A photoelectric hybrid cable and a method for preparing the same

Abstract

The present invention discloses a photoelectric hybrid cable and a preparation method thereof, which belongs to the field of cable preparation. The present invention comprises a vertically symmetrical rectangular insulated wire and a horizontally symmetrical butterfly optical cable, wherein the rectangular insulated wire is positioned by a positioning support element and the butterfly optical cable is supported, the rectangular insulated wire is composed of three strands of twisted copper wire and flame-retardant polyvinyl chloride insulation material, and the butterfly optical cable is composed of an optical fiber, a copper-plated steel wire and a flame-retardant sheath, and a steel wire bonding layer is extruded on the surface of the copper-plated steel wire; the cable core is wound with a fire-resistant cloth tape, and a flame-retardant polyvinyl chloride sheath is extruded outside the fire-resistant cloth tape. The product of the present invention reduces the outer diameter of the product, reduces the cost, and takes into account flame retardancy, environmental protection and synchronous transmission of optical and electrical signals, and is suitable for the deployment of various types of 5G base stations.

Description

Technical Field

[0001] The invention belongs to the field of cable preparation, in particular to a photoelectric hybrid cable and a preparation method thereof. Background Art

[0002] With the intensive deployment of 5G networks in recent years, a large number of outdoor communication base stations, mobile base stations, and communication terminal equipment have been laid, and the requirements for laying optical cables have gradually increased. Convenience, environmental protection, high cost performance and fast transmission have become new requirements for cables.

[0003] Optical-electric hybrid cables can transmit optical signals and provide power supply at the same time, which greatly reduces the laying and operation costs. However, with the gradual increase in usage, users have put forward higher requirements on prices, and designing a stable structure and a smaller outer diameter has become an urgent requirement. Therefore, more and more special-shaped optical-electric hybrid cables have appeared in front of everyone. Although the special-shaped structure helps to reduce the outer diameter of the product and reduce costs, the structural stability and performance guarantee of each component have always been the hidden dangers of such cables. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention discloses an optoelectronic hybrid cable. The optoelectronic hybrid cable of the present invention comprises vertically symmetrically arranged rectangular insulated wires and horizontally symmetrically arranged butterfly optical cables. The optoelectronic hybrid cable of the present invention reduces the outer diameter of the product and reduces the cost, while taking into account flame retardancy, environmental protection and synchronous transmission of optical and electrical signals, and is suitable for the deployment of various types of 5G base stations.

[0005] The present invention is achieved in that:

[0006] A photoelectric hybrid cable, characterized in that the center of the photoelectric hybrid cable includes a rectangular insulating wire symmetrically arranged in an upper and lower direction, and butterfly optical cables are symmetrically arranged on the left and right sides of the rectangular insulating wire; the present invention replaces the circular insulating wire structure with a rectangular insulating wire structure, reduces the gap between the structures and the size of the insulating wire, thereby reducing the outer diameter of the photoelectric hybrid cable.

[0007] The rectangular insulated wire is positioned by a positioning support element, and the positioning support element supports the butterfly optical cable; the rectangular insulated wire includes three strands of special-shaped twisted copper wires and a first flame-retardant polyvinyl chloride insulation layer coated on the outside of the special-shaped twisted copper wires; the butterfly optical cable includes an optical fiber and a copper-plated steel wire symmetrically arranged above and below the optical fiber, and a steel wire bonding layer is extruded on the surface of the copper-plated steel wire; the optical fiber and the copper-plated steel wire are extruded with a flame-retardant sheath; the side of the flame-retardant sheath that is tightly pressed against the positioning support element has no stripping opening, and the side of the flame-retardant sheath that is away from the positioning support element has a stripping opening; the butterfly optical cable of the present invention extrudes and processes the copper-plated steel wire during production, so that a steel wire bonding layer is formed between the steel wire and the sheath material: after the sheath is stripped, the surface of the steel wire needs to be smooth and free of bonding layer residue. The steel wire used in the butterfly optical cable of the present invention is copper-plated, which improves the smoothness of the steel wire surface and simultaneously solves the hidden danger of mold blockage caused by extrusion.

[0008] Furthermore, the rectangular insulated wire and the butterfly-shaped optical cable form a cross-symmetrical structure, and four flame-retardant filling ropes are arranged at the four corners of the cross-symmetrical structure. Placing the four flame-retardant filling ropes at the four corners further enhances the product's lateral pressure resistance and impact resistance while ensuring the roundness of the cable core.

[0009] Furthermore, the stripping opening angle of the butterfly optical cable is reduced to 45°, and the depth is simultaneously reduced to 1.5 mm.

[0010] Furthermore, the rectangular insulated wire and the butterfly optical cable are wrapped with a layer of fire-resistant tape; a second flame-retardant polyvinyl chloride insulation layer is extruded outside the fire-resistant tape; the thickness of the fire-resistant tape is 0.4 mm. The fire-resistant tape fixes the cable core structure, resists fire, reduces shrinkage in high and low temperature cycles, and improves temperature resistance.

[0011] Furthermore, the three strands of special-shaped twisted copper wires arranged in the rectangular insulated wire are elliptical twisted copper wires.

[0012] Furthermore, the positioning support element is higher than the center of the rectangular insulated wire, and the positioning support element is higher than the butterfly optical cable, which solves the problem of insufficient pressure resistance on one side of the butterfly optical cable. The butterfly optical cable needs to be close to the positioning support element.

[0013] The present invention also discloses a method for preparing a photoelectric hybrid cable, which is characterized by comprising the following steps:

[0014] Step 1. Preparation of rectangular insulated wire: The three strands of special-shaped twisted copper wire of the rectangular insulated wire are regular rectangles. Three strands of special-shaped twisted copper wire are selected. The copper wires are actively paid out and placed in parallel. The diameter of the guide wheel must be greater than 100 times the diameter of the copper wire. They are all in a straight line from the pay-out end to the die core of the machine head, which can avoid deformation of the single copper wire under force. The three strands of copper wire are gathered together by the three magnetic eyes of the converging die, and are rolled and shaped by a double-pressure device regulated by a precision air pressure valve; limit devices are installed at the inlet and outlet of the double-pressure device, and an automatic calibration function is added; the automatic calibration function ensures that the inlet, outlet and crimping are always in a straight line, and the outlet is infinitely close to the extrusion die core, completely eliminating the hidden dangers of broken wires and mold blockage.

[0015] At the same time, the mold core is further shaped by selecting a rectangular structure, and the mold sleeve protrudes 0.1mm on the long axis to perform arc processing, which solves the problem of pressure collapse after extrusion and ensures that the insulated wire after molding is a rectangular structure

[0016] Step 2, preparation of butterfly optical cable: copper-plated steel wires are released in parallel, using an active pay-off device, and then straightened to avoid mold blocking and debonding caused by microbending. After straightening, they are preheated at 80°C to improve the bonding strength between the steel wire bonding layer and the copper-plated steel wire. After extrusion, the steel wire enters a cooling device for the steel wire bonding layer synchronously with the optical fiber. This device contains an optical fiber channel with a temperature of 80°C for optical fiber preheating; the channel is filled with convection argon gas to automatically transmit the optical fiber and reduce optical fiber oxidation; the outer side of the optical fiber channel is a cooling area for the steel wire bonding layer, and the temperature in this area is 80°C, increasing this area domain, to ensure that the bonding layer and the steel wire are fully bonded; then it enters the second-stage cooling device for the steel wire bonding layer, which contains an optical fiber channel. The temperature inside the optical fiber channel is 80°C, which is used for preheating the optical fiber; the optical fiber channel is filled with convection argon gas, which is used to automatically transmit the optical fiber and reduce optical fiber oxidation; the outer side of the optical fiber channel is the cooling area for the steel wire bonding layer, which is filled with 30°C compressed air, which is used to rapidly cool the steel wire bonding layer to avoid the liquid bonding layer clogging the mold core; at the same time, the surface temperature of the steel wire bonding layer is maintained at above 30°C, which improves the bonding strength between the steel wire bonding layer and the sheath material and ensures that the steel wire extraction force is above 100N. Then the butterfly optical cable is extruded;

[0017] Step 3. In the extrusion of the steel wire bonding layer, glue G103, inner skin material XK1059 and EAA in a mass ratio of 1:2.5:3 need to be uniformly stirred in a mixer for 10 minutes at a temperature of 50°C to ensure that the extruded steel wire bonding layer is compatible with the flame retardant sheath, and the surface of the steel wire is smooth and free of residue after peeling off the flame retardant sheath.

[0018] Step 4: Extrusion of copper-plated steel wire and optical fiber: a flame-retardant sheath is extruded on the optical fiber and copper-plated steel wire through a die, and the head temperature is 150°C, 160°C, and 165°C; in order to improve the bonding strength between the steel wire bonding layer and the flame-retardant sheath, a 1-meter preheating device is added between the head and the water tank, and the preheating temperature is 100°C;

[0019] Step 5. An active pay-off device is set in the cabling machine to place the positioning support element. A positioning device is installed at the double-wheel exit to prevent the positioning support element from twisting. The two butterfly optical cables and two rectangular insulated wires in the optoelectronic hybrid cable are paid out by a twisting cage. The pay-off frame and the twisting table are at the same angle, and no corners are allowed to appear, which avoids the twisting of the butterfly optical cable. A correction positioning mold is installed in front of the twisting table. The positioning mold is designed in a rectangular shape according to the size of the butterfly optical cable and the insulated wire. The rectangular insulated wire, butterfly optical cable and positioning support element enter the twisting mold after passing through the positioning mold. The twisting mold is designed separately. The design is divided into two sections. The first section is used to twist the rectangular insulated wire and the positioning support element. The positioning holes designed according to the size of the rectangular insulated wire solve the hidden danger of the insulated wire dislocation. When the rectangular insulated wire is located in the positioning support element, the cabling machine presses a pressure plate on the upper and lower parts of the rectangular insulated wire through a pneumatic device to position the rectangular insulated wire. After the pressure plate is in place, it enters the second section of the twisting die. The positioning holes are designed according to the size of the butterfly cable to solve the hidden dangers of butterfly optical cable dislocation and flipping. After the butterfly optical cable is in place, the flame-retardant filling rope is filled in the empty spaces on the four sides of the cable core, and then it is immediately wrapped and then coiled.

[0020] Step 6: After the cable core is completed, the sheath is extruded, that is, a layer of fire-resistant tape and a second flame-retardant polyvinyl chloride insulation layer are extruded in sequence, and then cooled and wound. Before entering the die head for extrusion, it first passes through the talcum powder device to ensure the extraction force between the sheaths, and then extrusion is gradually carried out.

[0021] Furthermore, the lower roller of the double-pressing device in step 1 is provided with a groove, the chamfers on both sides are smoothly transitioned, and the upper part is provided with a convex protrusion that fits perfectly with the groove. The crimping accuracy of the precision air pressure valve is 0.01mm. This ensures that the force on the single copper wire is within a controllable range during shaping.

[0022] Furthermore, the straightener described in step 2 uses 24 groups of straightening wheels placed crosswise, and the diameter of the straightening wheel is not greater than 5 times the diameter of the steel wire.

[0023] The beneficial effects of the present invention and the prior art are:

[0024] The butterfly optical cable of the present invention adopts copper-plated steel wire, that is, the steel wire is copper-plated, and a steel wire bonding layer is adhered between the steel wire and the butterfly optical cable sheath material, thereby improving the peeling force of the two. The rectangular twisted copper wire is replaced by three-strand elliptical twisted copper wire, thereby solving the problem that the twisted copper wire is squeezed and deformed, resulting in a reduction in the elongation at break of a single strand.

[0025] The present invention places two rectangular insulated wires vertically in the middle of the optoelectronic hybrid cable. A positioning support element is provided between the rectangular insulated wires to fix the position. The positioning support element needs to be higher than the center position of the rectangular insulated wires to ensure the positioning effect, thereby solving a series of problems such as tipping, misalignment and structural instability of the special-shaped insulated wires. The butterfly optical cable of the present invention is provided with a stripping opening on one side, which can solve the influence of stress concentration on the optical fiber while ensuring tearing.

[0026] In the method disclosed in the present invention: three strands of elliptical twisted copper wires are laid out in parallel, and enter the groove of the copper stranded wire forming mold through a convergence mold, and after forming, enter the rectangular mold core in the machine head for re-forming, and then extrude into a rectangular insulated wire through extrusion of flame-retardant polyvinyl chloride insulation material; the optical fiber and two steel wires are actively released, the surface of the steel wire is copper-plated to ensure the smoothness, and the bonding layer is extruded after straightening. After extrusion, it passes through a curing process and is extruded synchronously with the optical fiber to complete the butterfly cable extrusion; in the cable twisting, a full-process no-bending process is adopted, and the positioning support element and the rectangular insulated wire are twisted synchronously, and the process is assisted by a positioning device, which shortens the distance between the twisting of the butterfly optical cable and the fire-resistant cloth tape, and in the process of synchronous twisting, the positioning of each component is guaranteed, and the flame-retardant polyvinyl chloride sheath is extruded and formed after twisting; the product of the present invention reduces the outer diameter of the product, reduces the cost, and takes into account flame retardancy, environmental protection and synchronous transmission of optical and electrical signals, and is suitable for the deployment of various 5G base stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic structural diagram of an optoelectronic hybrid cable of the present invention;

[0028] Among them, 1-flame retardant filling rope, 2-steel wire bonding layer, 3-copper-plated steel wire, 4-optical fiber, 5-flame retardant sheath, 6-positioning support element, 7-special-shaped twisted copper wire, 8-first flame retardant polyvinyl chloride insulation layer, 9-fire-resistant cloth bag belt, 10-second flame retardant polyvinyl chloride insulation layer. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail by enumerating examples below. It should be noted that the specific implementation described here is only used to explain the present invention and is not used to limit the present invention.

[0030] The process of preparing a photoelectric hybrid cable of the present invention is as follows:

[0031] 1) In the production of rectangular insulated wires, in order to ensure the rectangular structure and minimum wall thickness, the copper wire needs to be a regular rectangle. Three elliptical twisted copper wires are selected. The copper wires are actively paid off and placed in parallel. The diameter of the guide wheel needs to be greater than 100 times the diameter of the copper wire (from the pay-off end to the die core of the machine head, they are all in a straight line to avoid deformation of the single copper wire under stress). The three copper wires are gathered at one place by the three magnetic eyes of the converging die and rolled and shaped by a double-pressure device regulated by a precision air pressure valve. The lower roller of the double-pressure device is provided with a groove, the chamfers on both sides are smoothly transitioned, and the upper part is provided with a convex protrusion, which fits perfectly with the groove. The precision air pressure valve can ensure that the crimping accuracy is 0.01mm, ensuring that the force of the single copper wire is within the controllable range during shaping. Limit devices are installed at the inlet and outlet of the double-pressure device, and an automatic calibration function is added to achieve that the inlet, outlet and crimping are always in a straight line, and the outlet is infinitely close to the extrusion die core, completely eliminating the hidden dangers of broken wires and mold blocking. At the same time, the mold core selects a rectangular structure for further shaping, and the mold sleeve is treated with a 0.1mm arc protruding on the long axis part to solve the problem of indentation due to pressure after extrusion, ensuring that the insulated wire after molding has a rectangular structure.

[0032] 2) The copper-plated steel wire is paid out in parallel, using an active pay-off device, and then straightened to avoid mold blocking and debonding caused by micro-bending. The straightener uses 24 sets of straightening wheels placed crosswise, and the diameter of the straightening wheel is not more than 5 times the diameter of the steel wire. After straightening, it is preheated at 80°C to improve the bonding strength between the steel wire bonding layer and the copper-plated steel wire. After the steel wire is extruded, it is cooled synchronously with the optical fiber. This device contains an optical fiber channel with a temperature of 80°C for optical fiber preheating; the channel is filled with convection argon to automatically transport the optical fiber and reduce optical fiber oxidation; the outer side of the optical fiber channel is the steel wire bonding layer cooling area, and the temperature in this area is The temperature is 80℃, and this section is added to ensure that the bonding layer and the steel wire are fully bonded; then it enters the second cooling device of the steel wire bonding layer, which contains an optical fiber channel. The temperature in the optical fiber channel is also 80℃, which is used for optical fiber preheating; the channel is filled with convection argon gas to automatically transmit the optical fiber and reduce optical fiber oxidation; the outer side of the optical fiber channel is the cooling area of ​​the steel wire bonding layer, which is filled with 30℃ compressed air to rapidly cool the steel wire bonding layer to avoid the liquid bonding layer clogging the mold core; at the same time, the surface temperature of the steel wire bonding layer can be kept above 30℃, which improves the bonding strength between the steel wire bonding layer and the sheath material and ensures that the steel wire extraction force is above 100N. Then the butterfly optical cable is extruded.

[0033] 3) During the extrusion of the steel wire bonding layer, the glue G103, the inner skin material XK1059 and EAA need to be stirred evenly in a mixer for 10 minutes at a temperature of 50°C and a ratio of 1:2.5:3 to ensure that the extruded steel wire bonding layer is compatible with the sheath and that the surface of the steel wire is smooth and free of residue after the sheath is peeled off.

[0034] 4) The copper-plated steel wire and the optical fiber are extruded through a die, and the die temperature is (150°C, 160°C, 165°C). In order to improve the bonding strength between the steel wire bonding layer and the sheath material, a 1-meter preheating device is added between the die and the water tank, and the preheating temperature is 100°C.

[0035] 5) The cabling machine was optimized, and an active pay-off device was added to place the positioning support element. A positioning device was installed at the double wheel exit to prevent the positioning support element from twisting. The two butterfly optical cables and two rectangular insulated wires in the optoelectronic hybrid cable were paid out using a twisting cage. The pay-off frame and the twisting table were at the same angle, and no corners were allowed to appear, avoiding the twisting of the butterfly optical cable. A correction positioning mold was installed in front of the twisting table. The positioning mold was designed in a rectangular shape according to the size of the butterfly optical cable and the insulated wire. The insulated wire, butterfly optical cable and positioning support element entered the twisting mold after passing through the positioning mold. The twisting mold was designed separately. The design is divided into two sections. The first section is used for twisting rectangular insulated wires and positioning support elements. The positioning holes designed according to the size of the rectangular insulated wires solve the hidden danger of dislocation of the insulated wires. When each rectangular insulated wire is located in the positioning support element, the cabling machine uses a pneumatic device to press a pressing plate on the upper and lower parts of the rectangular insulated wire to position the rectangular insulated wire. After the pressing plate is in place, it enters the second section of the twisting die. The positioning holes are designed according to the size of the butterfly cable, which solves the hidden dangers of dislocation and flipping of the butterfly optical cable. After the butterfly optical cable is in place, the flame-retardant filling rope is filled in the empty spaces on the four sides of the cable core, and then it is immediately wrapped and then put on the coil.

[0036] 6) After the cable core is completed, the sheath is extruded. Before entering the machine head for extrusion, it first passes through a talcum powder device to ensure the extraction force between the sheaths, and then is gradually extruded, cooled, and wound up.

[0037] The photoelectric hybrid cable prepared by the method of the present invention is as follows Figure 1 As shown, the center of the optoelectronic hybrid cable includes a rectangular insulating wire symmetrically arranged up and down, and butterfly optical cables are symmetrically arranged on the left and right sides of the rectangular insulating wire; the rectangular insulating wire and the butterfly optical cable form a cross-symmetrical structure, and four flame-retardant filling ropes 1 are also arranged at the four corners of the cross-symmetrical structure. The rectangular insulating wire and the butterfly optical cable are wrapped with a layer of fire-resistant tape 9; the fire-resistant tape 9 is also extruded with a second flame-retardant polyvinyl chloride insulation layer 10; the thickness of the fire-resistant tape 9 is 0.4mm.

[0038] The rectangular insulated wire is positioned by a positioning support element 6, and the positioning support element 6 supports the butterfly optical cable; the rectangular insulated wire includes three strands of special-shaped twisted copper wires 7 and a first flame-retardant polyvinyl chloride insulation layer 8 coated on the outside of the special-shaped twisted copper wires 7; the butterfly optical cable includes an optical fiber 4, and a copper-plated steel wire 3 symmetrically arranged above and below the optical fiber 4, and a steel wire bonding layer 2 is extruded on the surface of the copper-plated steel wire 3; the optical fiber 4 and the copper-plated steel wire 3 are extruded with a flame-retardant sheath 5; the flame-retardant sheath 5 is pressed against the side of the positioning support element 6 without a stripping opening, and the flame-retardant sheath 5 is provided with a stripping opening on the side away from the positioning support element 6, the stripping opening angle is reduced to 45°, and the depth is simultaneously reduced to 1.5 mm.

[0039] The above description is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements without departing from the principle of the present invention, and these improvements should also be regarded as within the protection scope of the present invention.

Claims

1. An optoelectronic hybrid cable, characterized in that: The center of the optical-electric hybrid cable includes a rectangular insulating wire symmetrically arranged up and down, and butterfly optical cables are symmetrically arranged on the left and right sides of the rectangular insulating wire; The rectangular insulated wire is positioned by a positioning support element (6), and the positioning support element (6) supports the butterfly-shaped optical cable; The rectangular insulated wire comprises three strands of special-shaped twisted copper wires (7) and a first flame-retardant polyvinyl chloride insulation layer (8) coated on the outside of the special-shaped twisted copper wires (7); The butterfly optical cable comprises an optical fiber (4), and a copper-plated steel wire (3) symmetrically arranged above and below the optical fiber (4); a steel wire bonding layer (2) is extruded on the surface of the copper-plated steel wire (3); the optical fiber (4) and the copper-plated steel wire (3) are extruded with a flame-retardant sheath (5); the side of the flame-retardant sheath (5) pressed against the positioning support element (6) has no stripping opening, and the side of the flame-retardant sheath (5) away from the positioning support element (6) is provided with a stripping opening; the positioning support element (6) is higher than the center position of the rectangular insulated wire, and the positioning support element (6) is higher than the butterfly optical cable.

2. The optical-electric hybrid cable according to claim 1, characterized in that: The rectangular insulated wire and the butterfly-shaped optical cable form a cross-symmetrical structure, and four flame-retardant filling ropes (1) are also arranged at the four corners of the cross-symmetrical structure.

3. The optical-electric hybrid cable according to claim 1, characterized in that: The stripping opening angle of the butterfly optical cable is reduced to 45°, and the depth is simultaneously reduced to 1.5 mm.

4. The optical-electric hybrid cable according to claim 1, characterized in that: The rectangular insulated wire and the butterfly optical cable are wrapped with a layer of fire-resistant tape (9); a second flame-retardant polyvinyl chloride insulation layer (10) is extruded outside the fire-resistant tape (9); the thickness of the fire-resistant tape (9) is 0.4 mm.

5. The optical-electric hybrid cable according to claim 1, characterized in that: The three strands of special-shaped twisted copper wires (7) arranged in the rectangular insulated wire are elliptical twisted copper wires.

6. A method for preparing an optoelectronic hybrid cable according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1, preparation of rectangular insulated wire: select three strands of special-shaped twisted copper wire (7), use active pay-off, place them in parallel, the diameter of the guide wheel is greater than 100 times the diameter of the copper wire, and they are all on a straight line from the pay-off end to the die core of the die head. The three strands of copper wire are gathered at one place by three magnetic eyes of the wire-converging die, and are rolled and shaped by a double-pressure device regulated by a precision air pressure valve; limit devices are respectively installed at the inlet and outlet of the double-pressure device, and an automatic calibration function is added; at the same time, the die core is selected to have a rectangular structure for further shaping, and the die sleeve protrudes 0.1 mm at the long axis part for arc processing; Step 2: The copper-plated steel wire (3) is released in parallel using an active pay-off device, and then straightened; after straightening, it is preheated at a temperature of 80° C. After extrusion, the steel wire enters a first-stage cooling device of the steel wire bonding layer synchronously with the optical fiber; then enters a second-stage cooling device of the steel wire bonding layer (2), and then the butterfly optical cable is extruded; Step 3: In the extrusion of the steel wire bonding layer, a mass ratio of 1: Glue G103, inner skin material XK1059 and EAA in a ratio of 2.5:3 were stirred at a constant speed in a mixer for 10 minutes at a temperature of 50°C; Step 4: Extruding the copper-plated steel wire (3) and the optical fiber (4): Extruding a flame-retardant sheath (5) on the optical fiber and the copper-plated steel wire through a die, the die head temperature is 150° C., 160° C., and 165° C.; in order to improve the bonding strength between the steel wire bonding layer and the flame-retardant sheath, adding a preheating device between the die head and the water tank for preheating treatment, the preheating temperature is 100° C.; Step 5. An active pay-off device is set in the cabling machine to place the positioning support element, and a positioning device is installed at the double-wheel exit; the two butterfly optical cables and two rectangular insulated wires in the optoelectronic hybrid cable are paid out by a twisting cage, and the pay-off frame and the twisting table are at the same angle, and no corners are allowed. A correction positioning mold is installed in front of the twisting table. The positioning mold is designed in a rectangular shape according to the size of the butterfly optical cable and the insulated wire; the rectangular insulated wire, butterfly optical cable and positioning support element enter the twisting mold after passing through the positioning mold. The twisting mold is designed separately and divided into two sections. The first section is used for The rectangular insulated wires and the positioning support element are twisted, and the positioning holes are designed according to the size of the rectangular insulated wires, thereby solving the hidden danger of the insulated wires being misplaced. When the rectangular insulated wires are placed in the positioning support element, the cabling machine uses a pneumatic device to press a pressing plate on the upper and lower sides of the rectangular insulated wires to position the rectangular insulated wires. After the pressing plates are placed, the second section of the twisting die is entered, and the positioning holes are designed according to the size of the butterfly cable, thereby solving the hidden dangers of the butterfly optical cable being misplaced or flipped. After the butterfly optical cable is placed, the flame-retardant filling rope (1) is filled in the empty spaces on the four sides of the cable core, and then the cable core is immediately wrapped, and then the cable core is coiled. Step 6: After the cable core is completed, the sheath is extruded, that is, a layer of fire-resistant tape (9) and a second flame-retardant polyvinyl chloride insulation layer (10) are extruded in sequence, followed by cooling and winding.

7. The method for preparing a photoelectric hybrid cable according to claim 6, characterized in that: The lower roller of the double-pressing device in step one is provided with a groove, the chamfers on both sides are smoothly transitioned, and the upper part is provided with a convex protrusion that fits perfectly with the groove. The crimping accuracy of the precision air pressure valve is 0.01mm.

8. The method for preparing a photoelectric hybrid cable according to claim 6, characterized in that: In the step 2, the straightener uses 24 sets of straightening wheels placed crosswise, and the diameter of the straightening wheel is not greater than 5 times the diameter of the steel wire.

9. The method for preparing a photoelectric hybrid cable according to claim 6, characterized in that: The cooling device for the steel wire bonding layer in step 2 contains an optical fiber channel, the temperature in the optical fiber channel is 80°C, and is used for preheating the optical fiber; the channel is filled with convective argon gas, which is used to automatically transport the optical fiber and reduce optical fiber oxidation; the outer side of the optical fiber channel is a cooling area for the steel wire bonding layer (2), and the temperature in this area is 80°C; The two-stage cooling device of the steel wire bonding layer (2) comprises an optical fiber channel, the temperature in the optical fiber channel is uniformly 80°C; the optical fiber channel is filled with convective argon gas; the outer side of the optical fiber channel is a steel wire bonding layer cooling area, which is filled with 30°C compressed air; and at the same time, the surface temperature of the steel wire bonding layer is maintained at above 30°C.

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