It is often necessary to lead pipes or other components through floor or wall sections from one room to an adjacent room, and where, in the adjacent room, there can be requirements for gas and gas tightness, and specific requirements for the temperature. With respect to fire and explosion safety such leading-through operations represent a risk as they weaken the fire and explosion requirements which the floor itself or wall are constructed for. For example, during leading of pipelines through a deck on an oil platform, it is absolutely crucial that the leading- through is safeguarded so that flames and explosions etc cannot spread from one deck to another.

The invention which is described in this patent application is first and foremost aimed at application on platforms, but can be used at any leading-through operation where technical requirements with regard to fire and explosion are made.

There will always be a gap between the outer surfaces of the pipe and the opening in the deck/wall for such leading-through operations with pipes. There are different solutions for insulating such leading-through operations of pipes on the market today, and fig. 1 shows one solution which is marketed by Rockwool. Shown in the figure is a pipe 10 which is led through a deck 12 with associated sheath 14. By sealing the opening, i. e. by insulating the leading-through operation, one will prevent a fire or explosion spreading from one side of the deck to the other.

Fig. 1 shows a sleeve 16 (penetration cover) which seals the gap between the sheath 14 and the outer surface of the pipe 10. This sleeve is produced from a glass fibre cloth and a metal wire netting which is shaped to fit the dimension of the sheath 14 and pipe 10. The materials which are used are in themselves not particularly insulating, and therefore there must be used additional insulating materials 18 between the sleeve 16 and pipe 10. As mentioned, the sleeve 16 is prefabricated in shapes which are made to fit according to the dimensions of the different pipes and guiding pipes. This is a considerable disadvantage compared with the present invention.

Furthermore, the solution is complex to install and the adaptation of the insulating material is particularly time consuming.

Another solution which is used to seal the gap between the pipe 20 and deck 24 is shown in fig. 2. The pipe 20 is encased in an insulating layer 22, and the remaining gap is

sealed by the fitting of a cast plate 26. This solution is therefore very different from the present invention, and a major disadvantage with this solution is that the cast plate cannot be disassembled and used again.

In connection with the novelty assessment carried out in connection with the priority application NO 20002890, the following publications appeared; FR 2494391 describes a flange seal for sealing of the annular space between an inner pipe and an outer pipe. This solution has been known for many years, but in connection with the problem which the present patent is attempting to solve, this solution has not been considered as a real alternative, even if the solution concept itself can appear somewhat similar to the present invention. The solution described in FR 2494391 can in no way provide sufficient guarantee against the transfer and spreading of explosions and fire from, for example, one deck to another.

The basis for the present invention is that one surprisingly has found that a material exists in the form of sheets which ensures a sufficient seal with regard to transfer of gas, explosion and temperature. This material can be sewn to any given shape to cover the gap between a pipe and the leading-through opening itself. This solution represents a considerable advance in relation to the solutions which are available on the market today.

An object of the present invention is thus to provide a solution which is much more flexible than the solutions which are known in the field, and which at the same time maintains, or also improves the insulating characteristics.

An aim of the present invention is therefore to provide a casing which in itself has sufficient insulating characteristics such that a further insulation on the inside of the casing is not required. It must be said

however, that a preferred embodiment comprises such additional insulation.

Furthermore, it is an aim of the present invention that it shall be prefabricated, and that only small adjustments are necessary during installation, so that a quick and effective installation is possible. This is achieved by the device according to the invention being pre-fabricated as universal models, where each of these can be adjusted simply during the installation, within given dimension ranges, to the different dimensions of pipes and the leading-through openings. Furthermore, it shall be possible to use the invention for leading-through operations for components other than pipes.

To ensure such a flexible installation, it is an aim of the present invention that the material from which the casing is produced is flexible.

The above mentioned aims are achieved by using a multi-layer material with a particularly good insulating effect. In this connection the term"insulating effect" means that the material which is being used to provide a sealing between the pipe and the guiding pipe, must be heat resistant and furthermore prevent that heat etc penetrates the material. It is also preferred that the material can withstand a jet fire.

The material which is used, and which is tested in accordance with the invention, is capable of resisting an explosion of 1 bar, and thereafter a temperature of 1100 °C for two hours, without any damage to the material. This is sufficient to prevent a jet fire spreading from one room to another, and it is very surprising that a sheet-formed insulating material can be used for this purpose.

The choice of material is not a part of this invention, but tests have been carried out on a material

which is known from patent application NO 19984893. This material is a so-called multi-layer material and is comprised of an insulating layer and a metal foil, and an outer cloth of a glass fibre or silicon substance.

Preliminary tests with this material indicate that the material satisfies the international requirements. Full- scale tests are presently being carried out. A preferred embodiment of the device according to the invention uses this multi-layer material, but any material which meets the actual fire requirements and which is sufficiently flexible can be used.

Thus, the present invention is characterised in that the casing: a) is made out of a material which demonstrates resistance to penetration by heat, flames and pressure, for example, a so-called jet fire, and b) is made out of a material which is sheet-formed and sufficiently flexible for it to be cut and sown into the form of a casing, and it thereby can be adjusted to fit the different dimensions of pipes and guiding sheaths without casting.

The present invention will now be described in more detail with reference to the enclosed figures, in which; Fig. 1 shows a prior art solution.

Fig. 2 shows a prior art solution.

Fig. 3 shows a casing according to the invention.

Fig. 4 shows a casing with additional insulation.

Fig. 5 shows a join according to the invention.

The present invention also relates to a method as described in the claims 6-11, and a system as described in the claims 12-16.

The material (for example the multi-layer material described above) is sown into a form, preferably in one piece, so that it can be shaped to a casing 30 in that two sections 40a and 40c (see fig. 5) are secured together. In most cases, the casing is fitted after the pipe 31 is fitted into the guiding pipe opening 32a, and that it will be appropriate to be able to disassemble the casing 30, and this will result in it being possible to open and close the casing 30. This often represents a weakness. To avoid that such a join becomes a weak point, while at the same time fitting and disassembly shall be performed quickly and effectively, the inventors of the present invention have developed a system with flap and double Velcro-locking (described below).

The casing 30 is made with two openings 30a, 30b and the opening 30a is given a dimension somewhat bigger than the outer circumference of the pipe 31, while the other opening 30b is adjusted so that it is somewhat larger than the pipe guiding sheath 32a on the deck 32. The casing 30 is secured to the pipe 31 and the pipe guiding sheath 32a respectively, with, for example, pipe clamps 33. As can be seen in fig. 3, the casing 30 will now seal the gap between pipe 31 and pipe guiding sheath 32a.

The casing can be secured on one or both sides of the deck 32, but in a preferred application of the invention, it is fitted to only the upside of the deck 32, i. e. on the side which is not exposed to fire/explosion.

As mentioned, a preferred solution comprises the casing being used together with additional insulation. Such a system is shown in fig. 4 in which the insulating

materials 50,52 and 54 are arranged between the sheath 32a and pipe 31, externally with respect to the sheath 32a and externally on the pipe 31 itself, respectively. All the insulating material which is used is covered with a substance which prevents moisture seeping into the material. Corrosion, in connection with such pipe leading- through operations, is a well known and serious problem and the present solution represents a considerable advance with respect to solutions known from the prior art as such corrosion prevents the insulation from keeping out moisture.

As mentioned above, a system with a flap and double Velcro-lock is used in a preferred embodiment of the invention. This is shown schematically in fig. 5. The section 40a of the material is shaped with a flap 40b, which the other section 40c can be put into. When the section 40c is put into the flap, the two sets of Velcro 41 will make up a good join. In the join itself, three layers of the multi-layer material are arranged on top of each other. It has been found experimentally that when a Velcro join such as this is subjected to an increase in temperature, a chemical reaction will take place which actually reinforces the join itself. This is a surprising find too.

By using a wide Velcro ribbon, one has the possibility to adjust the dimensions of the opening 30a and 30b so that the casing 30 can be adjusted to different pipe and guiding pipe dimensions. It is preferred that the multi-layer material is sufficiently flexible so that it can be shaped to encase the pipe dimensions down to 50 millimetre in diameter.

With respect to the known solutions which are described in fig. 1 and 2, the casing 30 has according to the invention many advantageous features; it is simple to install/disassemble, i. e., the maintenance on pipes lying underneath is simple to carry out, -it can be pre-fabricated, -it is flexible/pliable, -it can be fitted on the unexposed side (avoid the use of scaffolding), -it is not exposed to corrosion attacks.

This is, as far as we know, the first solution for sealing/insulating pipe leading-through operations in which the insulating characteristics are part of the casing itself, and with respect to the prior art solutions, the solution according to the invention represents a considerable improvement.