DE7736415U1 - EXPANSION PART WITH AN ELASTIC PLASTIC BELLOW TO CONNECT TWO PLASTIC PIPES - Google Patents

Description

Patent attorney Dr. jur. J _t QA £! HI ^ gANjDIVlANN ₁ Dipl.-Ing. 8O14 Neubiberg, Rathausplatz 18, phone CO89 ^) 6O38OO

itl. File number: New registration My reference: I792

reporter): _{Dr> Erns} t Schnabel, Limburg / Lahn

Description concerning

Expansion part with an elastic plastic bellows for Connecting two plastic pipes.

The invention relates to an expansion part with an elastic Plastic bellows for connecting two plastic pipes.

It is known to use plastic bellows such as polytetrafluoroethylene to be arranged between the facing ends of two plastic pipes in order to connect the two pipes together. The bellows can change the distance between the pipe ends caused by thermal expansion or contraction can be caused, as well as axial misalignment and compensate for an angular position deviating from the coaxial arrangement between the plastic pipes to be connected. Included the bellows carries outwardly protruding flanges at both ends, which are connected to the corresponding connecting flanges connecting pipes are clamped in a sealing manner, for which purpose metal ring washers are used, which are attached to the back of the plastic the flanges are in contact, radially beyond the plastic flanges protrude and are clamped together at their peripheral area by screw bolts.

Although this known training ensures the desired elastic Compensation with simultaneous tight connection of the

two plastic pipes, but requires the Ends of the plastic pipes and the plastic bellows, whereby Weak points arise. Furthermore, each of the two flange connections requires at least three circumferentially distributed Screw connections, which leads to a corresponding effort when installing or later removing the plastic bellows. Finally, the not only insignificantly radially projecting flanges beyond the pipe circumference can also be used, depending on the spatial Disturb circumstances.

According to the invention, these disadvantages are to be eliminated, without compromising the function of the expansion part. The task is accordingly To see the invention in the creation of an expansion part of low manufacturing costs, which is reduced with Can be installed and removed effort, leads to a compact space-saving connection and an increased guarantee for offers absolute tightness even after a long period of operation.

This object is achieved in that the Plastic bellows has two tubular ends, each wear a union nut and a conically widened one Have end portion that rests against a correspondingly conical inner circumferential surface of the union nut, and through two connectors, each having a socket section for fixed connection with one plastic pipe end, one with the Union nut screwable tubular threaded section and a clamping section axially protruding from the threaded section have that with a konischai outer peripheral surface to rest on the inner circumference of the expanded end portion of the Plastic bellows is provided.

In this training, the two are to be connected to each other Plastic pipe ends each in the socket section of a of the two connectors welded or glued in, whereby

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a permanent connection between these parts is created, especially since the connectors are made of one of the material of the Plastic pipes can be made of adapted material, to ensure a good weld. Despite the firm connection of the two connecting pieces, the plastic bellows install and remove due to its elongation. For this purpose, only the two can be screwed to one of the connecting pieces Tighten or loosen union nuts. When screwing the union nut with the associated connection piece the relevant expanded bellows end between the conical inner circumferential surface of the union nut and the conical Outer circumferential surface of the clamping section on the connection piece clamped in a sealing manner, advantageously inevitably clamped uniformly over the entire circumference is achieved. It has been shown that even with a slight conicity of the clamping surfaces, a perfect seal is achieved, so that the bellows ends only have to be expanded to a correspondingly small extent, with Weaknesses due to local wall thickness reductions or the formation of rips are not to be feared. It can also be seen that the connecting pieces or union nuts do not have significantly larger radial dimensions than those to be connected Must have plastic pipes or the plastic bellows.

Another advantage results from the fact that the expansion part simply by exchanging the connection pieces for those with a different socket section plastic pipes different diameter can be adjusted. However, if possible, a plastic bellows is preferably used whose unexpanded tubular ends have an inner diameter which is the inner diameter of the plastic pipes to be connected corresponds, wherein the connecting pieces have a corresponding through hole to a possible

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to achieve smooth flow.

Appropriate refinements and developments result from the subclaims.

An exemplary embodiment of the invention is given below a schematic drawing explained in more detail, which in a longitudinal section, the two through the subdivided bellows with each other connected ends of the expansion part shows.

The expansion part comprises a bellows 1 made of polytetrafluoroethylene, which has tubular ends 2 and 3, which merge into a slightly conically widened end section h and 5, respectively. The ends of the bellows 2 and 3 each carry a union nut 6 or 7 made of aluminum, which is provided with a correspondingly conical inner circumferential surface 8 or 9. As indicated in the drawing, the inner circumferential surfaces 8 and 9 are grooved in the area of contact with the widened bellows section h and 5, respectively, whereby tooth-shaped elevations and depressions are formed which ensure particularly good mechanical contact with the end sections h and 5.

A connection piece 12 or made of polypropylene is assigned to each end of the bellows 1. The two connectors are designed identically and consist of a socket section 14 and 151, respectively, a threaded section i6 and 17, respectively, and a clamping section 18 and 19, which are arranged axially one behind the other in the order mentioned and have a through-hole 22 and 23, respectively. In the installation position shown the external thread of the threaded sections 16 and 17 is screwed to the internal thread of the union nuts 6 and 7, respectively. There is a provided on the clamping sections 18 and I9, likewise conical and grooved outer circumferential surface 20 or 21 from the inside on the expanded bellows section

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4 or 5 ^to » ^so that this is clamped firmly and sealed between the surfaces 8 and 20 or 9 and 21.

As shown, the outer circumferential surfaces 20 and 21 of the clamping sections 18 and 19 extend beyond the grooved contact area to the threaded section 16 and 17, so that a small cavity remains within the union nuts 6 and 7 in front of the end face of the widened bellows sections k and 5. This cavity can accommodate an O-ring 2k or 25.

The drawing also shows the ends 28 and 29 of the ends 28 and 29 to be connected to one another which are welded into the socket sections 1 k and 15. Plastic pipes can be seen.

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Claims (1)

Patent attorney Dr, Jur. JOACHIM SiANDMANN ₁ Dlpl.-Ing. Off · a a J · ■ · ι ■ j O I f 1 1 t 8O14 Neublberg, Rathausplatz 18, phone 0089) 60 38 00 Official, file number: New registration My reference: 1792 Applicant: Dr. Ernst Schnabel, Limburg / Lahn Expectations 1. Expansion part with an elastic plastic bellows for connecting two plastic pipes, characterized in that the plastic bellows (i) has two tubular ends (2,3), each of which carries a union nut (6,7) and a conically widened end section (4, 5), which rests on a correspondingly conical inner circumferential surface (8,9) of the union nut (6,7), and by two connecting pieces (12,13), each of which has a socket section (14, I5) for a fixed connection to a plastic pipe end ( 28, 29), a tubular threaded section (16, 17) that can be screwed to the union nut (6, 7) and a clamping section (18, 19) which projects axially from the threaded section and which has a conical outer circumferential surface (20, 21) for contact with the inner circumference of the expanded end portion (k, 5) of the plastic bellows (1) is provided. 2. Expansion part according to claim 1, characterized in that the conical inner peripheral surface (8.9) the union nuts (6,7) and the conical outer peripheral surface (20, 21) are grooved on the clamping section (18,19) of the connecting pieces (12,13). 3. Expansion part according to claim 1 or 2, characterized in that each union nut (6,7) receives an O-ring (2 ⁱ t, 25), which with its Innenurafang on one of the threaded portion (16,17) adjacent surface of the protruding Einspannäbschnitts (18,19) is applied. 7736415 02.03.78 Ill » 1 II * ♦ * Expansion part according to one of claims 1 to 3> characterized in that the connecting pieces (12, 13) consist of a plastic, in particular polypropylene. 5. Expansion part according to one of claims 1 to h, characterized in that the plastic bellows is a T bellows (i) made of polytetrafluoroethylene. 6. expansion part according to one of claims 1 to 5, characterized in that the union nuts (6,7) made of metal, especially light metal. 7736415 03/02/78