SK9493A3 - Packing ring for a connection with slided sleeve - Google Patents

Abstract

The sealing ring (1) is suitable for use for a plug-in sleeve connection in the region of tubular elements. The sealing ring is formed from at least one elastomer. At least one sliding means is added to the elastomer and is arranged, such that it can change its position, inside the mixture (2) resulting from the mixing procedure. At least during part of a period of use time provided, the sliding means escapes from a surface of the sealing ring (1), produced from the mixture (2), to form a sliding film. <IMAGE>

Description

Technical field

The present invention relates to a sealing ring for connection by a push-on sleeve in tubular-shaped bodies which is formed of at least one elastomer.

BACKGROUND OF THE INVENTION

Such sealing rings are widely used to seal joints with a slip sleeve, which are located at the ends of pipes or fittings formed by T-pieces or branches. Depending on the application envisaged, the sealing rings have different shapes, in particular flap seals and seals with a circular cross-sectional area are known. These sealing rings are mounted in the sleeve end in a groove recess or notch, which are formed substantially concentrically in the inner wall of the slip sleeve. However, it is also possible to form a notch on the outer surface of the part which is inserted into the sleeve.

Both the insertion of the sealing ring into the groove provided for this purpose and the insertion of the pipe into the sleeve and the desired adjustment of the sealing ring, there is a considerable problem with the frictional forces arising. These may result in the sealing ring being deformed or twisted, which may result in leakage or damage to the sealing ring. To reduce these frictional forces, a lubricant, which is usually a silicone oil or a soap-based substance, is applied to the surface of the produced sealing ring. This deposition can be carried out e.g. by spraying, soaking, rolling or drum processing. A method is also known in which the sealing ring is first mounted in a groove-like recess in which the glidant is applied and subsequently applied to its surface - e.g. brush - a slip to ensure a smooth fit.

It is known from DE 39 09 381 A1 to use gaskets of rubber or rubber-like substances for sealing the space between two pipes. For this purpose, a gasket is inserted in the sleeve end of one tube, which essentially consists of a sealing ring and a band-shaped sliding ring, the sliding ring being slidable on the sealing ring by means of sliding means and the sliding ring having a PTFE or polyamide film layer. It is also possible to use liquid or paste glidants which are applied to the surface of the slide ring.

DE 38 17 868 A1 discloses a sealing ring which can be fitted between coaxially arranged surfaces. In order to facilitate the displacement of the sealing ring, a lubricant is applied which is applied to the sliding surfaces, the internal displacement which is made possible by the interaction of the two sealing parts is described. The first and second sealing portions are arranged to be positionable relative to one another.

A further sealing ring is described in DE 29 00 437 A1 and is also intended for use between two concentric surfaces. The sealing ring has two sliding surface sealing sections that contact in the sliding surface area. A lubricant or glidant that is applied to the sliding surfaces may be used to improve the sliding effects.

DE 88 06 952 U1 discloses a seal for precast concrete which may have flaps. A glidant that reduces the frictional forces when applying the seal is at this stage supplied to the seal by means of a rubber hose.

However, these known solutions have several drawbacks. Glidant dosing is often inaccurate, and especially if this is done by ancillary staff, it should be expected that too much expensive glidant will be applied. When impregnating the sealing rings with a glidant prior to use, there is a problem of how to dispose of the packing ring packing material which is contaminated with the glidant is environmentally sound. In addition, some of the sliding means cause spots to occur when applied manually.

SUMMARY OF THE INVENTION.

The present invention is directed to a seal ring design which will guarantee sufficient sliding properties and eliminate the drawbacks resulting from the use of separate sliding means.

The solution according to the invention is characterized in that the sealing ring is made of an elastomer-based compound to which at least one glidant is added in the mixing process, which is distributed almost uniformly in the compound by stirring and at least during a part of the intended use. on the surface of the sealing ring and forms a sliding film thereon.

With such a sealing ring, it is already provided in its manufacture that it will have the desired sliding properties when applied later and therefore it is not necessary to secure them before or during use of the sealing ring. There are also no problems with the accuracy of the lubricant dosing. The advantages of such a solution are manifested not only when fitting the sealing ring into the notch, but also when connecting with a slip-on sleeve, whereby the ease of assembly is evident in both the automatic and manual assembly processes. The frictional forces between the sealing ring and the pipe are greatly reduced, so that a defined slip of the ring along the pipe as well as a defined notch passage is guaranteed and these properties are retained even for more complicated ring geometry.

Integration of the glidant into the elastomer prevents both insufficient dosing of the glidant, which leads to insufficient gliding, and overdose, which leads to the accumulation of excess glidant. (The known gaskets deteriorate after some time after the addition of the lubricant due to diffusion of the lubricant into their volume. On the other hand, due to the ability of the lubricant to exit the elastomer into which it is admixed, the lubricant forms When making a slip sleeve connection, another advantage is evident in that the sliding means does not settle on the outer surface of the pipe or fitting and is transferred to the vicinity of the slip sleeve connection. The application of silicone oil in the area of settling surfaces shows insufficient adhesion of the subsequent coating.

By integrating the glidant into the elastomer, it is defined to protrude onto the surface of the seal ring, making it substantially impossible to lose it. Precise dosing of the glidant results in material savings, which leads to a reduction in the cost of using sealing rings. In addition, there are no additional work steps that have followed the production of known types of sealing rings, which leads to a reduction in labor and investment costs.

When using a compound that undergoes heat crosslinking, it is proposed that the elastomer be a vulcanizable elastomer.

A compound which undergoes crosslinking when the temperature decreases is prepared by using a thermoplastic elastomer as the elastomer.

A particularly effective solution is when the glidant is an unsaturated organic fatty acid amide.

Oleic acid amide is proposed as a glidant for use in drinking water supply systems.

A gasket with a sufficiently good sliding film is prepared from a blend containing from 1 to 10 parts by weight of glidant per 100 parts by weight of elastomer.

A good compromise between the satisfactory gasket properties of the O-ring and the minimum consumption of glidant is achieved by using a blend consisting of 100 parts by weight of elastomer mixed with 3 to 7 parts by weight of glidant.

A uniform and long-term sliding film formation is achieved when the distribution of the sliding agent in the elastomer is substantially homogeneous.

For the production of sealing rings intended for standard applications, it also suggests that the compound is formed in the form of sealing rings for pipes and fittings with standardized notch geometry.

Further areas of possible application of the sealing rings according to the invention arise when the compound is formed into a sealing ring shape for special notch geometry in which the notch is formed from jointly combinable elements. In addition, it is also contemplated that the compound is formed into a sealing ring suitable for a variable notch.

In order to achieve effective sealing effects, it is proposed that the compound is formed into a flap seal.

It is also possible for the compound to be formed into a shape of a sealing ring, the cross-sectional area of which has a circular shape at least over a portion of the periphery.

The advantages of certain gasket geometries can be combined such that the compound is formed into a seal ring having at least one flap and at least one circular cross-sectional area at the same time.

Overview of the figures in the drawing

Embodiments of the invention are illustrated schematically in the accompanying drawings which represent:

Fig. 1 - cross section of the sealing ring, which also contains the tensioning ring, Fig. 2 - partial cross-section of the pipe with the shape of the sleeve with the notch in which the flap seal is inserted, Fig. 3 - principal representation of the sealing ring with circular Fig. 4 is a cross-sectional view of the notch with another lip of the valve, Fig. 6 - another sealing ring, Fig. 4 shows a sealing ring with a flap, which also includes a tensioning ring and is inserted into the notch; Fig. 7 is a cross-sectional view of a notch with an inserted sealing ring and a tensioning ring; Fig. 8 is a flow diagram illustrating the process of manufacturing a sealing ring; Fig. 9 is a cross-section of a pipe whose notch for sealing ring is formed from two elements, each element bounding the notch.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

The sealing ring 1 used in the connection by means of a sliding sleeve consists of one or more elastomers to which one or more sliding means is admixed. A sealing ring 11 is formed from the compound 2 formed by mixing the elastomer and the glidant by compression, molding or injection molding. Referring to FIG. 1, the sealing ring 1 can be formed as a sealing ring with a flap having, in addition to the flap 3, a circumferential profiling 4 and a central groove 5 in which the tensioning ring 6 is provided.

Example 2

According to FIG. 2, the sealing ring 1 is inserted into a notch 7 of a pipe 8, which may be of plastic, stoneware, cast iron or concrete. Instead of the structure shown in the figure, the notch 7 may be located on the fittings which are slid onto the tubular elements and thereby allow the joining of large numbers of tubes 8. In this way, it is possible to implement water, sewage or household waste systems. In addition, the pipes 8 thus connected can be used to form a protection of the electric lines or of the cables. protection of telecommunications cable routes.

Example 3

In addition to the sealing rings 11 with the flap 3, it is also possible, according to FIG. 3, to form a sealing ring 1 with a circular cross-sectional area 9. A special case of such a construction is an O-ring with a circular cross-sectional area 9.

Example 4

According to FIG. 4, it is possible to realize a combination of a circular cross-sectional area 9 and a flap 3, whereby a tension ring 6 can be inserted into the sealing ring 1.

Example 5

In addition to forming the sealing ring 7 from a single elastomer, respectively. 5, it can also be formed from a plurality of interdependent parts made of different elastomers according to FIG. In principle, it is possible to use a different proportion of glidant or glidant in each of the elastomers. use different substances as a glidant. With a suitable combination of materials it is possible to ensure the long-term maintenance of good sliding properties and, in particular, to cover a larger temperature range, while various combinations of elastomers and sliding means can be applied to any geometry of the sealing ring 1. .

Both the elastomers used and the glidants may have different chemical properties. As elastomers, e.g. rubber vulcanizable elastomers or thermoplastic elastomers. For vulcanizable elastomers, cross-linking occurs as a result of elevated temperature and pressure, while thermoplastic elastomers are subjected to a temperature decrease after previous melting. As vulcanizable elastomers, e.g. elastomers of SBR, EPDM, IR, CR, NBR, HNBR, ACU, IIR or NR, respectively. suitable combinations thereof. Examples of thermoplastic elastomers include S-EB-S and PUR. In principle, all substances which exhibit the desired sliding properties and are suitable for elimination from the elastomer can be used as glidants. In particular, amides of unsaturated fatty acids have proven to be successful. The use of oleic anhydride is particularly preferred, but lauramide, stearol amide or eurecic acid amide may also be used.

Example 6

The block diagram of FIG. 8 illustrates the process of manufacturing and using the sealing ring 1. The inlets of the elastomer 10, the additive 11 and the sliding means 12 are fed to the mixing device 16. The mixing process can be carried out e.g. such that 1 to 10 parts by weight of glidant 12 are added to 100 parts by weight of elastomer 10, with 3 to 7 parts by weight of glidant 12 being particularly suitable. After sufficient heating and mixing of the inlets, the mixed material 2 is fed in the cooled state in the form of extruded strips or granules to the molding machine 17, where the sealing rings 1 are formed therefrom. the push-on sleeve connections are assembled.

Example 7

The notch Z into which the sealing ring 1 is inserted can also be formed as a combination of two components. In particular, according to FIG. 9, the notch 7 is defined by the pipe end 20 and the closure ring 21. Thus, the sealing ring 1 can be fitted to the end of the pipe before the closing ring 21 is inserted and then fixed by joining the pipe end 20 and the closing ring 2.1 (so-called click-coupling). The sealing ring X is a positive fit

very tightly fixed in the notch 7. Example 8 A1ternatívne to still described separately by from taking a sealing ring 1 and his subsequent betting into notch 7 is

it is also possible to introduce the compound 2 directly into the notch 7 and only here to form the desired shape of the sealing ring χ by means of a mold. When using plastic pipe seals, these can be normalized to standardized notch geometry and made e.g. made of PP, PVC, PE or ABS.

Example 9

As an alternative to forming the sealing ring X into a final shape, it is also possible to produce a linear sealing profile and to make it into the desired shape of the sealing ring X by gluing or subsequent crosslinking. The linear sealing profile can be produced in the desired lengths.

Claims (12)

PATENT CLAIMS O-ring for a sleeve connection in tubular-shaped bodies which is formed of at least one elastomer, characterized in that at least one sliding means is admixed in the elastomer and is dispersed in a volume of the compound (2) formed by mixing and at least during a portion of the intended period of use forms a sliding film protruding from the surface of the sealing ring (1) made of the compound (2). 2. The sealing ring according to claim 1, wherein the elastomer is formed as a curable elastomer. 3. The sealing ring of claim 1, wherein the elastomer is a thermoplastic elastomer. Sealing ring according to one of Claims 1 to 3, characterized in that the glidant is an unsaturated organic fatty acid amide. Sealing ring according to one of Claims 1 to 4, characterized in that the glidant consists of oleic acid amide. Sealing ring according to one of Claims 1 to 5, characterized in that 1 to 10 parts by weight of glidant are admixed to 100 parts by weight of the elastomer. Sealing ring according to claim 6, characterized in that 3 to 7 parts by weight of glidant are admixed to the elastomer. O-ring according to one of Claims 1 to 7, characterized in that the sliding means is distributed substantially homogeneously in the elastomer. O-ring according to one of Claims 1 to 8, characterized in that the O-ring (1) is shaped for pipes or fittings with normalized notch geometry. O-ring according to one of Claims 1 to 9, characterized in that the O-ring (1) is designed for special notch geometries in which the notch (7) is formed by a combination of structural elements with one another. O-ring according to one of Claims 1 to 8, characterized in that the O-ring (1) is designed for a variable notch. 12. Sealing ring by one from points 1 until 11 characterized by being sealed ring (1) has seal shape with valve. 13. Sealing ring according to one of points 1 v a z 12 characterized by being sealed ring (1) has at least v part circular range the transverse surface (9) cut. 14. Sealing ring by one of points 1 until 10. characterized characterized in that the sealing ring (1) has both at least one flap (3) and at least one circular flat (9) cross-section.