DE8715620U1 - Device for coupling coolant-carrying flow pipes - Google Patents

Description

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■'· v'orr i-_ jtung ^. around coupling of coolant-carrying flow pipes"

The innovation concerns a device for coupling coolant-carrying flow pipes.

Current pipes that are used to conduct strong electrical currents and are exposed to considerable heating due to the high current density are cooled by coolants, in particular cooling liquid, that flow through the current pipe. Coupling devices for such current pipes, which are used, for example, in connection with electric arc melting furnaces, must therefore connect the two current pipes to be coupled in a fluid-tight manner on the one hand and, on the other hand, have as low an electrical resistance as possible in order to enable a low-loss current transmission from one current pipe to the other current pipe.

Up to now, such coupling devices have mainly been designed in the form of a material-locking, non-detachable connection between the flow pipes, or captive and non-detachable clamping sleeves have been chosen as flow pipe connectors.

From DE-OS 31 27 633 a device for coupling two coolant-carrying flow pipes is known, which combines sufficient tightness with good electrical contact and should be detachable at any time with a simple structure. For this purpose the flow pipes to be coupled are brought together at the front in a tight manner and are surrounded by a preferably elastic sleeve, which in turn is surrounded by a pressure sleeve, which

ar an outer cylinder sleeve and can be subjected to fluid pressure in order to firmly attach the inner sleeve to the surface of the

binding pipe ends. The cylinder sleeve &ogr;

is preferably welded to one end of one flow tube and the coupling connection is achieved by inserting the end of the other flow tube into the prepared cylinder sleeve, lined by a pressure sleeve and contact-making inner sleeve, and pressurizing the pressure sleeve.

However, this solution not only requires the constant provision of fluid pressure to ensure the coupling connection of the flow tubes, but also a special surface treatment of the contact surface of the inner sleeve and the flow tube ends. In addition, the sealing of the flow tubes at their

Front sides are problematic. Finally, this

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Clutch also no possibility, if necessary

to modify the coupling device so that position tolerances between the ends of the flow pipes or operational relative movements of the flow pipes can be taken into account.

From DE-OS 1410 170 a stuffing box fastening of a current pipe end to a contact jaw for the electrode of an arc melting furnace is known, whereby the stuffing box forms a sealing packing made of metal chips between the current pipe end and the receiving bore.

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which puts pressure on the contact jaw in order to achieve good contact on the one hand and, on the other hand, to seal the end section of the water-cooled high-current tube.

However, such a solution is unsuitable for connecting two flow pipes carrying coolant.

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The aim of the innovation is to provide a device of the type mentioned above which enables a quick, reliable and at any time detachable coupling of two flow pipes and connects them to one another in a coolant-tight manner with very low contact resistance.

This object is achieved according to the invention in that a conductive disc tube body is provided with at least one essentially axially projecting external thread flange, which has an inner section for receiving an end section of a current tube, with the external thread flange a fastening nut held on the current tube can be brought into engagement and an axially displaceable contact sleeve is provided, which is supported by the fastening nut on the external thread flange for press engagement with the end section of the current tube

is brought. 20

By means of a simple screw connection, which is preferably assigned to each of the flow pipe ends to be connected by the device according to the innovation

is, is thereby once by means of the disc-26

pipe body itself and the inner section of the external thread flange formed receptacle for the flow pipe end, as well as by the support on the external thread flange depending on

from the tightening torque of the fastening nut in clamp-30

The contact sleeve, which moves in engagement with the jacket surface of the flow tube, achieves an extraordinarily high level of tightness of the device against the escape of coolant, in particular coolant liquid, accompanied by a very good contact of

the end of a power pipe via the corresponding

Contact sleeve and the disc tube body onto the other current tube to be coupled.

g In a preferred embodiment of the innovation, the inner section of the external thread flange of the disc tube body which receives the flow tube end has a conical inner surface to form an inclined plane which, together with the associated flow tube surface, forms a tapered wedge-shaped annular gap in which the contact sleeve, which is moved axially by a union nut, is forced to move in the direction of the circumferential surface of the flow tube end to produce an intimate clamping or

notch contact with the end of the current pipe. 15

Preferably, the contact sleeve is made of a material that is harder than the material of the associated current tube, so that with appropriate contact pressure an inner ring end edge of the contact sleeve or sawtooth-shaped contoured inner sections thereof penetrate into the surface of the current tube end.

According to an advantageous further embodiment of the innovation, the sealing within the coupling and contact device is further improved in that at least one O-ring is accommodated within the inner section of the external thread flange of the disc tube body.

An increase in the coupling area between the

Current pipes and in particular an associated increase in the current carrying capacity of the device can also be achieved in a favorable manner with increased sealing effect by the fastening nut forming a stepped nut which has a

-δ- 1

External thread projection in the manner of the external flange of the disc tube body. While the stepped nut, including a contact sleeve in connection with the external thread flange of the disc tube body, takes on the function of a first union nut, in this preferred embodiment of the innovation, a further union nut, including a further contact sleeve, which is supported on the external thread projection of the stepped nut for press engagement with the flow tube, is screwed onto the axially extending external thread projection of the stepped nut. In this way, a series connection of contact sleeves is created at least at the end of one flow tube, preferably on both flow tubes.

tact sleeves for power supply directly and by means of the j step nut on the disc tube body and via

j created this on the other power pipe.

Preferably both within the inner section

j 20 of the external thread flange of the disc tube body ' as well as within the external thread projection of the

An O-ring is provided for each stepped nut so that j the sealing capacity of the device is also increased.

- is improved. It depends on the input

Set conditions advantageous to provide such a series arrangement consisting of a step nut and a union nut including a contact sleeve each on both sides of the disc tube body at each end of the flow tubes to be connected to each other 3Q.

Advantageously, the contact sleeve has a radially projecting, reinforced collar section via which a propelling axial force is applied to the contact sleeve by the union nut or the

btufenmutter, and this collar section is followed by a cylindrical section tapering in the axial direction , which preferably gives the contact sleeve a barrel-shaped inner contour to increase the surface pressure between the contact sleeve and the circumferential surface of the current tube. The material used for the contact sleeves is preferably a hard copper alloy that is silver-plated.
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In order to convert the axial sliding movement of the contact sleeve when screwing the union nut or stepped nut onto the external thread flange of the disc tube body or the external thread projection of the stepped nut into a radial clamping movement of the cylinder section of the contact sleeve, the latter preferably has a conical circumferential section at its end opposite the collar section for sliding onto a corresponding inner counter surface of the external thread flange or the external thread projection. The contact sleeve is thus effective both as a current transmission element and as a clamping fastening wedge between the associated end section of the current tube and the external thread flange of the disc tube body or the external thread projection of the stepped nut.

A further preferred embodiment of the innovation, which also makes it possible to compensate for variations in the diameter of the power pipes to be connected within the device for coupling them without loss of coupling strength, power transmission capacity and sealing, consists in the contact sleeve being elastic in the area of its cylinder section.

This can preferably be achieved by removing the contact sleeve from its side opposite the collar

The contact fingers are slotted like collets at the end above to form contact fingers, so that the contact fingers always come into firm clamping engagement with the respective end section of the current tube by corresponding axial displacement of the contact sleeve and sliding of the contact fingers on the wedge surfaces of the external thread flange or external thread projection. Improved contact with increased surface pressure can be achieved by having the areas of the contact fingers that come into contact with the current tube designed like sawtooths.

In particular, in the case where a flow tube is at least partially designed as a flexible hose, in an advantageous embodiment of the innovation, the disc tube body, which is only provided with an external thread flange on one side, can be connected on its opposite side to the front end of the flow tube in a materially bonded manner, e.g. soldered, while the coupling to the other flow tube is made via the external thread flange of the disc tube body by means of a screw connection using at least one contact sleeve in the prescribed manner.

If position tolerances between the flow pipes to be connected to one another are to be compensated or if the connection of two flow pipes is intended which, due to their operation, move relative to one another, a flexible connection of the flow pipes is provided in an advantageous further development of the device according to the innovation in that a flexible, conductive hose is connected at each end to a disk body, preferably in a material-locking manner.

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and the disc bodies are each connected to the j end section of a rigid flow tube using

I Turning the external thread section of the disc

pipe body with the help of the on the power pipe-5
f liehen union or step nut including

i is coupled to at least one contact sleeve.

,Preferably, in the context of a flexible connection of the flow pipes, the disc pipe body forms a cable head and is provided on its side opposite the external thread flange with a hollow cylinder section which has recesses for receiving the ends

a plurality of 15 copper cables arranged coaxially to the cable head, which are soldered or pressed into the cable head.

I Furthermore, the hollow cylinder section preferably has

f a central hole for receiving the end

I 20 a spiral that is outside the cable head of

S surrounded by a perforated, first cable protection tube

F, which is surrounded concentrically by the copper cables.

ii outside, the copper cables are preferably connected by a

■· Rubber hose wrapped, which is secured by means of hose clamps

■ 25 ^on the outer circumference of the hollow cylinder section of each cable head.

^ The innovation is explained below using implementation

I examples and associated drawings in more detail

I 30 purified. In these show:

i Fig. 1 a coupling device for connecting

the end sections of two coolant-carrying flow pipes in longitudinal section, after a

first example of the innovation, 35

Fig. 2 shows another embodiment of a coupling device for connecting power pipes in half-cut,

Fig. 3 a coupling device according to Fig. 2 with modified contact sleeves,

Fig. 4 a contact sleeve in partial cross-section according to Fig. 5,

Fig. 5 shows a peripheral section of a contact sleeve according to Fig. 3,

Fig. 6 shows a half section of a device for the flexible coupling of flow pipes in the area of one of the flow pipes to be connected.

Fig.1 shows a device for coupling current pipes 1, such as those used for example to supply power to the electrodes of arc melting furnaces and through which a cooling liquid flows due to the high current heat load. The basic element of the device is a disc tube body 2 which, provided with a central opening, is arranged between the front sides of the end sections 5 of the current pipes 1 and which optionally has a hexagonal surface on its outer circumference for engagement with a wrench. The disc tube body 2 has an axially projecting, integral external thread flange 3 on both sides for receiving the respective end section 5 of the current pipes 1 in a section 4 of the external thread flange 3.

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These inner sections 4 each have a conical inner surface 8 which surrounds the front end area of each flow tube 1 in the coupled state. In this way, between the discs A wedge-shaped annular gap is formed between the end sections 5 of the flow tubes 1 received in the pipe body 2 and the inner surfaces 8 of the external thread flanges 3.

On each end section 5 of the flow tubes 1 there is an axially movable

union nut 6, into which also f

a contact sleeve 7 made of highly conductive material, e.g. a ver- i<

silver-plated hard copper alloy. Each cap I

&Lgr; 5 nut 6 has an internal thread section as a counter thread to 1

the respective external thread of the external thread flanges 3, so that |

the union nuts 6 in Fig. 1 from the left or from |

on the right on the corresponding external thread flange |

3 of the disc tube body 2 can be screwed on,

The contact sleeves 7 preferably have a \

greater hardness than the end sections 5 of the current- '-■

tubes 1 and each have a barrel-shaped 1

Inner contour, so that each contact sleeve 6 in the area |

a rear waistband section 10 and a front, ^}

inner ring edge 13 rests against the outer surface of the flow tube 1.

In addition to the rear collar section, which is supported in the base area of the union nut 6 and projects radially 10 of the contact sleeve 6, this has a cylinder section 9 extending axially from the collar section 10, which has an outer conical circumferential section 11. The angle of inclination of the conical circumferential section 11 of each contact sleeve

3g 7 corresponds to the angle of inclination of the corresponding conical inner surface 8 of the respective

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External thread flange 3, so that when the contact sleeve 7 is axially advanced by the union nut 6 into the space between the end section 5 of the

flow tube 1 and the external thread flange 3 of the

The conical inner surface 8 acts as an inclined plane along which the conical peripheral section 11 of the associated contact sleeve 7 slides in the wedge-shaped annular gap formed by the disc tube body 2.

When producing a coupling connection of the flow pipes 1, after inserting them into the inner sections 4 of the disc tube body 2, the corresponding over- union nut 6 is screwed onto the corresponding external thread flange 3 with a specified torque, whereby the contact sleeves 7 are pushed into the wedge-shaped annular gap between the flow tube 1 and the external thread flange 3 and the conical Inner surface 8 of each external thread flange 3 leads to a radial force component on the front end section of each contact sleeve 7, with the result that the front inner ring edges 13 of the contact sleeves 7 are inserted into the lateral surfaces of the end sections 5 of the current tubes 1, with the result that on the one hand, due to high contact pressure, a contact is made for conducting the electric current from a current tube 1 via the contact sleeve 7 to the disc tube body 2 made of conductive material. the other flow tube 1 with very low transition resistance and that at the same time a satisfactory sealing of the end section 5 of the flow tube 1 adjacent to the disc tube body 2 against the leakage of cooling liquid is achieved.

OC is sufficient. The special tightness of the device also results from the fact that each flow pipe end

next axially tightly against the middle part of the disc tube body 2, whereby its central opening for guiding the cooling liquid corresponds to the inner diameter of each flow tube and the contact sleeves 7 then serve to seal the narrow, wedge-shaped annular gap between the respective flow tube

1 and the external thread flange 3 of the disc tube body 2. After the cooling liquid has already in the event of its leakage, a deflection of

2 x 90° or 180° in order to even get into the annular space between the end section 5 of the flow pipe 1 and the associated external thread flange 3, the press fit of the contact sleeve between the flow tube 1 and the disc tube body 2 ensures a final seal that fully meets practical requirements. If necessary, an additional sealing ring can also be provided in this area, as explained in detail using the exemplary embodiments in Fig. 2 and 6.

In the manner described above, a coupling of two flow pipes can be achieved that can be released at any time and is easy to assemble, with only low contact resistance occurring within the coupling device and at the same time having a high degree of tightness with regard to the guidance of the cooling liquid in the flow pipes and through the coupling device.

Fig. 2 shows a half-section of another embodiment of a device for coupling flow pipes carrying coolant, which leads to an increased current carrying capacity as well as to a high coupling strength and tightness of the flow pipe coupling against the leakage of coolant.

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1 The coupling device according to Fig. 2 distinguishes

differs, among other things, from the coupling device according to Fig. 1 in that at one end section ₅ of the current pipe 1 a series arrangement of a pair of contact \ sleeves 18 and a modified

design of the contact sleeves 18, the consideration

certain diameter fluctuations in the outer diameter of the end sections 5 of the flow tubes 1. The j disc tube body 2 has a structure as

already in connection with the disc tube body 2 according to Fig. 1. In the present embodiment, however, the union nut 6 has been replaced by a stepped nut 16, which has an external thread projection 17 extending axially in the direction of the flow pipe 1 to be coupled,

\ whose design essentially follows the design of the

j External thread flange 3 of the disc tube body 2

! and which has an external thread of the same

nominal dimensions. This external thread 20 ,

projection 17 of the stepped nut 16 serves as a counter bearing*

for a further contact sleeve 13 arranged behind the first contact sleeve and as a receptacle for the screwable onto the external thread projection 17

union nut 6 , which is used to hold the second Kon-25

clock sleeve 18 is provided.

To compensate for diameter fluctuations and to ensure a high contact pressure of the contact sleeves regardless of an undersize with regard to

30

<res outside diameter of the end sections 5 of the flow tubes 1, the contact sleeves 18 are in the present case elastically designed in the area of their cylinder section 9, in that they are collet-shaped from their end opposite the collar section.

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are slotted so that a plurality of

Contact fingers 12, which lead to a certain variability in the diameter of the contact sleeve 18 in the area of its clamping or pressing connection with the associated end section 5 of the current tube 1. To further improve the electrical contact or to reduce the contact resistance, the contact fingers 12 are provided with a sawtooth contour 14 on their edges facing the current tube 1, so that with an enlarged contact surface a reduction in the contact pressure is avoided and the contact fingers 12 are pressed into the surface of the end sections 5 of the current tubes 1.

In this case, an improved tightness of the coupling device is achieved by the fact that within the wedge-shaped annular gap, which is provided between the external thread flange 3 of the disc tube body 2 or the external thread projection 17 of the stepped nut 16 and the end section 5 of the flow tube 1 for clamping the contact fingers 12 of the contact sleeves 18, an O-ring is arranged on the inside with respect to the contact fingers 12, so that the radial seal between the flow tube 1 and the disc tube body 2 or the stepped nut 16 is further improved. In this embodiment, the external thread flange 3 or the similarly shaped external thread projection 17 of the stepped nut

3Q 16 as an inclined clamping fastening plane serving to generate a radial force, whereby, due to the elastic design of the contact sleeves 18, the tightening force of the stepped or union nut 16,6 becomes effective directly as pressing forces between the contact fingers 12 of the contact sleeves 18 and the end section 5 of the current tube 1. Of course

&bull; Ml ·�Mgr; . .- ta · -. * ■* ·

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Here too, all elements of the device, in particular the stepped nut 16, are made of a material that is highly electrically conductive. The coupling device is preferably designed symmetrically and the other end of the current pipe (not shown here) to be coupled to the current pipe 1 shown is also coupled via the disc pipe body 2 using a screw combination consisting of a stepped nut and a union nut, including two contact sleeves.

This device for coupling the flow tubes 1 is also easy to assemble or disassemble, ensures a very good current connection via the disk tube body 2 via the sawtooth-shaped contact fingers 12 and, taking into account tolerances with regard to the external diameter of the flow tubes, leads to a coupling design in which additional combinations of radial sealing rings 15 reliably exclude any leakage of coolant from the flow tubes 1 in the coupling area. The contact sleeves 7 and 18 are effective both as essential current transmission elements and as clamp fastening elements and as sealing elements, regardless of the fact that the pipe disk body itself also takes over the frontal current conduction from one current pipe 1 to the other current pipe 1, and make it possible to create a coupling device for connecting current pipes, in particular high-current pipes, which is simply constructed and consists of a few individual parts, but is highly resilient and reliable and can be released at any time.

Fig. 3 shows a further modification of the coupling device according to Fig. 2, wherein in Fig. 3 the collar section 10 of the contact sleeves 18 has been slightly modified compared to the previous embodiments and has also been given a wedge surface design.

Figures ¹ J and 5 show a detail of such a contact sleeve 18 made of highly conductive hard copper material that is silver-plated, in an enlarged view. For example, the cylinder section of the contact sleeves 18 has twelve slots 19 so that each contact sleeve 12 has contact fingers 12 which are pressed into the surface of each current tube end 5 with their inner sawtooth contour 14. Fig. ¹ J shows

! a partial section through the contact sleeve 18 in the area

' of a slot 19. Additional slots 19 are not shown for the sake of simplicity. The wedge surface design in the area of the collar 10 of the contact sleeves 18 leads to the radial

^! forces to an even firmer overall fit of the contact

\ sleeves 18.

[ 25 ^{In the manner of} representation according to Fig. 2 with a single

« side screw connection and a disc tube body 2,

\ which is only fitted with an external thread flange on one side

;. 3 can be provided in a further embodiment

form of the innovation of the disc tube body on the other hand (left in Fig. 2) directly materially bonded, e.g.

by soldering to the other power tube 1. This can be particularly advantageous if, to compensate for positional tolerances, one of the

Flow pipes 1 are at least partially elastic in the manner of a flexible hose, or if a double-sided screw connection of the coupling device is to be dispensed with.

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In the event that the device is to be used to connect two current pipes whose position relative to one another changes, for example due to operation, as is necessary to compensate for the lifting movement of the electrodes of an arc furnace or if the transmission of mechanical vibrations from one current pipe 1 to the other current pipe 1 is to be avoided, the device can preferably be modified so that the disc tube body 2 according to Fig. 1 is separated in a radial center plane into two disc tube bodies 2, each with an external thread flange on one side (cf. illustration in Fig. 2) and each of these disc tube bodies is connected in a materially bonded manner, e.g. by soldering, to the end of a conductive connecting hose. In this way, the screw coupling of the flow pipes 1 shown in Fig. 1 and 2 can be retained with a part of the device for coupling the flow pipes 1 to the cable head, while at the same time an unhindered relative movement of the flow pipes 1 to each other is possible or the connection of flow pipes that are not axially aligned with each other can be carried out by the device with unhindered coolant flow and the end cable heads are connected to each other by a flexible, conductive hose connection.

An embodiment of such a flexible device for coupling the power pipes 1 is shown in half section in Fig. 6 for the connection area of a power pipe 1. The disc tube body 2 forming a cable head is provided with the external thread flange 3 on its screw fastening side facing the power pipe 1, as has already been explained in the previous embodiments. The

The coupling connection to the current pipe 1 is made by means of two contact sleeves 18 (the slots 19 of which are here for not shown for simplification) in the same way as was already explained above with reference to Figures 2 and 3. Opposite this, the disc tube body 2 is provided with a hollow cylinder section 20 which is used to hold a flexible

_ len cable connection to the cable head or disc tube body 2 (not shown here) at the other end of the cable connection or the flexible connecting hose.

The hollow cylinder section 20 has a central 5

enlarged mounting hole 21, in which the end of a metallic spiral 22. The spiral 22 provides the flexible hose connection of the cable heads or disc tube bodies 2 with sufficient flexibility and elasticity while at the same time providing mechanical stability. Outside the receiving bore, the spiral 22 is surrounded by a perforated cable protection hose 23 made of rubber. Cooling water for cooling the

Power tubes 1. In its front face, the

Hollow cylinder section 20 is provided with recesses 2k evenly distributed in the circumferential direction, wherein a hot-dip tinned copper round cable 25 is inserted into each of these recesses and connected to the hollow cylinder section 2Ö ^e V?erfSteifst. In this way, a

high current carrying capacity of the coupling device of the power pipes 1. Within the flexible hose connection, the openings of the perforated cable protection hose 23 lead to the contact of the cooling water with the copper cables 25 and contribute to a

more even current distribution across the cross section the hose connection at . To the outside, the

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The flexible device is sealed coolant-tight by a cable protection hose which is secured to the circumference of the hollow cylinder section 20 by hose clamps 27. On the side of the screw connection elements of the device, namely the stepped nut 16 and the union nut 6, the O-ring 15 contributes to sealing the device, as already explained in connection with the other embodiments.

The new device for coupling coolant-carrying flow pipes is thus characterized by a considerable variability of its application possibilities with low contact resistance, high current carrying capacity and tightness against coolant losses.

Claims (1)

-1- Protection claims
1. Device for coupling coolant-carrying flow pipes, characterized by a conductive disc tube body (2) with at least one essentially axially projecting external thread flange (3) which has an inner section (4) for accommodating an end section of the flow pipe (1), a fastening nut (6, 16) held on the flow pipe (1) and engageable with the external thread flange (3), and a fastening nut (6, 16) which is held by the loading 15 Axially displaceable contact sleeve (7, 18) which can be brought into press engagement with the end section (?) of the flow tube (1) by means of a fastening nut (6, 16) supported on the external thread flange (3). 2. Device according to claim 1, characterized in that the disc tube body (2) has an external thread flange (3) on opposite end faces for receiving an end section (5) of a flow tube (1), with each external thread flange (3) being assigned a union nut (6) and a contact sleeve (7). 3. Device according to claim 1 or 2, characterized in that the inner section (1) of the external thread flange (3) has a conical inner surface (8) for forming a wedge-shaped annular gap to the end section (5) of the flow tube (1), in which the contact sleeve (7, 18) can be partially received. 4. Device according to claim 1, characterized, that for the mutual sealing of flow pipe (1), Disc tube body (2) and contact sleeve (7, 18) inner &ogr; At least one O-ring (15) is accommodated within the inner portion (4) of the external thread flange (3). 5. Device according to claim 1, characterized in that the fastening nut is a stepped nut (16) with an external thread projection (17). 6. Device according to claim 5, characterized in that the external thread projection (17) of the stepped nut (16) corresponds in its geometry essentially to the external thread flange (3) of the disc tube body (2). 7. Device according to claim 5, characterized in that, including a further contact sleeve (18), a union nut (6) is placed on the stepped nut (16) for press engagement of the further contact sleeve 26 (18) can be screwed onto the end section (5) of the flow tube (1). 8. Device according to claim 5, characterized. that the diametrically opposed external thread flanges (3) of the disc tube body (2) are each assigned an end section (5) of a flow tube (1) and a stepped nut (16) with union nut (6) including the respective associated contact sleeves (18). -3- 9« Device according to claim 1 or 7, characterized in that the contact sleeve (7» 18) has a radially projecting, reinforced collar section (10) and a tapering cylinder section (9) extending axially therefrom. 10. Device according to claim 9, characterized in that the contact sleeve (7, 18) has at its end opposite the collar section (10) a conical peripheral section (11) for contact with the inner surface (8) of the external thread flange (3) or an inner counter surface of the external thread projection (17) of the stepped nut (16). 11. Device according to claim 9, characterized in that ^the contact sleeve (7, 18) has a barrel-shaped inner contour. 12. Device according to claim 9, characterized in that the contact sleeve (7, 18) has a greater hardness than the associated flow tube (1) and an inner ring end edge (13) of the contact sleeve (7, 18) can be brought into notched engagement with the flow tube (1). 1-3· Device according to claim 1, characterized in that the contact sleeves (7, 18) are made of a silver-plated material having a high hardness and high thermal and electrical Conductive copper alloy. 35 · * I 14. Device according to claim 9, characterized in that the contact sleeve (18) is elastic in the region of its cylinder section (9). 15. Device according to claim 14, characterized in that the cylinder section (9) of the contact sleeve (18) is slotted like a collet to form contact fingers (12) and the contact fingers (12) formed by slots (19) have a sawtooth contour (14) for engagement with the current tube (1). 16. Device according to claim 1, characterized in that the disc tube body (2) is provided on one side with the external thread flange (3) and is integrally connected on its opposite side to a front end of a flow tube (1). 17. Device according to claim 16, characterized in that the flow tube (1) is at least partially a flexible hose. Device according to claim 1, characterized in that a flexible, conductive hose is connected at each end to a disc tube body (2) and the disc tube bodies (2) are coupled to the end section (5) of a rigid flow tube (1) by means of the fastening nut (6, 16) located thereon, including the contact sleeve (7, 18). & P] ASeoK-.&khgr; -5- 19.Device according to claim 18, characterized in that the disc tube body (2) is provided on one side with the external thread flange (3) and is coupled to a stepped nut (16) of the associated flow tube (1) with the inclusion of a contact sleeve (18), and a union nut (6) located on the flow tube (1) is screwed to the stepped nut (16) with the inclusion of a further contact sleeve (18). 20. Device according to claim 19,
characterized in that the disc tube body (2) forms a cable head and on the other hand a hollow cylinder section (20) into which the ends of copper cables (25) are soldered. 21. Device according to claim 15 and 20, characterized in that the flexible, conductive hose consists of a central spiral (22) which is accommodated at the end in the hollow cylinder section (20), a perforated first cable protection hose (23) surrounding it the copper cables (25) and a 25 second cable protection hose (26), which is fixed by means of hose clamps (27) on the outer circumference of the hollow cylinder section (20) of the disc tube body (2). 22. Device according to claim 21, characterized in that the cable protection hoses (23, 26) are made of rubber.