Method for manufacturing a pipe flange joint.

The invention relates to a method for producing a tubular article, wherein a thermoplastic material in the form of a powder or granules with the addition of chemical crosslinking agents as well as additives and excipients is subjected to a high pressure in a pressure chamber, whereby the temperature of the mixture rises to about 110 ° C , after which the mixture is passed through channels of an extruder and heated to crosslinking temperature is still within the extrusion apparatus, the extruded hollow strand continuously drawn through a die in the same working process and cut the hollow strand thus obtained to length and at least one end for forming a flange member with formed head piece by means of a correspondingly shaped mold<ul><li>a. is partially heated above the crystallite melting, or</li><li>b. is pressed in the cold state (at room temperature) with high pressure,</li></ul> whereupon the heated or tabletted hollow strand end the desired shape change permanently occupying and for producing a flange of two thus formed hollow strand ends with integral flange, the molded headpiece each flange having an integral with the hollow strand outer collar whose outer diameter is larger than the outer diameter of the hollow strand, which in itself is extending the axial direction of the hollow strand on its end addition or set back by this amount.

For transporting flow media capable, for example, in heating or plumbing or in Automotion, are increasingly plastic products and in particular plastic pipes application. These materials have excellent long-term resistance also at high temperatures and pressures and are resistant to most in both plumbing and heating sector and in the automotive and other technical fields occurring accessories stably.

For example, if the pipes are subjected to during the installation of a strong bending, this can be done in a cold state, wherein the cross-sections narrow in the bends.

There are also known from DE-OF 31 52 022.7 methods are known which describe a one-sided heating, to achieve a deformation in which the bending zones have approximately the same cross section as the undeformed pipe.

Tubes of this type are preferably produced by the chemical crosslinking process according to DE-PS 16 79 826th

These pipes are characterized by a dimensional stability that persists even at temperatures above the crystalline melting point of about 140 ° C.

This can be very easily also multiaxial manufacture products, but still a considerable need simple, safe and tight Rohrbverbindungen there.

The present invention is based on the object, said method preferably applied to manufacture pipe connections in the form of flange connections.

This object is according to the invention that are produced by the known method hollow strands or tubes with molded head pieces and the assembled state of the flange abuts a respective metal ring against the perpendicular to the pipe casing extending surface of the outer collar and the metal rings of the flange using clamping elements are pressed together.

According to the invention, the pipe ends obtain a configuration which simplifies the production of a pipe flange, wherein the metal rings absorb the forces exerted by the clamping elements radial and axial force components and distributed approximately uniformly on the respective outer collar and act axially, so that the outer coils are pressed together. Here, the pipe material itself is used as a sealing material by structural shapes.

The outer rim of the molded head piece of hollow tubing or pipe end - viewed in cross section - is formed at right angles or has conical support surfaces, the metal rings abut flush with each corresponding shape.

In the invention, the metal rings have a cross-section of a tapered outer surface and the legs of the clamp formed as a clamping element are in this case provided with the same inclination.

In a further embodiment of the invention is in the assembled state of the flange connection between the Hohlstrang- or pipe ends a ring of metal, ceramic, metal-ceramic, plastic, or material the same plastic which an axis extending around the ring recess and / or a corresponding at its front sides having projecting collar, which are dimensioned so that the portion of the outer collar that extends beyond the end of the hollow strand or tube or is set back by this amount, the recess or the projecting collar of the ring corresponds.

This solution has the advantage that all the pipe ends may have the same shape, so that the manufacturing process of the end pieces much easier.

Another advantage of this solution is that the ring has at least one radial hole each having an inner thread for connection in each case one pipe fitting, so that pipe branches or distribution can be incorporated in a simple way and as required.

The abutting surfaces of the outer collar with the ring elements can in this case have a flat surface or a corrugated or meandering surface so that in a simple way, the sealing surfaces can be increased and seal chambers are formed, which greatly improve the sealing effect.

Further advantageous solutions are apparent from the remaining dependent claims.

The invention is further illustrated by the drawings, are illustrated in the various embodiments. In the figures:<ul><li>FIGURE 1 is a flange with metal rings and a clamp;</li><li>FIGURE 2 is a flange with conically shaped in cross-section metal rings and a clamp;</li><li>FIGURE 3 is a flange connection in cross section rectangular shaped metal rings, an intermediate ring and a clamp; </li><li>FIGURE 4 is a flange with conically shaped in cross-section metal rings, an intermediate ring and a clamp;</li><li>FIGURE 5 is a flange connection in cross section rectangular shaped metal rings with holes for jackbolts and an intermediate ring.</li><li>FIGURE 6 is a flange with conically shaped in cross-section metal rings with holes for jackbolts;</li><li>FIGURE 7 is a flange connection in cross section rectangular shaped metal rings with holes for jackbolts;</li><li>FIGURE 8 a and b has a metal ring with three holes for receiving clamping bolt;</li><li>Figure 9 a and b a metal ring with a conical inner surface and with three holes for receiving clamping bolt;</li><li>Figure 10 a and b show a clamp with a bolt tightening device, and</li><li>Figure 11 a and b show a clamp of a plurality of members.</li></ul>

1 shows a flange joint between two pipe ends 1 and 2 immediately prior to final assembly. Both headers of these pipe ends 1 and 2 are each provided with an integral outer collar 3 and 4 different shapes. In both cases the outside diameter are larger than the outer diameter of the pipe ends. The outer collar 4 is extending in the axial direction of the pipe 2 through the end of the tube 2 addition, while the molded headpiece of the other pipe end 1 is provided with an outer collar 3, which is set back in the axial direction of the pipe 1 to the part by which the outer collar 4 extends over the end of tube 2, so that these elements engage in one another after the final assembly.

Both outer coils 3 and 4 are rectangular in cross-section, so that their radial surfaces are directed perpendicular to the pipe casing. Against each radial surface of the outer coils 3 and 4, which are the respective tube faces 1 and 2, is a ring 5 or 6, which, if this punctiform or linear attack the forces of the clamp 7 on the metal rings 5 ​​and 6, be distributed over the entire circumference. The clamp 7 is considered in section U-shaped, with the legs 8 and 9 are inclined to the vertical. This can be in the final assembly a significant tightening effect in the axial direction can be achieved. The interlocking after final assembly outside Bunde 3 and 4 cause in addition to the abutting surfaces of the pipe ends 1 and 2, which can still be formed corrugated, a noticeable increase in the sealing surfaces, in particular through the meandering course of the surfaces.

2 shows a similar embodiment of Figure 1, but with the rings 5 ​​and 6 are replaced by Figure 1 through the rings 10 and 11, each having a tapered surface 12 and 13. FIG. The tendency of these annular surfaces 12 and 13 is approximately equal to the inclination of the U-shaped limbs 8 and 9 of the clamp 7, so that sufficient contact surfaces are present.

3 shows a flange in the preassembled state in which both end caps of the tube ends 14 and 14 'are provided each with an integral outer collar 4 and 4' having the same shape. In both cases the outside diameter are larger than the outer diameter of the pipe ends 14 and 14 '. The outer collars 4 and 4 'are in the axial direction of the tube over the end of the respective tube 14 or 14' also extends. In the pre-assembled and mounted state, is located between the Hohlstrang- or pipe ends 14 and 14 ', an intermediate ring 15 made of metal ceramics, metal-ceramic, plastic or material the same plastic which an axis extending around the entire intermediate ring recess 18 and 19 has at its front sides which are dimensioned such that the portion of the outer collar 4 and 4 ', which extends over the end of tube 14 or 14' extends, the respective recess corresponds, so that offset in the mounted state abutting surfaces are present which increase the effective sealing surfaces noticeably , The metal rings used 5 and 6 correspond to the metal rings according to FIG. 1

The ring 15 is also provided with a hole 16 having the pipe joint 17th For the implementation of the pipe connection 17, the clamp 20 is also equipped with a bore 21st In an unillustrated embodiment of the invention the ring 15 is equipped with several pipe connections 17, which may also have different tube cross sections. Since the ring 15 can be easily replaced, a suitable cross-linking of a pipe system can be done in a simple manner.

4 shows an embodiment which corresponds to that of Figure 3, but with the deviation that the metal rings 5 ​​and 6 are provided according to FIG 3 in Qerschnitt each having a tapered outer surface 22 and 23, wherein the inclination of the inclination of the U- -shaped legs 24 and 25 of the clamp 20 corresponds. The remaining elements are alike and are therefore provided with the same reference numerals.

5 shows a flange connection with an intermediate ring 26 which is formed at its periphery on both end sides with a peripherally closed bead or spring 27 and 28th Correspondingly, the pipe ends 34 and 35 each have a groove 29 and 30 for receiving the respective bead 27 and 28 are provided in the outer collar in each end. As a tensioning element metal rings 31 and 32 are provided, which are clamped by bolts 33rd The metal rings are described with reference to FIG. 8

6 shows a flange joint of the pipe ends 36 and 37 with a clamping element of metal rings 38 and 39, which are clamped with a clamping bolt 33rd The metal rings 38 and 39, which are described in more detail with reference to FIG 9, each comprise a conical inner surface 40 and 41 which abut respectively against a correspondingly formed conical surface of the outer collar.

7 shows a further embodiment of the invention. Here, the end faces of the outer coils 42 and 43 are provided with a groove 44 and a corresponding bulge or spring 45th When clamping element metal rings 31 and 32 are used according to Figure 5, which are clamped by bolts 33rd

8 shows in plan view a) and in cross-section b) a metal ring 31, which is provided with three holes 46, 47 and 48 to carry out bolt 33 in order to tension with a similar counterpart. When assembled, the flange each have a metal ring 31 abuts against the tube to coat extending surface of the outer collar and the bolt takes place mutual distortion and thus the final assembly of the flange.

9 shows in Draufsich a) and in cross section b) a metal ring 38, similar to Figure 8 shown, but with a conical inner surface 40 (s. Also FIG 6).

10 shows a clamp constructed as a 7 tensioning device in plan view a) with bolts and clamping element 52 in accordance with b), which is rotated by 90 °. The clamp 7 comprises two parts 49 and 50 which are pivotable about the axis 51st The clamping element 52 has a pin guide member 53, which is pivotally mounted about the axis 54th The pin guide member 53 is provided with a bore, while the corresponding counterpart in the part 49 of the clamp is provided with an internally threaded bore, so that the bolt screwed 33 and the clamp can be clamped 7 for carrying out the bolt 33rd

11 shows a formed as a multi-element clamp 55 clamping device in a plan view) with bolt 33 and clamping element 52 in accordance with b), which is rotated by 90 °. The clamp 55 consists of four parts 56, 57, 58 and 59, which are formed around the axles 60, 61 and 62 pivotable. The tensioning element 52 has, as in the embodiment of Figure 10, a pin guide member 53 on which is pivotally mounted about the axis 54th The pin guide member 53 is provided with a bore, while the corresponding counterpart in the part 56 of the clamp 55 is provided with an internally threaded bore, so that the bolt screwed 33 and the clamp 7 can be tensioned for carrying out the bolt 33rd

The clamping element according to figure 11 has the special properties that the clamping forces cause clamping of a circular tube, which are deflected via the metal rings in the axial direction of the tubes, so that an oval deformation of the pipe ends is excluded.

The invention enables the production of flanged connections of unerschiedlichsten types, the use of an intermediate ring with pipe connections in an advantageous manner, enables a plurality of taps.