GB2138916A

GB2138916A - A device for the frontal closure of an annular space

Info

Publication number: GB2138916A
Application number: GB08402166A
Authority: GB
Inventors: Gunther Lassak; Rolf Schicketanz; Reinhold Zimmermann
Original assignee: Deutsche Fibercast GmbH
Current assignee: Deutsche Fibercast GmbH
Priority date: 1983-04-28
Filing date: 1984-01-27
Publication date: 1984-10-31
Also published as: FR2545192B3; NL8304479A; GB8402166D0; FR2545192A3; DE8312557U1

Abstract

To prevent water from entering the annular space between a core pipe 3 disposed concentrically inside a jacket pipe 6 and filled with insulating material 8 e.g. polyurethane foam, said space is closed by an annular disc 1 having a conical inner bore adapted to the outside diameter of the core pipe 3, having two cylindrical portions of which one (4) is adapted to the inside and the other (5) is adapted to the outside of the jacket pipe 6. The portion (4) is subdivided by an annular groove 7 which receives a sealing cord 9 to promote sealing between the disc 1 and the pipe 6. <IMAGE>

Description

SPECIFICATION A device for the frontal closure of an annular space This invention relatesto a device forthe frontal closureofanannularspaceorchamberformed bythe concentric arrangement ofa core pipe or inner pipe disposed inside a jacket pipe or outer pipe.

To insulate a pipe through which a medium flows, it is known to arrange the pipe as core pipe concentri cally inside a jacket pipe and to fill, with insulating material, for example hard polyurethane foam, the annular space which is bounded by the outside of the core pipe and the inside of the jacket pipe. In orderto preventwaterfrom penetrating into the annular space, whereby the action of the insulating material would impaired or the insulating material would even be destroyed, for example where the pipes are laid in the ground, it is necessary to close off or seal the ends ofthe annular space which is filled with the insulating material.Forthis purpose it is known to usethermo plastic shrinkage sleeves which require a processing temperatureofoveri000C.On buildingsites,the effective incorporation of such shrinkage caps or sleeves is difficultand can be madeeven moredifficult byweather influences. Annular space sealings under taken in a place ofmanufacture do not, however, make further sealing work under building site conditions superfluous, since frequently standard pipe lengths sealed off in the place of manufacture have to be shortened on the building site on account of a change in direction or branch-off in the course of the pipeline.

Added to this is the fact that the customarythermo- plastic shrinkage caps or sleeves soften at a core temperature over 60to 80 C and thus the sealing effect is considerably impaired.

An object of the invention is to provide a device, for the frontal closure of an annular space between a core pipe and a jacket pipe, which can be easily installed even under building site conditions and which makes possible an absolutely water-tig ht and also tempera ture-stable closure.

To achieve this object, in accordance with the invention an annular disc is proposed which is provided with an inner bore adapted to the outside diameter of the core pipe and with different cylindrical portions which are adapted to the outside diameter and to the inside diameter respectively of the jacket pipe and of which the portion adapted to the inside diameter ofthe jacket pipe is subdivided by an annular groove.

Because of its design the annular disc in accordance with the invention can, in a simple manner, be slipped onto the core pipe and pressed against the jacket pipe and be bonded with the pipes so that an absolutely water-tightclosure ofthe annular space is brought about. In this respect, the sealing action is additionally improved by a sealing cord which is arranged in the annulargrooveoftheportionadaptedtothe inside diameter of the jacket pipe.

In accordance with a development of the invention, the innerboreoftheannulardisc is conical in configuration and the maximum diameter of the inner bore lies on that side ofthe annular disc which faces the annular space.

Asa result ofthis development, upon being pushed ontothecorepipe,theannulardiscactslikeascraper ring and causes there to arise inside the inner bore cone, from adhesive previously applied to the core pipe, a bead of adhesive which guarantees complete sealing between the core pipe and the annular disc.

Finally, a development of the invention additionally provides for the annular disc to consist of duroplastic reaction resin reinforced with glass fibres.

An annular disc produced from reaction resin reinforced with glass fibres possesses excellent strength properties and even in the case of pipes laid in the ground, is just as resistant as the core and jacket pipes which are themselves, preferably, made from the same material, and has the necessary temperature stability.

One exemplified embodiment ofthe device in accordance with the invention is shown in the accompanying drawing, in which: Fig. 1 is a cross-sectional view of a preferred embodimentofthe device of the invention; Fig.2 is afragmentary part-sectional viewiltustrat- ing the device of Fig. 1 in position on a core pipe and about to be fitted to a jacket pipe, this figure being to a reduced scale compared with Fig. 1; and Fig. 3 is a view similar to Fig. 2 but showing the device in its sealing position on the pipes.

As illustrated in the drawing, a preferred embodiment ofthe device ofthe invention, which is for providing a seal forthe annular space between a core pipe 3 and an outer pipe or jacket pipe 6 comprises an annular disc 1 provided with a conical inner bore 2 which is adapted to the outside diameter of the core pipe 3. The annular disc 1 possesses two cylindrical portions 4 and 5 which are different in diameter and of which the cylindrical portion 4 is adapted to the inside diameter ofthe jacket pipe 6 and the cylindrical portion 5 is adapted to the outside diameter of the jacket pipe 6. The cylindrical portion 4 is subdivided by an annular groove 7.

As shown by Figs. 2 and 3, the core pipe 3 is seated concentrically in the jacket pipe 6 thereby forming an annular space which is filled with polyurethane hard foam 8.

Theannulardisc 1 is provided with a layerof adhesive over the region of the inner bore 2 as well as on the side facing the annular space which comes into abutment against the polyurethane foam when the annular disc 1 has reached the position provided for in Fig. 3. A sealing core 9 inserted previously into the annular groove 7 assists the sealing action between the annular disc 1 and the jacket pipe 6.

1. Adeviceforthefrontal closure of an annular space or chamber formed by a concentric arrangement of a core pipe or inner pipe inside a jacket pipe or outer pipe and filled with insulating material, characterised in that it comprises an annular disc having an inner bore adapted to the outside diameter of the core pipe and having different cylindrical portions which are adapted to the outside diameter and to the inside diameter respectively of the jacket pipe and of which the portion which is adapted to the inside diameter of the jacket pipe is subdivided by an annular groove.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A device for the frontal closure of an annular space This invention relatesto a device forthe frontal closureofanannularspaceorchamberformed bythe concentric arrangement ofa core pipe or inner pipe disposed inside a jacket pipe or outer pipe. To insulate a pipe through which a medium flows, it is known to arrange the pipe as core pipe concentri cally inside a jacket pipe and to fill, with insulating material, for example hard polyurethane foam, the annular space which is bounded by the outside of the core pipe and the inside of the jacket pipe. In orderto preventwaterfrom penetrating into the annular space, whereby the action of the insulating material would impaired or the insulating material would even be destroyed, for example where the pipes are laid in the ground, it is necessary to close off or seal the ends ofthe annular space which is filled with the insulating material.Forthis purpose it is known to usethermo plastic shrinkage sleeves which require a processing temperatureofoveri000C.On buildingsites,the effective incorporation of such shrinkage caps or sleeves is difficultand can be madeeven moredifficult byweather influences. Annular space sealings under taken in a place ofmanufacture do not, however, make further sealing work under building site conditions superfluous, since frequently standard pipe lengths sealed off in the place of manufacture have to be shortened on the building site on account of a change in direction or branch-off in the course of the pipeline. Added to this is the fact that the customarythermo- plastic shrinkage caps or sleeves soften at a core temperature over 60to 80 C and thus the sealing effect is considerably impaired. An object of the invention is to provide a device, for the frontal closure of an annular space between a core pipe and a jacket pipe, which can be easily installed even under building site conditions and which makes possible an absolutely water-tig ht and also tempera ture-stable closure. To achieve this object, in accordance with the invention an annular disc is proposed which is provided with an inner bore adapted to the outside diameter of the core pipe and with different cylindrical portions which are adapted to the outside diameter and to the inside diameter respectively of the jacket pipe and of which the portion adapted to the inside diameter ofthe jacket pipe is subdivided by an annular groove. Because of its design the annular disc in accordance with the invention can, in a simple manner, be slipped onto the core pipe and pressed against the jacket pipe and be bonded with the pipes so that an absolutely water-tightclosure ofthe annular space is brought about. In this respect, the sealing action is additionally improved by a sealing cord which is arranged in the annulargrooveoftheportionadaptedtothe inside diameter of the jacket pipe. In accordance with a development of the invention, the innerboreoftheannulardisc is conical in configuration and the maximum diameter of the inner bore lies on that side ofthe annular disc which faces the annular space. Asa result ofthis development, upon being pushed ontothecorepipe,theannulardiscactslikeascraper ring and causes there to arise inside the inner bore cone, from adhesive previously applied to the core pipe, a bead of adhesive which guarantees complete sealing between the core pipe and the annular disc. Finally, a development of the invention additionally provides for the annular disc to consist of duroplastic reaction resin reinforced with glass fibres. An annular disc produced from reaction resin reinforced with glass fibres possesses excellent strength properties and even in the case of pipes laid in the ground, is just as resistant as the core and jacket pipes which are themselves, preferably, made from the same material, and has the necessary temperature stability. One exemplified embodiment ofthe device in accordance with the invention is shown in the accompanying drawing, in which: Fig. 1 is a cross-sectional view of a preferred embodimentofthe device of the invention; Fig.2 is afragmentary part-sectional viewiltustrat- ing the device of Fig. 1 in position on a core pipe and about to be fitted to a jacket pipe, this figure being to a reduced scale compared with Fig. 1; and Fig. 3 is a view similar to Fig. 2 but showing the device in its sealing position on the pipes. As illustrated in the drawing, a preferred embodiment ofthe device ofthe invention, which is for providing a seal forthe annular space between a core pipe 3 and an outer pipe or jacket pipe 6 comprises an annular disc 1 provided with a conical inner bore 2 which is adapted to the outside diameter of the core pipe 3. The annular disc 1 possesses two cylindrical portions 4 and 5 which are different in diameter and of which the cylindrical portion 4 is adapted to the inside diameter ofthe jacket pipe 6 and the cylindrical portion 5 is adapted to the outside diameter of the jacket pipe 6. The cylindrical portion 4 is subdivided by an annular groove 7. As shown by Figs. 2 and 3, the core pipe 3 is seated concentrically in the jacket pipe 6 thereby forming an annular space which is filled with polyurethane hard foam 8. Theannulardisc 1 is provided with a layerof adhesive over the region of the inner bore 2 as well as on the side facing the annular space which comes into abutment against the polyurethane foam when the annular disc 1 has reached the position provided for in Fig. 3. A sealing core 9 inserted previously into the annular groove 7 assists the sealing action between the annular disc 1 and the jacket pipe 6. CLAIMS

2. A device as claimed in claim 1 characterised in thy; the inner bore ofthe annular disc is conical and the maximum diameter of the inner bore lies on that side of the annular disc which faces the annular space.

3. A device as claimed in claim 1 or 2, characterised in that the annular disc consists of duroplastic reaction resin reinforced with glass fibres.

4. A device for the frontal closure of an annular space or chamberformed by a concentric arrangement of a core pipe or inner pipe inside a jacket pipe or outer pipe substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.