The invention refers to a system consisting of a pipe for the through flow of warm up to hot liquid or gaseous media, a heat insulating pipe shell surrounding the pipe, having an abutting face and being made of a heat insulating material, especially of mineral wool, preferably stone wool and an outer cladding, preferably made of a water-/vapor-tight material like a fiberglass reinforced polyester mat, and a sealing element provided in front of the abutting face of the pipe shell and thereby covering the abutting face of the pipe shell. Furthermore the invention relates to a sealing element for an arrangement at an abutting face of a pipe shell made of a heat insulating material, especially of mineral wool, preferably stone wool, and surrounding a pipe for the through flow of warm up to hot liquid or gaseous media, thereby covering the abutting face of the pipe shell.

It is well known to use insulation elements for pipe work consisting of an insulation layer and an outer cladding. Furthermore, it is well known to use a water tight outer cladding made of a fiberglass reinforced polyester mat which initially is positioned between two sheets of film that are removed during application of the mat to the outer surface of the pipe shell. The cladding contains resins, fiberglass and special fillers and is ready to use. Unprocessed it is soft and malleable. In this state the cladding can be cut or trimmed into any shape which makes it easy to apply to the insulation layer. The fiberglass reinforced polyester mat subsequently cures under the influence of ultraviolet (UV) light. After curing the cladding is absolutely watertight and is able to give optimal mechanical protection. The cladding made of a fiberglass reinforced polyester mat is with respect to the mechanical characteristics comparable to a cladding made of sheet metal.

Pipes of a system according to the invention and according to the prior art are often used for the through flow of warm up to hot liquid or gaseous media, e.g. as thermal oil pipe lines. There is currently a risk of self-ignition if the flammable fluid is getting into an open celled insulation, such as if mineral wool is used as a material for the pipe shell. On the other hand it is necessary to insulate abutting faces of the pipe shell surrounding the pipe. For this purpose normally sealing elements are used. Such a sealing element is for example known from JP 2016-044750 A. This sealing element is made of a two-part end cap for closing the end of pipe insulation. The two-part end cap is shaped with a S-like cross section thereby having a first flange being in contact with the outer surface of the pipe and a second flange erecting in the opposite direction of the first flange and being in contact with the outer surface of the pipe shell. Adhesive layers may be provided between the end caps and the pipe and the outer cladding, respectively.

Furthermore, US 5,503,198 shows an end cap being preferably made of a punched aluminum blank. The end cap may be secured to the pipe insulation by a tie. The end cap according to this prior art is shaped like a frustum. The end cap has a central aperture of a diameter only slightly larger than that of the pipe. Furthermore the end cap has a pre- insulation engaging collar portion which will readily fit over the pre-insulation end of the pipe shell. From the collar, the end cap has a necked-down or cone portion and also has an overlapping portion to assure a complete seal about the pre-insulation end of the pipe shell. Nevertheless, because of the shape of the end cap there is a hollow space between the pipe shell and the end cap, having disadvantages with respect to thermal insulation.

A further embodiment of an end cap is known from DE 41 06 372 A1. This end cap is made of metal and consists of two pieces that are interconnected by a hinge. A separate ring-shaped element consisting of two half-parts is provided between the end cap and the pipe.

Therefore, end caps for pipe sections are well-known. Nevertheless the thermal characteristics of these end caps are not satisfying as these end caps are heated up by a hot pipe and depending on the temperature outside the pipe and the pipe shell the end caps keep a certain high temperature which is on the one hand dangerous for someone coming into contact with the end cap and is on the other hand of disadvantage as heat from the pipe cannot be reduced sufficiently before it reaches the outer cladding of the pipe shell via the end cap. This is particularly a problem if the outer cladding is an organic mat or sheet which cannot withstand too high temperatures, such as a polyester reinforced mat.

It is one object of the invention to provide a system according to the invention which avoids the before-mentioned disadvantages and which is able to be cooled down sufficiently.

Furthermore it is an object of the invention to provide a sealing element for an - -

arrangement at an abutting face of a pipe shell for surrounding a pipe which avoids the before-mentioned disadvantages, which is easy to produce and which is easy to install.

With respect to the system this object is achieved in that the sealing element is provided with at least one device for reducing the temperature being transmitted via the sealing element from the pipe to the outer cladding and in that the device for reducing the temperature comprises at least one heat sink, preferably at least one cooling fin and/or at least one bar-shaped element erecting from the sealing element being arranged on a surface opposite of a surface being in contacting with the abutting face of the pipe shell. To achieve the before-mentioned object with respect to a sealing element it is provided with at least one device for reducing the temperature being transmitted from the liquid or gaseous media to the sealing element via the outer wall of the pipe and in that the device for reducing the temperature comprises at least one heat sink, preferably at least one cooling fin and/or at least one bar-shaped element erecting from the sealing element being arranged on a surface opposite of a surface intended for being in contacting with the abutting face of the pipe shell.

The device for reducing the temperature comprises at least one heat sink, preferably at least one cooling fin and/or at least one bar-shaped element erecting from the sealing element being arranged on a surface opposite of a surface being in contact with the abutting face of the pipe shell. Thereby the sealing element provided with for example cooling fins has a function of an end cap for pipe insulation shell which on one hand closes the open end of a pipe shell and at the same time ensures that the outer cladding is not exposed to too high temperatures. The cooling of the sealing element is effected by ambient air in combination with the heat sink, especially a cooling fin and/or a bar-shaped element working as a cooling element. Of course, several cooling fins and/or bar-shaped elements can be arranged at the sealing element, preferably erecting parallel to each other in the same direction. The bar-shaped elements and/or the cooling fins can have different dimensions; for example so that the cooling elements of larger dimension are arranged closer to the pipe as cooling elements being arranged with more distance to the pipe, as it is known that the heat radiant is reduced in radial direction of the pipe and/or pipe shell. Therefore larger cooling elements are preferably used in areas with higher temperature as the larger cooling elements are able to absorb more heat energy and because of the larger surface more heat energy can be transmitted to ambient air. The ambient air is thereby the cooling medium.

According to a further feature of the invention the sealing element and/or the device for reducing the temperature is/are made from metal, especially aluminum or stainless steel. These materials have a high thermal conductivity which enables these materials to take over a high heat energy and to transmit the heat energy to ambient air. Furthermore, a sealing element and/or device for reducing the temperature made of this material is rigid and even if these elements are exposed to high temperatures they do not tend to break or to get un-tight. In the same way these materials can withstand high mechanical forces.

According to a further aspect of the invention the sealing element is made from an annular washer, preferably with an L-shaped and more preferably with an S-shaped cross-section, having at least one leg being arranged parallel to the longitudinal axis of the pipe. Especially a sealing element with an S-shaped cross-section has the advantage that one leg can be arranged on the outer surface of the pipe and the second leg can be arranged on the outer surface of the pipe shell or the outer cladding. These legs are preferably used to cover a part of the pipe and/or the outer cladding, thereby being able to take over heat energy from the pipe and furthermore being able to be used for fixing the sealing element to the pipe and to the outer cladding. For example one or more ties can be used for fixing the sealing element to the pipe and the outer cladding. Alternatively and depending on the outer cladding of the pipe shell one or more screws could be used to fix the sealing element at least at the outer cladding. For this purpose the outer cladding needs to have a sufficient thickness and/or a sufficient rigidity. The same is applicable to fixing the sealing element to the pipe.

To simplify the mounting of the sealing element to the outer cladding of the pipe shell and the pipe especially in case of pipes and pipe shells with large diameters it is of advantage to divide the sealing element into two, three or four parts, being preferably of identical shape and being connectable to each other, preferably by using clamping elements, like a bolt and a nut connection and/or at least one tensioning belt. Dividing the sealing element in two or more parts has the advantage that the separate parts have lower weight and can be handled more easily by only one person. Another advantage is that a sealing element being divided in two or more parts can be installed even in cases where it is not possible to move the sealing element in lengthwise direction of the pipe until the sealing element - -

reaches its position at the end of the pipe shell. Therefore, dividing the sealing element in two or more parts has the big advantage that such a sealing element can even be used in cases of refurbishment of a system according to the invention. If there is limited space it might also be easier to mount the a sealing element divided into separate parts.

To achieve a water-/vapor-tight connection a gasket is arranged between an outer cladding of the pipe shell and the sealing element. The gasket may comprise ceramic glass, silicone and/or a compressible material, like mineral wool. A further gasket can be arranged between the outer surface of the pipe and the sealing element and of course both gaskets can be one part or can be connected to each other. The service temperature of such gaskets needs to be higher than the system temperature of the pipe.

The before-mentioned features and advantages of the system are in the same way applicable to the sealing element according to the invention.

The system according to the invention comprises a sealing element which is preferably made of two halves forming an end cap being made for example of stainless steel. Cooling fins can be welded on the surface of the end cap so that ambient air can cool down the end cap as good as possible. The end cap is being mounted on a heat transferring pipe. A connection between the two parts of the end cap is made with bolts and nuts. To achieve a water-/vapor-tight connection, a sealing or a gasket (which can be used up to the system temperature) has to be put between the pipe and the sealing element and between the outer cladding of the pipe shell and the sealing element.

The insulation of the pipe can already be cladded with for example ProRox GRP 1000 from ROCKWOOL Technical Insulation. The connection between the sealing element and the surface of the cladding can be closed with a sealing or gasket which is pressed down by a conventional piece of stainless steel cladding which is fixed with two metal bands.

A further big advantage of the invention is that it can be made water-/vapor-tight also up to very high temperatures. This enables to use the invention in combination with pipes which are carrying flammable fluids at high temperatures (e.g. thermal oil pipe lines). Because there is currently a risk of self-ignition if the flammable fluid is getting into the open celled mineral wool the invention can be used as a system for such thermal oil pipe lines as well - -

as for the industrial sectors, where flammable liquids are carried at a high temperature. The risk of self-ignition can be decreased and for example replace cellular glass as sealing elements at the end of mineral wool pipe shells.

Further features and embodiments of the invention are described in the following with respect to the drawings showing preferred embodiments of the invention, wherein:

Fig. 1 shows a system according to the invention in a partly cut side view;

Fig. 2 shows a first embodiment of a sealing element in a front view;

Fig. 3 shows the embodiment of the sealing element according to Fig. 2 in a side view;

Fig. 4 shows a second embodiment of a sealing element in a front view;

Fig. 5 shows the embodiment of the sealing element according to Fig. 4 in a side view;

Fig. 6 shows an embodiment of the sealing elements according to the Figs. 2 to 5 in a front view;

Fig. 7 shows a second embodiment of a system according to Fig. 1 in a cut side view; Fig. 8 shows a fourth embodiment of a system according to Fig. 1 in a cut side view; and Fig. 9 shows a system according to the prior art.

Fig. 9 shows a system 1 according to the prior art consisting of a pipe 2 for the through flow of warm up to hot liquid or gaseous media, a pipe shell 3 surrounding the pipe 2 and having an abutting face 4. The pipe shell 3 is made of a thermal insulating material like mineral wool. The pipe shell 3 is covered on its outer surface 5 with a cladding 6 which is made of a water-/vapor-tight material like a fiber glass reinforced polyester mat, for example ProRox GRP 1000 from ROCKWOOL Technical Insulation.

In front of the abutting face 4 a sealing element 7 made of cellular glass is arranged - -

thereby covering the abutting face 4 of the pipe shell 3. A gasket may be arranged between the sealing element 7 and the abutting face 4 of the pipe shell 3.

As can be seen from Fig. 9 two pipes 2 are connected via flanges 8 being connected to each other via nuts 9 and bolts 10. As it might be necessary to open the pipe 2 in the area of the flanges 8 a certain distance between the free end of the sealing element 7 and the flange 8 is necessary to be able to remove the bolt 9 which erects through both flanges 8 out of an aperture in the flanges 8.

Fig. 1 shows a system 1 according to the invention. Also here two pipes 2 are connected via flanges 8 each having several apertures being collinear to each other in the two flanges 8 and being provided with bolts 10 and nuts 9 according to Fig. 9 (not shown in Fig. 1 ). The pipe 2 according to Fig. 1 is surrounded by a heat insulating pipe shell 3 made of stone wool. The pipe shell 3 is provided with an abutting face 4 and the outer surface 5 is covered by the cladding 6 made of a fiber glass reinforced polyester mat.

Fig. 1 shows a sealing element 7 according to the invention. The sealing element 7 is made from an annular washer 1 1 with an S-shaped cross-section having two legs 12, 13 being arranged parallel to the longitudinal axis of the pipe 2. The legs 12, 13 are connected via the annular washer 1 1 . Annular washer 1 1 and legs 12, 13 are one piece and are made of stainless steel. Furthermore the annular washer 1 1 is provided with a device 14 for reducing the temperature being transmitted from the liquid or gaseous media to the pipe shell 3 and/or to the sealing element 7 via the outer wall of the pipe 2.

Additionally a gasket 15 surrounds the pipe 2 and is arranged between the leg 13 of the sealing element 7 and the outer surface of the pipe 2. A further gasket 16 is arranged between the leg 12 of the sealing element 7 and the outer surface of the cladding 6. The gaskets 15, 16 seal the abutting face 4 against transmittal of liquid and/or gaseous media to avoid a contact of the pipe shell 3 with such media.

The device 14 for reducing the temperature being transmitted from the pipe 2 to the sealing element 7 is made of two cooling fins 17 being connected to the annular washer 1 1 and surrounding the pipe 3 with a certain distance to the outer surface of the pipe 2. It can be seen that the cooling fins 17 have the same shape and the same longitudinal extent. - -

Figs. 2 and 3 show a second embodiment of the sealing element 7 and this embodiment according to Figs. 2 and 3 shows an annular washer 1 1 being divided into a first part 18 and a second part 19. Both parts 18, 19 are equipped with flanges 20, which are used to connect the two parts 18, 19 via nuts and bolts.

As can be seen from Fig. 3 the two cooling fins 17 have different length whereby the inner cooling fin 17 is longer than the outer cooling fin 17.

Coming back to Fig. 1 the sealing element 7 is connected to the pipe shell 3 via at least one tensioning belt 21 surrounding the sealing element 7 in the area of the leg 12. A further tensioning belt (not shown) can of course be arranged on the outer surface of the leg 13 of the sealing element 7.

The gaskets 15, 16 are made of a layer surrounding the pipe 2 and the pipe shell 3 and may comprise ceramic glass, silicon and/or a compressible material, like mineral wool. Of course several layers can be used being arranged sandwich-like and being made of identical or different materials.

A further embodiment of a sealing element 7 is shown in Figs. 4 and 5. The sealing element 7 according to Figs. 4 and 5 as well as according to Fig. 6 is made of four parts 18, 19 being connected to each other via flanges 20 and bolts 22 and nuts 23. Furthermore, the embodiment of the sealing element 7 according to Figs. 4 and 5 differs from the embodiment according to Figs. 2 and 3 by devices 14 being made of bar-shaped elements 24 erecting from the sealing element 7, namely the annular washer 1 1 and being arranged on a surface opposite of a surface being in contact with the abutting face 4 of the pipe shell 3. As can be seen from Fig. 5 the elements 24 can have different lengths.

A further embodiment of the system 1 is shown in Fig. 7. This embodiment differs from the embodiment according to Figs. 1 to 6 in that the annular washer 1 1 has a diameter which is larger than the diameter of the pipe shell 3 so that the annular washer 1 1 extends over the abutting face 4 in radial direction. To fix such an annular washer 1 1 to the abutting face 4 of the pipe shell 3 a flexible collar 25 is used which is connected to the outer surface of the pipe shell 3 via the tensioning belt 21 while the collar 25 is fixed with its opposite end at - -

the outer edge of the annular washer 1 1. For this purpose the collar 25 has a U-formed bracket 26 being an integral part of the collar 25 and grapping around the annular washer 1 1 . Of course a second tensioning belt can be used to fix the gasket 15 on the outer surface of the pipe 2.

Such an embodiment is useful for a system 1 according to the invention to be used with pipes 2 and pipe shells 3 of different outer diameter. The system 1 according to Fig. 7 can easily be adapted to more or less thick pipe shells 3.

Fig. 8 shows a further embodiment of the system 1 being similar to the embodiment according to Fig. 1 . It can be seen from Fig. 8 that the diameter of the annular washer 1 1 is substantially larger than the outer diameter of the pipe shell 3 which means that the annular washer 1 1 extends radially further out than the outer surface of the pipe shell 3. The annular washer 1 1 is provided with the legs 12 and 13 and it can be seen that between leg 13 and the outer diameter of the pipe 2 two layers of the gasket 15 are arranged. Between the leg 12 and the outer diameter of the pipe shell 3 the gasket 16 is arranged and the annular washer 1 1 is fixed to the pipe 2 with a pipe shell 3 by using the tensioning belt 21 surrounding the leg 12.

If this system 1 has to be adapted to a pipe shell 3 having a smaller or a larger diameter the gasket 16 can be replaced by a gasket 16 having a smaller or a larger diameter. Furthermore the gasket 16 can be made of two layers, possibly made by different materials. The use of compressible gasket material has the advantage that minor differences between the inner diameter of the leg 12 and the outer diameter of the pipe shell 3 with the cladding 6 can be equalized. Likewise, minor differences of the inner diameter of the leg 13 and the outer diameter of the pipe 2 can be equalized by a compressible gasket 15. Furthermore, the system 1 according to Fig. 8 is very flexible because the tightening with respect to the outer surface 5 of the pipe shell 3 can be adjusted by two elements, namely the gasket 15 and the gasket 16. Therefore the sealing element 7 according to Fig. 8 can be used for a great number of pipe shells 3 having different diameters simply by using gaskets with different thicknesses. - -

Reference signs

1 system

2 pipe

3 pipe shell

4 abutting face

5 outer surface

6 cladding

7 sealing element

8 flange

9 nut

10 bolts

1 1 annular washer

12 leg

13 leg

14 device

15 gasket

16 gasket

17 cooling fin

18 first part

19 second part

20 flanges

21 tensioning belt

22 belt

23 nut

24 element

25 collar

26 bracket