

(4) In FIG. 1 is shown a section of a pipe 10, e.g. a steel pipe used for conducting hydrocarbons. On the outer surface of the pipe 10 is an active layer 11 of a material containing an active substance which, when subjected to heat, expands and undergoes an endothermic reaction process. The active layer preferably contains a polymer-based or rubber-based material and encloses the pipe on at least a length of the pipe to be protected against fire. A preferred material is the above-identified FAVUSEAL NKX-6174. A plurality of distance pieces 12, preferably of the same material as the active layer 11, are arranged on the outer side of the active layer 11 and extend a distance outwardly from the active layer. The distance pieces should preferably be made of the same material as the active layer in order for the void space created by the distance pieces to be 100% sealed via the swelling effect recognized by the first endothermic reaction process. Such distance pieces made preferably of the same material as the active layer will not cause any adverse effects by combining different technologies, as they are compatible. The distance pieces 12 support an outer tubular cladding 13, e.g. of metal such as steel, and the active layer, the distance pieces and the outer tubular cladding define a space 15 with a volume.

(5) When subjected to heat such as a hydrocarbon fire or a jet fire, the active layer 11 will first expand into the space. The preferred material, FAVUSEAL NKX-6174, will expand to approximately two times its original volume, and the volume of the space is dimensioned to accommodate the active substance after the active substance has expanded, so that the active substance can expand fully and fill the space 15. In the expanded state, the FAVUSEAL NKX-6174 has a thermal conductivity of about 10% of the thermal conductivity in the non-expanded state and therefore acts as an insulating layer later in a fire scenario.

(6) Humidity in the space 15 may arise from water ingress via leakage in the joints of the tubular metal cladding, or as a result of condensated water resulting in temperature differences between the fluid flowing inside of the pipe and the ambient temperature, and will form liquid water. The space 15 in itself defines a draining path for draining of water out of the product. As best seen in FIG. 2, each of the plurality of distance pieces 12 extends circumferentially around the active layer 11 and have gaps 16 aligned in the axial direction of the pipe so as to define the draining path extending in the longitudinal direction of the pipe 10. As seen in FIG. 1, a longitudinally extending part of the draining path 15,16 comprising the gaps 16 extends along a substantial length of a downwardly facing side of the length of the pipe 10 to be protected, when the fire protection product is in use. This longitudinally extending part of the draining path 15,16 comprising the gaps 16 may be straight.

(7) The outer cladding 13 preferably has one or more draining holes 17 for draining of water from the draining path through the draining holes 17. Each draining hole 17 is closed with a removable plug 18. Preferably, the plugs 18 are self-locking drain plugs that, in case of fire, will seal off the opening via an intumescent material inside the drain plug, such as a graphite-based high intumescent material, or any other expanding material fit for the purpose in order to seal off the drain plugs, consequently, maintaining the integrity of the invention when exposed to a fire.

(8) The above-described structure with the active layer 11, the distance pieces 12 and the outer tubular cladding 13 constitute a fire protection of the pipe 10.

(9) If desired, a layer of thermal insulating material 19, not necessarily with any fire resistance at all, can be applied to the outer surface of the outer tubular cladding in order to yield both thermal and fire protection 13. Suitable thermal insulating materials include mineral wool products such as ISOVER ULTIMATE from SAINT-GOBAIN ISOVER and similar products yielding thermal insulation.

(10) Although the present invention has been described in connection with the specified embodiments, it should not be construed as being in any way limited to the presented examples. The scope of the present invention is set out by the accompanying claim set. In the context of the claims, the terms comprising or comprises do not exclude other possible elements or steps. In addition, the mentioning of references such as a or an etc. should not be construed as excluding a plurality. The use of reference signs in the claims with respect to elements indicated in the figures shall also not be construed as limiting the scope of the invention. Furthermore, individual features mentioned in different claims, may possibly be advantageously combined, and the mentioning of these features in different claims does not exclude that a combination of features is not possible and advantageous.