WO2008053050A2

WO2008053050A2 - Fitting for a pipe

Info

Publication number: WO2008053050A2
Application number: PCT/EP2007/061885
Authority: WO
Inventors: Bernd Kaufmann
Original assignee: Uponor Innovation Ab
Priority date: 2006-11-03
Filing date: 2007-11-05
Publication date: 2008-05-08
Also published as: DE102006051774A1; WO2008053050A3

Abstract

The fitting for a pipe, in particular for a pipe having a plastic layer on its inside, is provided with a fitting body (15), which comprises plastic material and is provided with at least one coupling region (36) for the pipe, and a metal insert element (16) which has at least one tubular passage section (18) and is enclosed at least partially by the plastic material of the fitting body (15). The tubular passage section (18) has on its inside (22) a plastic material layer (28) which is guided around at least one axial end (26) of the tubular passage section (18) and extends into the outside region (24), adjacent to the end (26), of the tubular passage section (18). The at least one coupling region (36) is formed by the plastic material layer (32) on the outside region (24) of the tubular passage section (18).

Description

Fitting for a pipe

The invention relates to a fitting for a pipe, which is in particular a pipe having a plastic layer on its inside.

Fittings for the connection of pipes whose walls consist entirely of plastic material or of a metal-plastic composite material are known in many embodiments. The fitting body of the known fittings usually consist of either plastic or metal. Metal is preferred for its strength, while a plastic fitting is prone to corrosion because of its corrosion resistance

In addition, there are proposals in the art for fittings that have metal elements that are partially covered by plastic material of the fitting body. Examples of this type of fitting can be found in DE 26 26 302 Al, DE 199 57 601 Al and DE 84 06 562 Ul. With these known materials, it is possible for the medium (for example water) inside the fittings to come into contact with metal, which contradicts the fundamental idea of the use of a plastic installation system and entails, among other things, the danger of corrosion. In addition, the permanent sealing of the interface between metal and plastic is problematic- Due to the different thermal behavior of the two materials produced in the plastic considerable mechanical stresses that must be compensated by some very large wall thicknesses or additional sealing elements.

The object of the invention is to provide a fitting for a pipe, the plastic material and metal, however, has no interface between the two materials and therefore has improved corrosion protection. To solve this problem, the invention proposes a fitting for a pipe, in particular a pipe having a plastic layer on its inner side, the fitting being provided with

- A fitting body, which has plastic material and is provided with at least one connection region for the tube, and at least one tubular passage portion having metal insert element which is at least partially enclosed by the plastic material of the fitting body, - wherein the tubular passage portion has on its inside a plastic material Läge which is guided around at least one axial end of the tubular passage section and extends into the outer side region of the tubular passage section adjacent to the axial end, and wherein the at least one connection region of the fitting body is formed by the material material on the outer side region of the tubular passage section.

Analogously, the fitting according to the invention comprises a metal insert element with a tubular passage section, which is also coated on the inside and at least one axial end of plastic material outside the Kunststoffrnaterialbereich forms the at least one connection region of the fitting, within which a pipe to be connected are brought into close contact with the fitting body can. This is done for example by a press or a sliding sleeve or by a screw connection (for example: slotted ring with union nut). Here, according to the invention, all known pipe connection techniques are conceivable.

By the lining of the metal insert element or of its at least one tubular Durchiassabεchnitt is ensured that the flowable

Medium that passes through the fitting does not come into contact with the metal insert element of the fitting. This is in the connection area of the fitting body thereby ensuring that in this connection region of the fitting body has a Kunststoffmateriailage.

Pipe fittings may have different constructive designs for a wide variety of purposes. Serves the Fftting as a pure pipe connector, it has at least two connection areas (preferably at the axial ends of its tubular passage section). Also conceivable are T-shaped fittings to which three tubes can be connected. According to the invention, all of these fittings have correspondingly designed metal insert elements with a number of tubular passage sections corresponding to the intended use, which according to the invention are lined on the inside with the plastic material of the fitting body and also have plastic material within each of their connection areas. In that regard, therefore, the metal insert element is embedded in the plastic material of the fitting body. The production of such a fitting according to the invention is effected by injection molding, wherein the respective metal insert element has been previously inserted into the injection mold.

To improve the frictional connection between the metal insert and the plastic material of the fitting body, it is expedient if the metal insert element is structured on its surfaces provided with plastic material. This can be done for example by a longitudinal or peripheral toothing, by knurling or other projections. A helical toothing (preferably with intersecting circumferential ribs) is conceivable. As a result, the composite material of metal and plastic is given an additional positive connection. Such a positive connection can additionally or alternatively also be realized in that the metal insert element has perforations, via which the inside of the metal insert element are connected to those outer side regions of the metal insert element within which, as on the inside, plastic material is present. In many cases pipe fittings are connected to other media-carrying units, such as pipelines, water supply equipment or the like. These fittings have connection ends that connect them to the media-tight units. According to the invention, the fitting body, if it has such connection ends, is likewise provided with plastic within these connection ends, which covers the meta-insert element which extends into this connection end region. If an internal or external thread is formed at the connection end, then this is according to the invention in the Kunststoffmateria! incorporated, which applies equally to the formation of the thread on the inside or on the outside of the connection end of the fitting body.

In order to be able to connect a pipe fitting to a (other) liquid-medium-carrying unit, it is expedient if tool attachment sections or at least one tool attachment section are / is formed on the fitting body. According to the invention this can be realized in an advantageous embodiment in that the Fittiπgkörper is within its Werkzeugansetzabschnitts of Kunststoffmateriai or metal.

The invention will be described below with reference to several embodiments and with reference to the drawings. In detail, they show:

1 shows a longitudinal half section through a first embodiment of a fitting with a metal insert embedded in plastic,

2 shows a longitudinal half section through a second embodiment of a fitting with a metal insert element embedded in plastic,

Fig. 3 is a longitudinal half section through a third Ausführungsbeispie! a fitting with a metal insert embedded in plastic, and 4 shows a longitudinal half section through a fourth exemplary embodiment of a fitting with a metal insert element embedded in plastic.

1 shows a first exemplary embodiment of a fitting 10 to which a tube 12 is tightly connected by means of a compression sleeve 14 in this embodiment for the medium flowing through the tube 12. The fitting 10 comprises a fitting body 15 which has a metal insert element 16 with a substantially tubular passage section 18. The tubular passage section 18 is formed by a cylindrical wall 20 of the metal insert element 16, which has an inner side 22, an outer side 24 and an axial end 26.

On the inside 22, the wall 20 of the tubular passage portion 18 with a plastic layer 28 is coated. This plastic läge 28 extends into a region 30 around the end 26 of the wall 20 and from there to beyond the outside 24 of the wall 20. The located in this area plastic material layer 32 may be profiled on its outer side 34 and forms the pipe connection area As shown in FIG. 1, at least one receiving groove 38 for a sealing ring 40 may be located in the section 34 of the plastic layer.

In the illustrated embodiment, the outermost plastic material layer 32 does not extend over the entire outside 24 of the wall 20. This portion of the plastic material layer may cover the entire outside 24 and should extend at least within the connection region 36.

1, the fitting 10 also has plastic on the inner side 22 and the outer side 24 of the wall 20 of the metal insert element 16 at the end 42 of its fitting body opposite the contact region 36. In addition, at the end 42 on the inner side 44 of this Kunststoffrnanteiung a screw thread 46 ausgebil- det. On the outer side 48 of the plastic casing at the connection end 42 of the fitting 10 there is a circumferentially extending, circumferential radial projection 50 which, for example, has a hexagonal profiling and serves as a tool attachment portion 52 of the fitting 10. In this embodiment, therefore, the Werkzeugansetzabschnϊtt 52 is formed entirely of plastic. For example, an open-end wrench or a pair of pliers can be attached to the radial projection 50, with which the fitting 10 can be screwed at its connecting end 42 onto a water-conducting unit (not shown) (for example, pipe socket or appliance nozzle).

1, the wall 20 of the metal insert element 16 has a multiplicity of holes or through-holes or similar perforations or recesses 54 which connect the outside 24 to the inside 22 of the wall 20 of the metal insert element 16. In the manufacturing process of the fitting 10, in which the Metallleinsatie-ie- element 16 is molded with Kunststoffmateriai, plastic material also enters the recesses 54, thereby resulting in an improved mechanical connection between the plastic and the metal of the metal insert element 16. This positive connection can also be achieved by a Profiiierung the Metalieinsatzelements 16 on the inner and outer sides 22,24 of the wall 20.

FIGS. 2 to 4 show alternative embodiments of fittings 10 ', 10 "and 10'", all of which are characterized by metal insert elements at least partially embedded in plastic, wherein, as also shown in FIG To conductive medium in contact surfaces of the fitting are covered with plastic. Same elements of the respective fittings according to FIGS. 1 to 4 are provided with the same reference numerals.

In the second embodiment according to FIG. 2, an external thread 56 is incorporated in the plastic casing at the connection end 42 of the fitting 10 '; the Werkzeugansetzabschnitt 52 continues to be made of plastic, as in the embodiment of FIG. 1.

In the embodiments according to FIGS. 3 and 4, the tool setting section 52 is designed as a circumferential radial projection 50 of the metal insert element 16. The plastic coating on the outside 24 of the wall 20 of the metal insert element 16 at the connection end 42 of the fitting 10 "ends, for example, on the circumferential radial projection 50. FIG. 3 shows a fitting 10" with internal thread 46 on the inside 44 of the plastic sheath of the connection end 42 while in Fig. 4, the fitting 10 "'has a plastic outer thread 56

In the embodiments according to FIGS. 3 and 4, the integral connections between the inner and outer plastic material layers via the recesses 54 may be designed as shear pins which shear off at a defined torque. Axial forces can then be transmitted via a peripheral circumferential toothing (not shown) on the inner and / or outer side of the Metalieinsatzelements 16 between plastic and metal- In the embodiments Maß measure the Fign. 1 and 2, in which the Werkzeugansetzabschnitte 52 made of Kunststoffmateriai, a shearing connection and thus a solid to a defined torque connection by shearing the circumferential radial projection 50 (or a part thereof) may be realized to the radially adjacent portion.

Claims

1. Fitting for a pipe, in particular for a pipe having a plastic layer on its inside, with a fitting body (15) which has plastic material and is provided with at least one connection region (36) for the pipe, and at least one tubular passage section (18 ) which is at least partially enclosed by the plastic material of the fitting body (15), the tubular passage section (18) having on its inside (22) a plastic material layer (28) which surrounds at least one axial end (26). the tubular passage section (18) is guided around and extends into the outer side region (24) of the tubular passage section (18) adjacent to the end (26), and wherein the at least one connection region (36) of the plastic material I läge (32) on the Outer side portion (24) of the tubular passage portion (18) is formed,

2. Fitting according to claim 1, characterized in that the metal insert element (16) has a plurality of tubular passage sections (18) and in that on the axial ends (26) of all tubular passage sections (18) adjacent outer side regions (24) is plastic material.

3. Fitting according to claim 1 or 2, characterized in that in the plastic material layer (32) within the at least one or within each connection region (36) at least one receiving groove (38) is formed with a sealing ring (40) arranged therein.

4. Fitting according to one of claims 1 to 3, characterized in that the metal insert element (16) is provided with from the outside (24) of the tubular passage portion (18) to the inside (22) extending perforations (54), which were (28,32) on the inside and outside (22,24) of the tubular passage portion (18) filled with plastic material for the connection of the Kunststoffmateria,

5. Fitting according to one of claims 1 to 4, characterized in that the or each provided with a plastic material layer (32) outer side region (24) of the tubular passage portion (18) has a structured surface for formschiüssigen connection with the Kunststoffmateria! having.

6. Fitting according to one of claims 1 to 5, characterized in that the Metaüeinsatzelement (16) on its surface a toothing or projections for receiving between the tubular passage portion (18) and the Kunststoffmateria I läge (28,32) acting axial forces ,

7. Fitting according to one of claims 1 to 6, characterized in that the fitting body (15) has a connection end (42) for connecting the fitting body (15) to a media-carrying unit, that an axial end of the tubular passage portion (18) of the Metal insert element (16) extends into the terminal end (42) of the fitting body (15) and in that the connection end (42) of the fitting body (15) from lying on the inside and the outside and around the axial end of the tubular passage portion (15). 18) guided around plastic material is formed.

8. Fitting according to claim 7, characterized in that the connection end (42) of the fitting body (15) has an inserted into the plastic material inner and / or outer thread (46,56).

9. Fitting according to claim 8, characterized in that the fitting body (15) has a Werkzeugansetzabschnitt (52) on which a tool for connecting the fitting body (15) with a media-carrying unit can be attached and that the Werkzeugansetzabschnitt (52) as part of Metalieinsatzelements (16) or made of Kunststoffmaterϊal is formed.