DE20011996U1 - Exhaust chimney with ring channel and precipitation barrier - Google Patents

Description

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Manfred Ruhland - DEG-38004 _m y _m

Exhaust chimney with ring channel and precipitation barrier Description

In civil and structural engineering works, free-standing chimneys made of steel or stainless steel are usually used for exhaust gas disposal. Chimneys are particularly well-known that have an internal exhaust pipe that is surrounded by thermal insulation for insulation. As a rule, a ring channel remains free between the outer support pipe and the thermal insulation, which can be used, for example, to remove exhaust air from the boiler room or to supply preheated combustion air for oil or gas burners. It is advisable to protect this ring channel and the thermal insulation from incoming precipitation.

In the chimneys known in the state of the art, a plate in the shape of a mushroom-shaped protruding hat is welded to the head end of the inner pipe. Such constructions may serve their purpose, but they have disadvantages in terms of aerodynamics and aesthetics.

In a mushroom-shaped chimney cap, the air in the ring gap has to overcome the strong frictional resistance of a 180° deflection. This leads to an undesirable reduction in air buoyancy in the ring channel, which may then even have to be maintained using draught fans. In addition, the inevitable turbulence also increases the noise level.

For aesthetic reasons, architects also prefer steel chimneys that do not have such a visually striking attachment at the chimney mouth.

The present invention has for its object to overcome the above-mentioned disadvantages. This is achieved by the chimney arrangement described in claim 1. Advantageous embodiments are specified in the subclaims.

According to the invention, a collecting ring is installed directly above the thermal insulation in the area between the inner and outer pipes, which catches precipitation and allows it to flow out through an opening. This ring is not visible from the outside and therefore does not disturb the overall aesthetic impression. In addition, the installation of the comparatively

An inexpensive collecting ring directly on the inner pipe, particularly if the ring is conical, allows the exhaust and supply air to flow past almost unhindered without any significant friction losses.

Preferred embodiments of the invention are explained in more detail below with reference to the drawings, in which

Figure 1 shows a schematic cross section of a chimney head designed according to the invention;

Figure 2 is a side view of a chimney head with an oblique cut; and

Figure 3 is a side view of a multi-flue chimney arrangement, here with two inner pipes.

The chimney head shown in Figure 1 has an upright outer pipe 10 with an annular head plate 11. Concentric to the center axis of the outer pipe 10 there is an inner pipe 12 of smaller diameter, which is parallel to the outer pipe 10, is open at the top and leaves an annular channel 13 free between the pipes. The outer pipe 10 is open at the top in the area of an annular gap 14 between the head plate 11 and the inner pipe 12. A thermal insulation 15 is attached to the outer wall of the inner pipe 12, which prevents the exhaust air from cooling down and thus maintains the natural convection flow of the hot gases in the inner pipe.

A plate-shaped collecting ring 16 is welded to the outside of the inner pipe 12 above the thermal insulation 15. This catches precipitation that penetrates through the annular gap 14 and allows it to flow into the interior of the inner pipe 12 via openings 17. The precipitation that enters the inner pipe 12 is drained to the outside via a separate precipitation barrier in the base area of the chimney. The annular gap 14 has a smaller outer diameter than the collecting ring 16, so that it overlaps the annular gap area and even precipitation that falls at an angle cannot reach the annular channel 13.

Figure 2 shows a side view of a chimney head which differs from that of Figure 1 in that the head area of the outer pipe 10 is extended by an upwardly open part 18 with an oblique cut. Such a design

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of the outer tube 10 is only possible due to the elimination of the mushroom-shaped chimney cap according to the state of the art and has additional advantages.

The angled cut has a streamlined effect and reduces annoying noise that can be caused by cross-flow of air. In addition, such an arrangement is usually desirable from a design perspective and can be produced economically.

Figure 3 shows a multi-pass chimney in which several (here two) inner pipe structures analogous to Figure 1 are located in an outer pipe 10'. Accordingly, the head plate 11' has several holes which can each accommodate an inner pipe 12a, 12b while forming an annular gap 14a, 14b.

All of the examples have the advantage that all of the fittings are inside the chimney and the chimney diameter does not need to be enlarged at any point. This gives the chimneys a simple appearance on the outside and also protects the fittings against damage during transport, assembly work or other external influences. This means that the fittings can also be made relatively light.

Summary

In a chimney with an outer pipe 10 and an inner pipe 12, which is open at the top in the area of the inner pipe 12 and in an annular gap 14 around it, a collecting ring 16 is welded to the outer wall of the inner pipe 12. This protects the thermal insulation 15 installed between the pipes from precipitation penetrating through the annular gap 14 without the need for a complex chimney attachment and without significantly hindering the air flow in the annular channel 13 between the outer and inner pipes.

Claims (9)

1. Chimney with an outer pipe ( 10 ) and an inner pipe ( 12 ) surrounded by thermal insulation ( 15 ), an annular channel ( 13 ) being provided between the outer pipe ( 10 ) and the inner pipe ( 12 ), characterized in that a collecting ring ( 16 ) is fitted above the thermal insulation ( 15 ), which covers the thermal insulation ( 15 ) and has a drain opening ( 17 ). 2. Chimney according to claim 1 with an annular head plate ( 11 ) surrounding the inner pipe ( 12 ) to form a concentric annular gap ( 14 ). 3. Chimney according to claim 1 or 2, wherein the outer diameter of the annular gap ( 14 ) is smaller than that of the collecting ring ( 16 ). 4. Chimney according to one of claims 1 to 3, wherein the collecting ring ( 16 ) has a plurality of drainage openings ( 17 ) into the interior of the inner pipe ( 12 ). 5. Chimney according to one of claims 1 to 4, wherein the collecting ring ( 16 ) is plate-shaped or truncated cone-shaped. 6. Chimney according to one of claims 1 to 5, wherein the collecting ring ( 16 ) is welded to the inner pipe ( 12 ) at its lowest point. 7. Chimney according to one of claims 1 to 6, wherein the outer pipe ( 10 ) is extended by a part ( 18 ) with an oblique cut. 8. Chimney according to one of claims 1 to 7, wherein the outer tube ( 10 , 18 ) projects beyond the inner tube ( 12 ). 9. Chimney according to one of claims 1 to 8, characterized in that several inner pipes ( 12 a, 12 b) are mounted together in an outer pipe ( 10 ').