DE3533000A1 - Socket pipe joint for plastic pipes - Google Patents

Abstract

The socket pipe joint for plastic pipes, in particular for helical-tape-wound pipes of PE, PP or the like, with and without rib-like pipe wall reinforcement, consists of a socket, a spigot end and an elastomeric sealing ring premounted thereon. In addition, at the axially outer start of the socket pipe joint part (socket or spigot end) bearing the premounted sealing ring, a centring ring is arranged which projects radially beyond the socket inner wall or beyond the spigot end outer wall. The centring ring consists of the same or a similar plastic material to the socket pipe joint part bearing the premounted sealing ring. The socket pipe joint part, together with the centring ring, forms a functional unit which, due to thermoplastic shaping, has a thickened edge or, due to a thermally or chemically effected melt bonding of the socket pipe joint part and the centring ring, has a materially homogeneous firm consistency.

Description

The invention relates to a socket pipe connection for plastic pipes, especially for spiral wound tubes made of polyethylene, polypropylene or the like with and without rib-like pipe wall reinforcement, consisting of sleeve, Pointed end and one pre-assembled on the socket or on the pointed end Sealing ring made of elatomeric material, at the axially outer beginning of the, bearing the pre-assembled sealing ring Sleeve pipe connecting part (sleeve or spigot end) a centering ring is arranged over the inner wall of the sleeve or radially beyond and beyond the tip end outer wall the assembly of the plastic pipe in the socket gap Socket pipe connection protrudes radially, this centering ring the axial termination on each side of the socket gap forms.

For the construction of sewage and rainwater sewers or the like preferably spiral-wound plastic pipes with and without profiled tube wall reinforcement and with smooth pipe inner surface according to DIN 16 691 for years practical use. The standard pipe sizes of these Plastic pipes range from DN 300-DN 3000. The connection from tube to tube is usually done using factory-wrapped sleeve and a pointed end, which inserted into the sleeve when installing the plastic pipe becomes. Then the socket pipe connection thus created sealed by extrusion welding. As simple as this sealing process seems, so It is difficult to do the necessary work on the Construction site in the narrow pipe trench with the necessary care also execute. Especially with the nominal pipe sizes DN 300  up to DN 800, the weld must be inaccessible Plastic pipes are made from the outside, what on the, on the Trench bottom of the bottom of the pipes is not easy is to be accomplished. There is also the problem that the plastic pipes during longer storage, esp. when stacking several pipes on top of each other, in Cross-section not insignificant and often also uneven deform. This already results in Put the socket and spigot end together in the pipe trench additional difficulties. Reaching an all around tight pipe connection therefore also depends on these pipes largely depends on the care with which the installation staff carries out this work, and which is known at the bad weather conditions that often prevail at the construction sites and the tight conditions in the pipe trench is not always given.

It is an object of the invention to provide a socket pipe connection for plastic pipes of small and large nominal sizes, in which the disadvantages of the known socket pipe connections be avoided.

This object is achieved in that the Centering ring made of the same or a similar one Plastic material like the pre-assembled sealing ring load-bearing sleeve pipe connection part - sleeve or spigot end - exists, and that this socket pipe connection part together forms a functional unit with the centering ring by thermoplastic molding of an edge thickening or through a thermally or chemically caused fusion of socket pipe connection part and centering ring one homogeneous solid consistency. Homogeneous materials means in this case that the centering ring under the expected loads, e.g. B. in eventual Deformations of the cross section of the plastic pipes during transport and storage as well as all occurring Weather conditions, similar to that preassembled sealing ring-bearing connecting tube connection part  behaves that he z. B. does not break, does not become brittle, not completely or partially from the socket pipe connection part replaces or the like. But that he at least one just as good durability and functionality as that Has plastic pipe or its socket pipe connecting part. Through the permanent fixed achieved in this way Connection between the centering ring and the adjacent socket pipe connection part is reliably guaranteed that the centering ring even when the pipes and tubes are stored for a long time in the event of any deformation of its cross section original position at the socket or at the tip end of the Retains plastic tube. This opens up the possibility also plastic pipes made in this way using sealing rings made of elastomeric material to seal securely. The centering ring takes over the necessary precise pre-centering for the one that enters the sleeve when the pipe is installed Pointed end, so that the sealing ring also during assembly of plastic tubes slightly deformed in cross section largely uniformly pressed over its entire circumference is, an undesirable axial displacement of the Sealing rings in or out of the socket gap are no longer possible is. As the sealing ring for individual versions the invention pre-assembled at the factory and with the it supporting sleeve pipe connection part are firmly connected can be carried out at the construction site Sealing work to a minimum - applying the Lubricant on the sealing ring - reduce and thus that Leakage occurs when the pipe connection is made exclude practically completely.

According to a further development of the invention, the rational production of the socket pipe connection according to the invention provided that the centering ring from a radial on the socket pipe connection part of the plastic pipe or applied second plastic winding layer.

In another embodiment of the invention, something during transport or when storing in cross section  deformed plastic pipes the necessary centric Approaching the tip end on or in the sleeve during assembly the pipes are thereby facilitated or ensured that the centering ring on its axially outer End a conical centering surface or a has clear centering.

The one required or desired in some applications Transport and largely disassembly-safe factory Attaching the sealing ring to the sleeve or on Pointed end of the plastic tube can be with another advantageous embodiment of the invention in a simple manner accomplish by the radial edge reinforcement of a connecting web extending in the axial direction from the sealing ring in a, between centering ring and radially adjacent Socket pipe connecting part located recess is arranged.

This applies to certain types of socket pipe connections necessary support of sealing rings against axial Moving during assembly is another Advancement of the invention thereby advantageously certainly ensures that - from the axially outer beginning of the preassembled sealing ring connecting tube connecting part seen here - one axially behind the sealing ring gradation protruding radially into the socket gap area.

Especially in the case of plastic pipes with a large nominal diameter, another embodiment of the invention for work acceleration and thus contribute significantly to reducing costs, that between the, the pre-assembled sealing ring bearing sleeve pipe connecting part and the centering ring existing material-homogeneous solid consistency only on one or several sections of the circumference of the centering ring is available.

The invention is based on the drawing and the contained therein Embodiments explained in more detail. It show in  Sectional pipe axial longitudinal section:

Fig. 1, the axially outer ends of a conventional socket pipe connection of a plastic pipe shortly before assembly;

5, three manufactured according to different manufacturing processes sleeves Figure 2, Figures 3 and with pre-mounted sealing rings...;

. Figure 4 illustrates the factory attaching a centering ring on the sleeve of a plastic tube;

Fig. 6 is a mounted on the spigot end of a plastic tube centering ring with pre-sealing ring;

Fig. 7 is a centering ring attached to the sleeve of a plastic pipe with a factory-fitted sealing ring.

In Fig. 1, the sleeve 1 and the tip end 2 of a plastic tube have the conventional axial cylindrical shape. The connection points 3 formed during the manufacture of the sleeve 1 , which result from mutual fusion of previously extruded plastic strips wound in parallel on a cylindrical mandrel, are indicated by dashed lines. As a result of deformations in the cross-section of the plastic pipes, which often arise during their transport or during long storage, the sleeve gap width 4 between the two sleeve pipe connection parts sleeve 1 and spigot end 2 can differ significantly over the entire circumference of a single sleeve pipe connection, which affects the assembly of the plastic pipes, above all with large nominal sizes, may be a difficult and labor-intensive problem.

According to FIG. 2, the sleeve 1 , which is initially produced as in FIG. 1, has a different radial wall thickness which is produced by thermoplastic molding. This formation takes place, for. B. in such a way that a portion of the axially outer end of the initially axially cylindrical sleeve 1 after the other by thermal treatment (hot air, heat radiation or the like.) Continuously brought back into a plastic state and then by a, the plasticizing device downstream pressure roller system or the like. Is formed to the desired new wall cross section. Here, for. B. the plastic tube moves around its own axis, which allows a largely automatic deformation of the sleeve 1 . After completion of this manufacturing process, the sleeve 1 has at its axially outer end the centering ring 5 with a conical centering surface 6 in the form of a radially inward thickened edge. The centering surface 6 considerably facilitates the exact pre-centering of the tip end 2 and its subsequent assembly, even in the case of plastic pipes which are severely deformed in cross section. Axially behind the centering ring 5 there is a radial extension of the sleeve 1 as a receptacle 7 for the preassembled sealing ring 8 , which is supported axially against shear by a retaining lug 9 projecting over its cross section against the radially inward gradation 10 of the sleeve 1 . In the embodiment variant shown here, the gradation 10 has only a small radial height which, when the pointed end 2 of the plastic pipe to be laid can be fitted, can be easily overrun by the sealing ring 8 designed as a rolling ring. The gradation 10 in connection with the retaining lug 9 of the sealing ring 8 has the task of preventing an undesirable axial displacement of the sealing ring 8 at the beginning of the assembly and of ensuring that the sealing ring 8 rolls evenly into the sleeve gap during the assembly.

According to FIG. 3, the centering ring 5 is fastened to the end wall of the sleeve 1 in a material-homogeneous manner by means of a thermally or chemically effected fusion connection (dashed lines). The chemical melting of the two connecting surfaces on sleeve 1 and centering ring 5 takes place with suitable types of plastic, such as. B. in PVC, by painting a suitable solvent or a solvent adhesive and then pressing together the parts to be connected. The radial height of the step 10 corresponds to the radially projecting inwardly over the seat 7 of the sealing ring 8 width of the centering ring 5 and approximately the radius of the sealing ring. 8 Due to this extent of the radial height of the gradation 10 , it can no longer be rolled over by the sealing ring 8 when the plastic tube is being installed. In this case, the sealing ring 8 is suitable for use as a sliding ring which is coated with a lubricant shortly before assembly and is then pressed radially together by the spigot end 2 entering the sleeve 1 .

Fig. 4 shows the production of a thermally induced fusion bonding between the end wall of the sleeve 1 and the adjacent contact surface of, made of the same plastic material as the sleeve 1 centering ring. 5 Both surfaces - the end wall of the sleeve 1 and the contact surface of the centering ring 5 - are first plasticized by hot air, heat radiation or the like (shown in broken lines). Then both surfaces are pressed tightly together, so that after they cool, a fusion of homogeneous solid consistency is formed. The centering ring 5 has a - in axial part 11, which ensures a correct mounting position of the centering ring 5 and the socket 1 - axially of the sleeve mirror extending.

In FIG. 5, the play function unit of a socket pipe connection, consisting, shown from the box 1 and in the terms of its texture and shape already from Fig. 4 ago known centering ring 5. Between the end face of the sleeve 1 and the adjacent previous contact surface of the centering ring 5 there is the melt connection of homogeneous material consistency which is already explained in FIG. 4 and shown here in broken lines, and which can safely withstand all loads occurring during transport and storage of the pipes. The axial pre-assembled behind the centering ring 5 sealing ring 8 is formed as a sliding ring.

Between the pointed end 2 shown in FIG. 6 and the centering ring 5 attached to its radial outer wall 12 and between the axially further spaced gradation 10 there is in each case a thermally or chemically effected fusion connection (dashed) of material-homogeneous solid consistency. The centering ring 5 and the gradation 10 protruding radially outward beyond the outer wall 12 of the spigot end 2 are expediently likewise carried out by the winding method by melting a respective second winding layer with a corresponding cross-section onto the outer wall 12 . The pre-assembled sealing ring 8 between the centering ring 5 and the radially protruding step 10 has an approximately triangular basic cross-section as a sliding ring, which is compressed radially when the pointed end 2 is inserted into the sleeve 1 . The gradation 10 here serves for the sealing ring 8 as an axial thrust safety device which supports it axially. The centering ring 5 has at its axially and radially outer end a clear centering curve 13 , which has the same functional task as the centering surface 6 shown in FIG. 2 during assembly.

In FIG. 7, the radial edge reinforcement 14 of a connecting web 15 extending from the sealing ring 8 in the axial direction lies in a recess 16 located on the axial part 11 of the centering ring 5 . Both parts - centering ring 5 and sealing ring 8 - are already preassembled in their sleeves 1 in the manufacturer of the plastic pipes. A transport safe and - in either direction - axialschubsichere connection between the pre-mounted sealing ring 8 and the sleeve 1 to achieve, is extruded onto a plurality of portions of the circumference of the centering ring 5, a relatively thin plastic band 17 to the end wall of the sleeve 1, and thereby, with the on a radial portion of this end wall of the radial part 18 of the centering ring 5 thermally fused (shown in dashed lines). At the construction site only the sealing ring 8 needs to be coated with the lubricant and the plastic pipes have to be installed, and the socket pipe connection is tight. Due to the material-homogeneous solid consistency of the functional unit consisting of the socket pipe connection part - in Fig. 7 from the socket 1 - and the centering ring 5 , socket pipe seals for such plastic pipes can now be prefabricated at the factory and easily assembled on site by simply plugging the socket 1 and spigot end 2 together whose cross-section may deform significantly during transport and storage - usually to a kind of egg profile.

• Reference number list 1 sleeve
  2 spiked ends (SPE)
  3 connection points
  4 socket gap width
  5 centering ring (ZR)
  6 centering surface of the ZR
  7 recording (for DR)
  8 sealing ring (DR)
  9 retaining nose
  10 gradation
  11 axial part (of the ZR)
  12 radial outer wall (of the SPE)
  13 centering (of the ZR)
  14 radial edge reinforcement (of the DR)
  15 connecting bridge (of the DR)
  16 recess (of the ZR)
  17 plastic strap
  18 radial part (of the ZR)

Claims (6)

1.Socket pipe connection for plastic pipes, especially for spiral-wound pipes made of polyethylene, polypropylene or the like with and without rib-like pipe wall reinforcement, consisting of a sleeve, spigot end and a pre-assembled on the sleeve or spigot end sealing ring made of elastomeric material, at the axially outer beginning of the pre-assembled sealing ring bearing sleeve pipe connecting part (sleeve or spigot end) a centering ring is arranged, which projects radially beyond the inner sleeve wall or over the outer tip end wall and radially protrudes into the sleeve gap of the sleeve pipe connection after assembly of the plastic pipe, this centering ring in each case having the axial closure on one side of the socket gap, characterized in that the centering ring ( 5 ) consists of the same or a similar plastic material as the socket pipe connection part carrying the pre-assembled sealing ring ( 8 ) - socket ( 1 ) or spigot end ( 2 ) - and that Socket pipe connection part ( 1 or 2 ) together with the centering ring ( 5 ) forms a functional unit which has a material-homogeneous solid consistency through thermoplastic molding of an edge thickening or through a thermally or chemically caused fusion connection of the socket pipe connection part ( 1 or 2 ) and centering ring ( 5 ). 2. Socket pipe connection according to claim 1, characterized in that the centering ring ( 5 ) consists of a radially on the socket pipe connection part ( 1 or 2 ) of the plastic pipe or applied second plastic winding layer. 3. Socket pipe connection according to claims 1 and 2, characterized in that the centering ring ( 5 ) has at its axially outer end a conical centering surface ( 6 ) or a clear centering rounding ( 13 ). 4. sleeve pipe connection according to claims 1 to 3, characterized in that the radial edge reinforcement ( 14 ) of the sealing ring ( 8 ) in the axial direction connecting web ( 15 ) in a, between centering ring ( 5 ) and radially adjacent sleeve pipe connecting part ( 1 or 2 ) located recess ( 16 ) is arranged. 5. sleeve pipe connection according to claims 1 to 4, characterized in that - seen from the axially outer beginning of the preassembled sealing ring ( 8 ) bearing sleeve pipe connection part ( 1 or 2 ) - an axially behind the sealing ring ( 8 ) projecting radially into the sleeve gap area Gradation ( 10 ) is located. 6. sleeve pipe connection according to claims 1 to 5, characterized in that between the, the preassembled sealing ring ( 8 ) bearing sleeve pipe connection part ( 1 or 2 ) and the centering ring ( 5 ) existing material-homogeneous solid consistency only on one or more partial areas of the circumference the centering ring ( 5 ) is present.