DE2601107A1 - CORE AND CABLE SHEATH CONSTRUCTION WITH BETTER CORROSION RESISTANCE AND WATERPROOF, AS WELL AS METHOD OF MANUFACTURING THE SAME - Google Patents

Description

DR.STEPHAN G. BESZEDES PATENT ADVOCATE

806 DACHAU near MUNICH

BOX 1168

AM HEIDEWEG 2

TELEPHONE: DACHAU 4371 Postal checking account Munich (BLZ 700 100 80)

Account no. 1368 71

Bank account No. 90 637 at the district and city Sparkasse Dachau-Indersdorf (bank code 700 515 40)

P 880

B eschr eibu η g

for patent application

MAGYAR KABEL MÜVEK

Budapest, Hungary

concerning

Core or cable sheath structure with better Corrosion resistance and water tightness, and methods of making the same

The invention also relates to a neutral line and shielding usable wire or cable jacket construction with better corrosion resistance and Watertightness or water resistance and a method for producing the same.

As is well known, the metal jacket is an important cable component. The cable sheath has the task of sealing the cable core airtight and protecting it from external influences as well

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ORIGINAL INSPECTED

to protect against internal changes and also to close off the electrical field of the cable and the Conducting leakage currents on the surface of the cable core. The waterproof metal jacket can be made from lead or from Made of aluminum.

The process used in the manufacture of lead jackets for nearly a century is in the immediate Pressing on the jacket, but recently the lead jackets have also been applied by extrusion. The disadvantages of the lead jacket are that it is extremely expensive and a hazard in terms of lead disease and the soft metal coating offers very little mechanical protection. Lead jackets are generally used when using paper insulation, their use with plastic-insulated cores or respectively Cable, on the other hand, is rare. The lack of mechanical strength is mostly caused by one made of plastic or iron strips existing protective layer compensates.

Aluminum jackets can be produced by pressing on and also from elongated strips by welding or folding be applied. It can be welded warm, cold or with ultrasound. In any case, a protective layer is used Plastic sheath used.

The most common method of applying the aluminum jacket from elongated strips is cold welding. The aluminum jacket produced in this way is liquid and gas-tight. Starting material for the Production is a suitably wide rolled aluminum strip. When applying, the aluminum tape is next to the sheathed cable into the shaping or profiling row of rollers, which are made from the aluminum strip

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the aluminum jacket surrounding the cable is introduced. Afterward the log edges of the aluminum strip are made by cold pressing welded. In order to reduce the internal stresses caused by the strong cold deformation, a In the following work step, the entire aluminum jacket is quickly heated electrically and then immediately in one Cooled water bath and finally blow off the water, removed [Kabel Zsebkönyv, Volume I, 3 · improved edition, Magyar Kabelmüvek 1974 · »pages 235 to 24-2J. The disadvantage this method is that it is complicated and slow, as well as the cable as a result of the length of the The resulting multiple layer weld is stiff and difficult to bend. It is also disadvantageous that in this Only at least 1 mm thick tapes can be used, because thinner tapes can be welded do not perform under operating conditions.

For the sheathing of the aluminum sheet, polyvinyl chloride, less often polyethylene, polyethylene copolymers are generally used or a polyamide is used. These polymers are generally applied with an extruder. The one with However, the plastic jacket applied by the known method does not adhere to the metal jacket, but merely surrounds it tube-like, which is why watertightness is only available until the plastic jacket is damaged or water penetrates through diffusion between the metal jacket and the plastic jacket. Once water has penetrated then corrosion is inevitable.

According to British patent specification 1,272,482, both sides of the metal foil are covered in this manner with a plastic sleeve provided that the sides of the plastic tape applied in the longitudinal direction overlaps and by the action of heat are welded together. This plastic layer does not adhere firmly to the metal shell either, that is, it does not adhere to it either

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this way the corrosion of the metal shell, be it as a result an injury to the plastic cover or as a result penetrated by diffusion through the outer plastic shell Water, not to be prevented.

According to the Soviet patent specification 205 90 $ is used to join the overlapped sides of the in the longitudinal direction an adhesive is used on the plastic tape, which is dropped onto the surface to be glued. In this technical solution, too, there is between the metal jacket and the plastic cover no adhesion, so that no protection against corrosion is guaranteed.

In the case of power cables, the one provided with an aluminum sheath corresponds to that produced according to the known method Wire or cable sheath also does not meet the strict requirements regarding neutral line shielding and the mechanical protection are prescribed in the international standards.

The invention is based on the object of eliminating the disadvantages of the prior art, a shielding, prevent electric shocks and short circuits Cable sheath structure with better corrosion resistance and water tightness, also as a neutral line and shielding is usable and on high and low voltage cable cores or cables in a simple manner and with little effort while achieving cables with a higher load capacity than with the known ones Shell structures can be applied, as well as a method for producing the same to create.

The invention is based on the finding that this object can be completely achieved and at the same time the

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Use of much thinner aluminum sheets compared to the "previously used" is made possible if the Aluminum shell coated on both sides with a self-adhesive coating of special composition and the Aluminum shell with the help of this lacquer layer both with the inner graphite layer and with the outer plastic shell is connected practically seamlessly or without gaps.

The invention therefore relates to a wire or cable sheath structure with better corrosion resistance and watertightness, which can also be used as a neutral line and shield from a shielding or protecting against electric shock and short circuits preventive, tubular aluminum shell in the longitudinal direction made of at least one aluminum strip and a cohesive plastic casing applied to it, which is characterized in that the Aluminum envelope of one or more aluminum strips with a maximum thickness of 0.6 mm, preferably 0.1 to 0.5 m, which on both sides with one to 55 to 85 wt .-%, preferably 70 to 80 wt .-%, of polyvinylidene chloride and / or one or more copolymers of the same, to 10 to 35% by weight, preferably 12 to 16% by weight, of polyvinyl chloride and / or one or more copolymers thereof and to 3 to 20 wt .-%, preferably 5 to 8 wt .-%, . Made of polyvinyl acetate, polyvinyl propionate, polyvinyl butyrate and / or polyvinyl acrylate and / or one or more copolymers of the same existing lacquer layer are coated with a Overlap of 0.1 d to 1 d, preferably 0.4 d to 0.6 d (d »inner diameter of the jacket), is formed.

The invention also provides a method for

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Production of the wire according to the invention

which is characterized in that on the Insulation layer of the wire or of the cable from the one or more coated with the lacquer layer Aluminum strips by applying them in the longitudinal direction, the tubular aluminum shell with the as specified above Overlap formed and applied to the plastic cover will.

The self-adhesive varnish used in the present invention is generally liquid at room temperature. It can therefore be used both undiluted and in the form of a solvent prepared solution or dispersion can be applied. It can be applied in one layer or in several layers Aluminum tape or the aluminum foil are applied. The application can be by dipping, spraying or Can be deleted. The lacquer layer can also be achieved by sintering the lacquer powder onto the surface of the aluminum strip or the aluminum foil are formed.

The lacquer layer applied in the manner described forms in the solidified state on both sides of the Aluminum is a cohesive layer. Markings can be placed on the surface of the treated aluminum strip Color markings or letters can be attached.

Pure the sheathing of the aluminum-sheathed wires or cables can be any plastic previously used for such purposes, primarily polyvinyl chloride will.

The main advantages of the wire or cable sheath structure according to the invention and method for its production are as follows:

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a) The shell structure "provides for the aluminum shell complete corrosion protection, because over the entire contact surface of the Aluminum tape or the aluminum foil and the plastic cover a good adhesion consists. Therefore, no corrosion occurs on the surface of the aluminum shell even if if the plastic shell has cracks or other Injuries or if water diffuses through the plastic cover.

b) Due to the flawless corrosion protection of the The jacket structure according to the invention can be used with the aluminum strip or the aluminum foil not only for low-voltage cables and communication cables, but also for Power cables are used. This makes it possible to protect against electric shocks Using aluminum instead of more expensive materials like copper.

c) The mechanical strength of the jacket structure according to the invention is just as high as that of the shell structures formed by welding.

d) According to the invention, extremely thin, only a few microns thick aluminum foils can also be used be processed, which means on the one hand a material saving and on the other hand the achievement more flexible cable allows.

e) The thin aluminum casings which can be used according to the invention can be colored and coated with the

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each desired text containing the manufacturing data of the cable can be provided.

f) With the inventive method, the aluminum shell can be much faster than "previously be applied.

g) The inventive method is for waterproof and corrosion-resistant training equally suitable for single-core and multi-core cables.

The invention is illustrated by the following non-limiting examples in connection with the explained in more detail in the accompanying drawings.

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example 1

Manufacture of a power cable with a cross-section of 7 ( Voltage of 20 kV

ρ a core cross-section of 70 mm for a

On the wires of a twisted line 1 of the cable shown in Figure 1 were successively in a conventional Way a semiconducting layer 2 formed from polyethylene with an addition of active carbon black, then a core insulation 3 made of polyethylene and finally a graphite coating 4 · applied to this.

After applying the graphite coating 4- the Cable with an aluminum sheath 5, which was made of a 0.20 mm thick and 50 mm wide aluminum tape, provided. The strips of this width were made from a 400 mm long, 800 mm wide and 0.2 mm thick aluminum sheet cut out, both sides of which had previously been coated with a layer of varnish of the following composition:

70 wt% polyvinylidene chloride 22 wt% polyvinyl chloride 8% by weight polyvinyl acetate

The application of the paint coating was carried out in a liquid to 50 to 60 ⁰ C heated coating bath of the above Zusammei reduction, by which the sheets were pulled.

The coming out of the bath sheet was passed through an existing at 120 to 130 ⁰ C HEATER ^ eight roll pairs Walzenroi hey, wherein the pressure applied to the aluminum sheet ·. 3 fuel coating cured. In this way became a

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8 to 10 Ai thick lacquer formed.

The 50 mm wide strips were cut out of the aluminum sheet provided with a plastic coating on both sides and applied to the cable in the longitudinal direction at a speed of 12 to 16 m / minute. By this device serving the aluminum band during the molding was heated to tube at 150 bi ^ 16O ⁰ C and pressed after the formation of the tube with an appropriate caliber to the coated graphite cord. A permanent bond was created between the graphite layer and the lacquer layer covering the surface of the aluminum strip. Simultaneously, the L _a fused ckschichten to the overlapped portions of the aluminum strip due to the effect of heat with each other, was waterproof whereby the aluminum sheath. 5 The aluminum tape 5 was overlapped in a width of 6 mm.

The cable provided with the aluminum tape 5 was extruded in an extruder with a 2 to J mm. thick polyvinyl chloride jacket 6 provided. An air-free adhesion was created between the outer polyvinyl chloride jacket 6 and the outer lacquer layer of the aluminum sheath 5, through which the cable was completely watertight even if the outer polyvinyl chloride jacket 6 was damaged.

The covered cable was wound on a drum after cooling with water.

The cable made in this way could be 18 to 20% higher are loaded than an otherwise completely identical cable made with an unpainted aluminum strip.

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Example 2

Manufacture of a power cable with a cross-section of 3 χ 120 β a voltage of 20 kV

ρ a core cross-section of 3 χ 120 mm for

To manufacture the three-core cable shown in FIG. 2, the three cores were first made: On each aluminum full loader 1 of circular cross-section was first one made of polyethylene in a conventional manner existing core insulation 3 applied, which had a graphite coating on its surface. After that there was a first Aluminum shell part 5 in that described in Example 1 Formed from a 0.20 'mm thick and 80 mm wide aluminum strip 5, which is sprayed on on both sides with an 8 to 10 foot thick lacquer layer of the following composition had been coated:

80% by weight polyvinylidene chloride 15% by weight polyvinyl chloride ■ 5 wt% polyvinyl butyrate

The cores 1 encased in aluminum were arranged symmetrically around an earth or neutral line 7 made of aluminum, whereupon three space-filling molded bodies or profiles 8 made of polyvinyl chloride were attached outside along the contact line of the three cores 1

became. The composite obtained in this way was then applied with a thickness of 12 mm Overlap a 150 mm wide and 0.2 mm coated on both sides with a layer of lacquer of the above composition thick aluminum tape 5 'applied, the aluminum tape 5' along the overlap a closed by the action of heat. Tube made.

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2601Ί

After that, with the help of an extruder, an external one was made Polyvinyl chloride jacket 6 applied to the cable. The outer polyvinyl chloride jacket 6 was firmly adhered to the outer one Lacquer layer of the aluminum tape 5 'and thus formed one waterproof and corrosion-resistant cover.

Example 3

Manufacture of a power cable with a cross-section of 3 x 70 a voltage of 1 kV

ρ a core cross-section of 3 x 70 mm for

The cores 1 of the cable shown in FIG. 3, consisting of solid sectors made of aluminum, were provided with an extrusion device with a core insulation 3 made of polyvinyl chloride and at the same time with a color code. Three of these wires 1 were put together in the manner shown in FIG. 3, between the wires 1 the ground or neutral line 7 made of aluminum, divided into three parts, was inserted between the wires 1 and then the cable was twisted. A 110 mm wide and 0.2 mm thick aluminum sheath 5, which was provided on both sides with a lacquer layer of the following composition, was then applied to the now round cable in the manner described in Example 1:

55% by weight polyvinylidene chloride, 30% by weight polyvinyl chloride 15% by weight polyvinyl acrylate

The layers of lacquer on the sides of the aluminum strip that were overlapped by 8 mm were bonded to one another by the action of heat

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merged. This created a from the aluminum strip closed tube. On the one provided with the aluminum shell 5 Cable, a polyvinyl chloride jacket 6 was then applied with an extruder, which was attached to the outer layer of lacquer the aluminum shell 5 was firmly adhered. The cable, which was wound onto a drum after cooling, was completely waterproof and corrosion resistant.

Claims

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Claims (2)

- 14 - Claims Core or cable sheath structure with better corrosion resistance and watertightness, which can also be used as filler line and shielding, consisting of an aluminum sheath, which is tubular in the longitudinal direction and is tubular in the longitudinal direction and made of at least one aluminum strip and a coherent plastic sheath applied to it, which shields or protects against electrical shocks and prevents short circuits, characterized in that the aluminum shell (5; 5 »5 ¹ ) of one or more at most 0.6 mm, preferably 0.1 to 0.5 eu &> thick aluminum strips (5> 5 ')» which on both sides with a to 55 to 85% by weight, preferably 70 to 80% by weight, of polyvinylidene chloride and / or one or more copolymers thereof, to 10 to 35% by weight, preferably 12 to 16% by weight, of polyvinyl chloride and / or one or more copolymers of the same and up to 20% by weight, preferably 5 to 8% by weight, of polyvinyl acetate, polyvinyl propionate, polyvinyl butyrate and / or he polyvinyl acrylate and / or one or more copolymers of the same existing lacquer layer are coated with an overlap of 0.1 d to 1 d, preferably 0.4 d to 0.6 d (d = inside diameter of the jacket). 2.) Process for making the Ada> Reference lens structure according to Claim 1, characterized in that one or more with the lacquer layer on the insulation layer of the core or the cable coated aluminum strips through their - 15 609829/0681 2BU! "IU / - 15- Applying in the longitudinal direction the tubular Aluminum shell with the as defined in claim 1 Forms an overlap and applies the plastic cover to it. BO9829 / 068 1 Jb Blank page