socket system

Abstract

Coupling system (10) for a plastic protective pipe (40), with a sleeve (20) for welding to the plastic protective tube (40); a clampable compression seal (30) with an elastomer body (31); wherein the compression seal (30) is arranged or can be arranged in the sleeve (20), and wherein the compression seal (30) can be clamped in the sleeve (20) in such a way that the elastomer body (31) seals itself radially outwards towards the sleeve (20).

Description

[0001] The present invention relates to a socket system for mounting on a plastic protective pipe.

[0002] The plastic protective conduit can, for example, be laid underground, with the actual cable then being laid or already contained within the conduit. The plastic protective conduit serves to protect the cable. It can also, for example, allow for future cable replacement without extensive excavation work. As explained in detail below, a preferred application is in cable routes, such as the installation of high-voltage or extra-high-voltage lines. This is intended to illustrate a possible application, but does not initially limit the scope of the subject matter.

[0003] The present invention addresses the technical problem of providing an advantageous system for a plastic protective tube. This is solved by the combination of features according to claim 1, namely a socket for welding to the plastic protective tube and a compression seal that can be clamped in the socket. The plastic welding connection of the socket to the plastic protective tube creates, for example, a robust and leak-proof connection to the plastic protective tube, while the socket also provides a defined environment for the compression seal.

[0004] If the compression seal were inserted directly into the plastic protective tube, only lower pressures could be reliably and reproducibly sealed. The sleeve welded to the plastic protective tube, in contrast, can withstand higher clamping forces (e.g., by having thicker walls) and / or provide means for additional axial fixation of the compression seal; see details below.

[0005] Preferred embodiments are found throughout the disclosure and particularly in the dependent claims, whereby the description of the features does not differentiate in detail between the different claim categories. In particular, all features explained in the context of the "socket system" should always also be read with regard to a "pipe system" with such a socket system.

[0006] The clampable compression seal has an elastomer body which, when clamped, is pressed against the sleeve to create a seal. For this purpose, the elastomer body can be compressed axially, causing it to seal radially outwards. Specifically, a surface of the elastomer body can be pressed radially outwards against an inner wall surface of the sleeve; preferably, the outer surface of the elastomer body can then rest against the inner wall surface. As explained in detail below, the compression seal can have clamping elements, such as clamping plates, on the axially opposite end faces of the elastomer body, which can be clamped together (e.g., using one or more clamping bolts).

[0007] Preferably, the compression seal is designed not only as a closure but also to seal against a pipe routed through it. In other words, it seals radially outwards towards the socket and radially inwards against a pipe routed within the plastic protective tube.

[0008] The "elastomeric material" of an elastomer body is, generally speaking, a plastic with elastic properties. Its Shore hardness (Shore A) can be, for example, a maximum of 90 Shore, 80 Shore, 75 Shore, or 70 Shore, and (independently of this) a minimum of, for example, 20 Shore, 25 Shore, or 30 Shore. It can be, for example, a rubber or synthetic rubber material, such as EPDM, or a thermoplastic elastomer (TPE) or a silicone-based material, e.g., silicone elastomer.

[0009] In general, within the context of this disclosure, the terms "axial," "radial," and "circumferential," as well as their associated directions (axial direction, etc.), refer, for example, to a central axis of the socket, which may be located centrally as a longitudinal axis within an internal volume formed by the socket. When mounted on the plastic protective tube, this central axis may, for example, coincide with a longitudinal axis of the plastic protective tube; a cable laid within the plastic protective tube may, for example, extend substantially parallel to the central axis.

[0010] As mentioned earlier, the socket can have a thicker and / or stiffer wall compared to the plastic protective tube; for example, a stiffening element can be incorporated into or attached to the socket. In other words, the socket can react to a radial force with less deformation than the plastic protective tube. Alternatively or additionally, an element or means for axially fixing the compression seal can be provided, which, for example, prevents the compression seal from slipping out axially.

[0011] The connection between the socket and the plastic protective tube can advantageously be achieved by welding, which allows, for example, a relatively large and therefore stable connection surface to be created. Friction welding or similar processes are also generally conceivable; however, in a preferred embodiment, the socket is designed as an electrofusion socket or incorporates one. The electrofusion socket preferably has an integrated heating coil, for example, made of wire, which can be heated by an electric current. This heat input allows an inner wall surface of the socket and an outer wall surface of the plastic protective tube to be locally melted or fused together, thus creating a metallurgical bond.

[0012] Regardless of the connection strength, electrofusion couplings can also be advantageous in specific application environments. For example, with buried plastic conduits that are only accessible to a limited extent or for a limited time, electrofusion couplings allow for relatively quick and precise installation of the coupling system onto the conduit. Compared to methods such as gluing, installation time can be reduced, and no additional materials may be required. Power can be supplied relatively easily with a local power source that can be moved from joint to joint, for example, when laying a pipeline (see details below).

[0013] Generally, the socket body of the coupling is preferably made of a plastic material, into which, for example, the heating coil can be embedded. The coupling itself can be a single piece or multi-part, as detailed below. The plastic material of the coupling or of an individual coupling part can be, for example, a rigid plastic with a Shore hardness (D) of at least 50, 60, or 70 Shore (with possible upper limits of, for example, 90, 85, or 80 Shore). Possible materials include, for example, acrylonitrile butadiene styrene (ABS), polypropylene (PP), or polyethylene (PE).

[0014] Regardless of the details of the socket, the plastic protective tube can also preferably be made of a rigid plastic, cf. for example the Shore values ​​mentioned above. The plastic protective tube can also be multi-layered, e.g., having a PE core in combination with one or more additional layers.

[0015] In a preferred embodiment, the socket has different diameters in sections. In other words, the socket can be designed as a reducer, with the smaller diameter section being welded to the plastic protective tube. In particular, a first socket section intended to receive the compression seal can have a different diameter than a second socket section intended for welding to the plastic protective tube, preferably a larger diameter. Specifically, this can refer to the inner diameter of the socket, which can therefore be larger in the first socket section than in the second. This allows a proportionally larger compression seal to be fitted to the socket, relative to the actual pipe diameter, which can offer advantages, for example, in terms of stability and / or handling.

[0016] In a preferred embodiment, the socket has a radially rising mounting section for axially fixing the compression seal. This section can generally also rise radially inwards, thus forming, for example, a stop for the compression seal. In this case, the compression seal can already be positioned in the socket when the socket is welded to the plastic protective tube.

[0017] In a preferred embodiment, the mounting section extends radially outwards, allowing the compression seal to be installed, for example, after the socket has been welded to the plastic protective tube (or alternatively, already installed). Generally, the mounting section can preferably be designed as a circumferential flange, particularly as a fully enclosed flange. In addition to providing a mounting option, this can offer further stabilization. Therefore, the socket is preferably equipped with an outer flange, for example, at its end axially opposite the welded joint. In general, the outer flange can also serve, for example, to mount a reducing washer, which then acts as a stop for the compression seal.

[0018] According to a preferred embodiment, the compression seal has a first clamping element which is arranged on one end face of the elastomer body for clamping it. The clamping element can, for example, be a clamping plate, such as a metal clamping plate. Regardless of these details, the clamping element is preferably designed to be connectable to, or connected to, the fastening section. Preferably, the first clamping element has a larger outer diameter than the elastomer body; in other words, the clamping element has a radial projection relative to the elastomer body, and it is connected to the fastening element or flange in the region of this radial projection. In particular, a clamping plate, preferably made of metal, can have a radial projection and be connected to the fastening section, preferably to an outer flange of the sleeve.

[0019] The connection between the fastening section and the clamping element is preferably a screw connection. Several screws can be provided, for example, distributed around the perimeter.

[0020] The mounting section or outer flange can, for example, be made of plastic, with an additional counter bearing arranged on a side of the flange axially opposite to the first clamping element. This counter bearing can, for example, be a metal ring, such as a completely closed ring. Threads for the clamping bolts can be cut into the ring, or alternatively, the bolts can pass through it, serving as a counter bearing for nuts guided on the bolts.

[0021] As mentioned at the outset, in a preferred embodiment, the compression seal has a second clamping element on the axially opposite side of the elastomer body. In the assembled state, this second clamping element and the elastomer body are then positioned, for example, axially within the sleeve. The compression seal can further include a clamping bolt by means of which the clamping elements can be clamped axially relative to each other. This allows the elastomer body to be compressed axially and thus pressed radially outwards against the inner wall surface of the sleeve and, preferably, radially inwards against the pipe. Preferably, the clamping bolt passes through the elastomer body.

[0022] Generally, "a" and "an" within the context of this disclosure are to be read as indefinite articles and thus, unless expressly stated otherwise, always as "at least one" or "at least one". For example, several clamping bolts may be provided, each of which penetrates the elastomer body and clamps the clamping elements or plates against each other.

[0023] Within each end face, the clamping element can also be divided, i.e., it can have several clamping element parts, in particular clamping plate parts. Optionally, the elastomer body can also be partially slotted in such a way that it can be opened and placed radially onto the pipe, thus enabling installation even on an already installed pipe.

[0024] According to a preferred embodiment, the sleeve comprises a first and a second sleeve part, wherein the electrofusion sleeve is preferably the second sleeve part. The first sleeve part can then, for example, be provided with the fastening section, and in particular, it can be designed as a flange part with the flange. The fastening section, in particular an outer flange, is preferably provided at one end of the first sleeve part; at the axially opposite end, the first sleeve part can be connected to the electrofusion sleeve.

[0025] The first and second socket sections can be separate parts before being welded to the protective tube. A weld connection can be made to both the first socket section and the plastic protective tube via the electrofusion socket, preferably in the same assembly step. In other words, the first socket section can be inserted into the electrofusion socket from one axial side, and the plastic protective tube can be inserted into the electrofusion socket from the axially opposite side. By applying the current (see above), the electrofusion socket is simultaneously welded to the first socket section and the plastic protective tube. This variant can be advantageous, for example, because an electrofusion socket intended for joining pipes can be used to connect or manufacture the socket.

[0026] A preferred embodiment relates to a pipe system which, in addition to a socket system disclosed herein, has a plastic protective pipe. Here, the socket is welded to the plastic protective pipe, preferably in the form of an electrofusion socket (see above for details).

[0027] The plastic protective tube can, for example, have an inner diameter of at least 15 cm, 20 cm, or 25 cm, with possible upper limits of, for example, 50 cm or 40 cm. Regardless of the specific dimensions, its wall thickness can also be in the centimeter range, for example, at least 0.5 cm, 1 cm, or 2 cm (with a possible upper limit of, for example, 4 cm).

[0028] The socket is preferably located at one end of the plastic protective tube, and is particularly preferably welded onto the plastic protective tube. In other words, the welded joint is formed between a radially outward-facing outer wall surface of the plastic protective tube and a radially inward-facing inner wall surface of the socket. The welded joint preferably extends circumferentially and can, for example, extend axially over a minimum of 1 cm, 2 cm, 3 cm, 4 cm, or 5 cm (with possible upper limits of, for example, a maximum of 50 cm, 40 cm, or 30 cm).

[0029] In a preferred embodiment, a conductor is laid within the plastic protective tube, preferably passing through the elastomer body of the compression seal. The compression seal is preferably clamped, so that the elastomer body seals an internal volume of the plastic protective tube. In other words, the elastomer body can seal the conductor to the socket and thus also to the plastic protective tube.

[0030] In general, the conduit can also be a fluid line, which in turn carries a medium inside, such as gas or a liquid. A natural gas or district heating pipeline is one example. Preferably, however, the conduit is a cable, in particular an electrical cable. The electrical cable can be a high-voltage or extra-high-voltage line, i.e., designed for a voltage in the kilovolt range. Specifically, the voltage class can be, for example, at least 50 kV, preferably at least 100 kV, with several hundred kV also possible (upper limits can be, for example, 800 kV or 600 kV).

[0031] According to a preferred embodiment, the internal volume of the plastic protective tube is filled with a non-gaseous fluid, e.g., a viscous liquid. The fluid can preferably be a hydraulic filler, e.g., a cable gel with bentonite. The filling can, for example, create a defined thermal connection, even in the case of varying thermal resistance in the soil along the length of the plastic protective tube (e.g., lower resistance in gravel, etc.). The socket system can be advantageous insofar as, for example, comparatively high pressure loads can occur in hilly terrain with a corresponding gradient. These can be reliably absorbed by the combination of a welded connection and a tensioned, in particular axially fixed, compression seal.

[0032] According to a preferred embodiment, the compression seal has a filling port through which the non-gaseous fluid can be introduced into the inner volume of the plastic protective tube. The filling port can, for example, penetrate the elastomer body and open into the inner volume; preferably, it is equipped with a shut-off valve. In addition to the filling port, there can, for example, be a vent port through which air can escape from the inner volume during filling. This vent port can also be equipped with a shut-off valve.

[0033] A preferred embodiment relates to a socket system with a first and second socket section (see above), wherein the first socket section is connected to the plastic protective tube via the electrofusion socket, i.e., welded. Generally, the first socket section can also be attached relative to the electrofusion socket in another way, but preferably it is also welded to it. In other words, the electrofusion socket is then welded to both the first socket section and the plastic protective tube.

[0034] According to a preferred embodiment, a further plastic protective tube is provided, which follows the (first) plastic protective tube axially. At a joint, the two plastic protective tubes can face each other with their abutting ends (with a distance of, for example, 0.3–3 m, in particular 0.8–2 m), and the pipeline can extend through the protective tubes (but may also have a connection point at the joint itself). Preferably, a plurality of plastic protective tubes can be arranged successively along the pipeline route, with each plastic protective tube having a length of, for example, at least 0.1 km, more preferably at least 0.5 km or 1 km, with possible upper limits of, for example, a maximum of 4 km, 3 km, or 2 km.

[0035] Furthermore, a method for manufacturing a pipe system is disclosed in which the socket of the socket system is welded to the plastic protective pipe, preferably as an electrofusion socket by applying an electric current. For further possible details, reference is made to the preceding disclosure. The use of a socket system disclosed herein for welding to a plastic protective pipe is also disclosed; see further details above.

[0036] The invention will now be explained in more detail using an exemplary embodiment, whereby the individual features may also be relevant in other combinations.

[0037] In detail, it shows Fig. 1 a plastic protective tube with a welded socket system in a schematic longitudinal section; Fig. 2 an electrofusion coupling in a single illustration; Fig. 3 a compression seal with a pipe passing through it; Fig. 4 a plastic protective tube with a welded socket system in a schematic longitudinal section; Fig. 5 a pipe system in a first installation situation; Fig. 6 a pipe system in a second installation situation.

[0038] Fig. Figure 1 shows a socket system 10, which includes a socket 20 and a compression seal 30. The socket 20 is mounted on a plastic protective tube 40 and welded to it. Specifically, the weld 41 is formed between an outer wall surface of the plastic protective tube 40 and an inner wall surface of the socket 20, see Figure 1. Fig. 2 with further details.

[0039] A conductor 50, namely a high-voltage cable 51, is installed in the plastic protective tube 40. The compression seal 30 has an elastomer body 31 which, when clamped, seals radially inwards against the conductor 50 and radially outwards against the sleeve 20. A first clamping element 35 is provided on one end face of the elastomer body 31 for clamping, and a second clamping element 36 is provided on the axially opposite end face. When the clamping elements 35 and 36 are clamped axially relative to each other, the elastomer body 31 is compressed and thus pressed radially inwards and outwards.

[0040] The compression seal 30 is arranged in a first socket section 21 of the socket 20, and the welded joint 41 is formed in a second socket section 22. In the present example, the first socket section 21 has a larger diameter than the second socket section 22.

[0041] The sleeve 20 further comprises a fastening section 25 that extends radially outwards. In this case, the fastening section 25 is designed as a circumferentially closed flange 26. The first clamping element 35 has a radial projection relative to the elastomer body 31 and is screwed to the flange 26 27.

[0042] Fig. Figure 2 shows the socket 20 in detail; in this case, it is designed as an electrofusion socket 120. Generally, within the scope of this disclosure, the same reference numerals denote the same parts or parts with the same function, and reference is therefore also made to the descriptions of the respective other figures. A heating coil 28 is embedded in the second socket section 22, to which a current can be applied via terminals 28.1, 28.2. As a result of the heating, an inner wall surface 22.1 of the socket 20 and the outer wall surface of the plastic protective tube (not shown here) are melted and thus welded together.

[0043] Fig. Figure 3 shows the compression seal 30, which relates to Fig. The clamping elements 35 and 36 can be inserted into the first socket section 21 from the right (before or after welding the socket). The clamping elements 35 and 36 are operatively connected to each other via clamping bolts 37. These bolts penetrate the elastomer body 31 and allow axial clamping, as a result of which the elastomer body 31 presses radially inwards against the pipe and radially outwards against the socket (not shown).

[0044] Fig. Figure 4 shows a socket system 10 in which the socket 20 comprises a first socket part 20.1 and a second socket part 20.2. The latter is an electrofusion socket 120, which together with the first socket part 20.1 forms the socket 20. The fastening section 25 or flange 26 is provided on the first socket part 20.1, specifically at an axial end opposite the second socket part 20.2.

[0045] In this case, both the plastic protective tube 40 and the first socket part 20.1 are inserted into the second socket part 20.2. In other words, the plastic protective tube 40 extends into the second socket part 20.2 from one axial side, while the first socket part 20.1 extends into the second socket part 20.2 from the axially opposite side. The two are connected to each other via the second socket part 20.2, i.e., the electrofusion socket 120. A weld connection 41 to the plastic protective tube 40 and a weld connection 141 to the first socket part 20.1 are formed. These weld connections 41 and 141 can be made simultaneously.

[0046] Fig. Figure 5 shows a schematic representation of a pipe system 60 in an installed state. The plastic protective pipe 40 is buried in the ground, and another plastic protective pipe 140 connects to it axially. The socket system 10, shown only schematically here, is shown in Figure 5. Fig. 1 or Fig. 4 Regarding possible details, an internal volume 45 of the plastic protective tube 40, which in this case is filled with cable gel 46, is sealed. The cable 50, connected via a coupling 55, continues in the further plastic protective tube 140. Its internal volume is sealed with a sleeve system 110. There can be a large number of such joints 65 along the cable route.

[0047] Fig.Figure 6 illustrates a situation with a slope in the terrain; the plastic protective pipe 40 therefore has an incline. Accordingly, the cable sleeve 46 is under pressure against the socket system 10 or its compression seal, e.g., several bar. The socket system can withstand this pressure due to the combination of welded connection and axial fixation.

Claims

[1] Coupling system (10) for a plastic protective pipe (40), with a sleeve (20) for welding to the plastic protective tube (40); a clampable compression seal (30) with an elastomer body (31); wherein the compression seal (30) is arranged or can be arranged in the sleeve (20), and wherein the compression seal (30) can be clamped in the sleeve (20) in such a way that the elastomer body (31) seals itself radially outwards towards the sleeve (20). [2] Coupling system (10) according to claim 1, wherein the coupling (20) is or comprises an electrofusion coupling (120). [3] Coupling system (10) according to claim 1 or 2, wherein the coupling (20) has different diameters in sections. [4] Sleeve system (10) according to claim 3, in which the elastomer body (31) of the compression seal (30) is arranged in a first sleeve section (21) and a second sleeve section (22), which has a smaller diameter in relation to the first sleeve section (21), is provided for welding to the plastic protective tube (40). [5] Sleeve system (10) according to one of the preceding claims, wherein the sleeve (20) has a radially rising fastening section (25) for axial fixation of the compression seal (30). [6] Sleeve system (10) according to claim 5, in which the fastening section (25) extends radially outwards. [7] Sleeve system (10) according to claim 5 or 6, wherein the fastening section (25) is provided as a flange (26). [8] Sleeve system (10) according to one of claims 5 to 7, wherein the compression seal (30) has a first clamping element (35) which is arranged to clamp the elastomer body (31) on an end face of the elastomer body (31), wherein the first clamping element (35) can be connected to or is connected to the fastening section (25). [9] Sleeve system (10) according to claim 8, in which the clamping element (35) and the fastening section (25) are screwed together. [10] Sleeve system (10) according to claim 8 or 9, in which the compression seal (30) has a second clamping element (36) on the opposite end face of the elastomer body (31) and a clamping bolt (37) connecting the clamping elements (35, 36) to each other, by means of which the clamping elements (35, 36) can be clamped axially to each other. [11] Coupling system according to one of claims 5 to 10 in conjunction with claim 2, wherein the fastening section (25) is arranged on a first coupling part (20.1) and the electrofusion coupling (120) is a second coupling part (20.2). [12] Pipe system (60), with a plastic protective tube (40); a socket system (10) according to one of the preceding claims; wherein the socket (20) is welded to the plastic protective tube (40). [13] Pipe system (60) according to claim 12, wherein the socket (20) is welded to one end of the plastic protective pipe (40). [14] Pipe system (60) according to claim 12 or 13, in which a line (50) is laid in the plastic protective tube (40) which penetrates the elastomer body (31) of the compression seal (30). [15] Pipe system (60) according to claim 14, in which the compression seal (30) is clamped and the elastomer body (31) seals an inner volume (45) of the plastic protective tube (40). [16] Pipe system (60) according to claim 15, in which the internal volume (45) of the plastic protective tube (40) is filled with a non-gaseous fluid (46). [17] Pipe system (60) according to one of claims 12 to 16, in which the compression seal (30) has a filling nozzle through which a non-gaseous fluid (46) can be introduced. [18] Pipe system (60) according to one of claims 12 to 17, with a socket system according to claim 11, wherein the first socket part (20.1) is connected to the plastic protective pipe (140) via the electrofusion socket (120). [19] Pipe system (60) according to claim 18, in which the electrofusion coupling (120) is welded to the first coupling part (20.1) and to the plastic protective tube (140). [20] Pipe system (60) according to one of claims 12 to 19, comprising a further plastic protective tube (140); in which the line continues from the end of the plastic protective tube (40) into the further plastic protective tube (140), wherein a further socket system (110) is arranged at the end of the further plastic protective tube (40).

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