Damping rubber sleeve cable structure and preparation method thereof

Abstract

The invention discloses a damping rubber sleeve cable structure and a preparation method thereof. The damping rubber sleeve cable structure comprises a plurality of wire cores, a damping layer, a reinforcing layer and an outer sheath, the cable comprises a plurality of cable cores, a damping layer is filled outside the plurality of cable cores, the reinforcing layer is woven outside the plurality of cable cores and the damping layer by adopting aramid yarns, the outer sheath is coated outside the reinforcing layer, and the surface of the outer sheath is provided with a groove-shaped structure which is spirally distributed along the longitudinal direction of the cable. Cable vibration can be effectively inhibited, vibration energy can be consumed and absorbed, the vibration amplitude and frequency of the cable can be significantly reduced, the risk of fracture of the rubber sleeve cable due to fatigue can be reduced, and the service life of the cable can be prolonged; and the occurrence rate of short circuit and other faults caused by vibration can be reduced, safe and stable operation of a power transmission line is ensured, and the reliability of power supply is improved.

Description

Technical Field

[0001] The invention relates to the technical field of cables, and in particular to a damping rubber sheathed cable structure and a preparation method thereof. Background Art

[0002] Rubber sheathed flexible cables are widely used in various electrical equipment. They can be used as mobile power cables for household appliances, electric machinery, electrical devices and appliances. They can also be used as power cables for agricultural electrification equipment, port machinery, large agricultural water irrigation and drainage stations, and electric welding machines. They can be used in indoor and outdoor environments. After the cables are laid, they will be disturbed by various external mechanical and natural forces during use, which will affect the failure of the cables and the stability of the circuit system. For example, the following application scenarios:

[0003] 1. Industrial precision equipment and industrial robots require very high motion accuracy. If the internal signal transmission cables and power cables are affected by vibration, it may cause signal errors and power instability. Damping cables can be used in the joints and internal wiring of industrial robots to reduce the impact of vibration on cables during robot movement and improve the robot's work efficiency and accuracy.

[0004] 2. Wind turbines in wind farms will vibrate when they are running, and the wind force in the environment is usually strong. The use of damping cables for connecting wind turbines and booster stations can reduce the vibration of cables caused by wind and wind, reduce the failure rate of cables, and improve the stability of the wind farm power generation system.

[0005] 3. In urban rail transit systems such as subways and light rails, trains will generate vibrations when running on the track. These vibrations will affect the power supply cables and signal transmission cables. Damping cables are used in the power supply system and signal system of rail transit to reduce the damage to the cables caused by vibrations, ensure the normal power supply and signal transmission of the trains, and improve the safety and comfort of rail transit.

[0006] 4. High-rise buildings and intelligent buildings: The electrical systems of high-rise buildings are relatively complex, and elevators, air conditioners, ventilation equipment, etc. will generate vibrations when in operation. Damping cables can be used for power supply and signal transmission of these devices, reducing damage to cables caused by vibrations and improving the stability of building electrical systems. Damping cables can be used in the wiring system of intelligent buildings to ensure accurate transmission of signals from sensors, controllers, and communication equipment in intelligent buildings, and to ensure the normal operation of intelligent functions of intelligent buildings.

[0007] 5. Communication base stations and data centers: Antennas and radio frequency equipment in communication base stations may be affected by external factors (such as wind, vibration of nearby equipment, etc.) and vibrate during operation. Damping cables are used for signal transmission and power supply of base stations, which can reduce the interference of vibration on cables, ensure the quality of communication signals, and improve the communication efficiency of base stations.

[0008] 6. Cables used in underwater production operations are in a water flow vibration environment for a long time. Ordinary rubber-sheathed cables are prone to up and down vibrations. Rubber-sheathed cables are at risk of breaking due to fatigue, resulting in a short circuit.

[0009] The existing damping cable is a cylindrical cross-section structure. This alternating vortex will generate a periodic pulsating pressure on the column in the downstream and transverse directions. If the column is elastically supported at this time, or the flexible tube allows elastic deformation, the pulsating fluid force will induce periodic vibration of the column (tube), and this regular columnar vibration will in turn change the vortex emission pattern of its wake. This problem of fluid-structure interaction is called "vortex-induced vibration". When dealing with vortex-induced vibration problems, considering the fluid and solid elastic system as a unified dynamic system and finding the coupling conditions between the two are important keys to solving this problem. In the process of vortex-induced vibration, the dynamic pressure of the fluid is an external load acting on the elastic system. The magnitude of the dynamic pressure depends on the displacement, velocity and acceleration of the vibration of the elastic system; on the other hand, the action of the fluid dynamic pressure will change the displacement, velocity and acceleration of the vibration of the elastic system. The physical properties of this interaction are manifested as the coupling phenomenon of the fluid to the elastic system in terms of inertia, damping and elasticity.

[0010] When the natural frequency of the damping cable is close to the frequency of vortex emission, the structure will be damaged by resonance. This phenomenon is prone to occur in tall structures. Therefore, this vortex-induced vibration is extremely harmful and measures must be taken to prevent it from happening. Summary of the invention

[0011] In view of the problems existing in the prior art, the present invention provides a damping rubber sheathed cable structure and a preparation method thereof, which can effectively suppress cable vibration, consume and absorb vibration energy, significantly reduce the vibration amplitude and frequency of the cable, reduce the risk of breakage of the rubber sheathed cable due to fatigue, and extend the service life of the cable; it can also reduce the incidence of faults such as short circuits caused by vibration, ensure the safe and stable operation of transmission lines, and improve the reliability of power supply.

[0012] The technical solution of the present invention is as follows:

[0013] In a first aspect of the present invention, a damped rubber sheathed cable structure is provided, comprising a plurality of wire cores, a damping layer, a reinforcement layer and an outer sheath; the plurality of wire cores are filled with a damping layer on the outside, the reinforcement layer is woven with aramid yarn on the outside of the plurality of wire cores and the damping layer, the outer sheath is covered on the outside of the reinforcement layer, and the surface of the outer sheath is provided with a groove-like structure spirally distributed along the longitudinal direction of the cable.

[0014] In some embodiments of the present invention, the damping layer is made of damping material and extruded into a special-shaped structure of corresponding size according to the number and size of the wire cores.

[0015] In some embodiments of the present invention, the damping layer is provided with an arc-shaped opening facing the reinforcement layer, and the arc-shaped opening is filled with optical fibers or steel cables.

[0016] In some embodiments of the present invention, the resistance value of the damping material is 16 kΩ / m±30%.

[0017] In some embodiments of the present invention, a plurality of ridges are provided on the surface of the outer sheath, a groove-like structure is formed between two adjacent ridges, adjacent ridges are distributed at equal intervals, and are spirally wound at equal pitches along the longitudinal direction of the cable.

[0018] In some embodiments of the present invention, the braiding density of the aramid filaments is 60-80%.

[0019] In a second aspect of the present invention, a method for preparing a damped rubber sheathed cable is provided, comprising the following steps:

[0020] The shape of the damping layer is drawn according to the number and size of the wire cores, a corresponding mold is designed according to the shape of the damping layer, and the damping layer of the matching shape is extruded by the mold as a filling material;

[0021] When multiple cores are cabled, the damping layer is filled between the cores;

[0022] The aromatic wheel wire is woven onto the damping layer and the outside of the wire core by a braiding machine as a reinforcement layer;

[0023] An extrusion die with grooves is used to rotationally extrude an outer sheath to wrap the cable, so that ridges are formed on the surface of the outer sheath.

[0024] In some embodiments of the present invention, when weaving the reinforcement layer, a vertical braiding machine and a horizontal braiding machine are selected, and the braiding density is set to 60%-80% according to the force applied to the cable. The pitch of the braided strands is calculated based on the braiding density to produce a suitable product.

[0025] In some embodiments of the present invention, during the production of the outer sheath, gears are fixed to the outer surface of the extrusion die, and the rotation of the gears drives the extrusion die to rotate at a set speed to ensure that spiral ridges are evenly formed on the surface of the outer sheath when the cable is extruded.

[0026] In some embodiments of the present invention, the ridges on the outer sheath disrupt the regular discharge of vortices in the wake field of the cable, thereby changing the wake field of the cable.

[0027] One or more technical solutions of the present invention have the following beneficial effects:

[0028] (1) The present invention adopts a damping material profile structure as a filling component between cable cores, and reduces the influence of vortex-induced vibration on the cable by improving the damping layer, the reinforcement layer and the outer sheath. Specifically, when the cables are twisted into cables, the damping material is filled between the cores to absorb and dissipate the vibration, thereby converting it into heat and conducting it to the laying environment along with the cable body; the strength of the cable is strengthened by weaving aramid yarns, which resists the damping force borne by the cable, and the lightweight aramid material will not increase the weight of the cable body and have a negative impact; by arranging a proportional groove-like structure on the outside of the outer sheath and distributing it in a spiral shape in the longitudinal direction of the cable and circulating at equal pitches, the wake field of the component can be improved.

[0029] (2) The damping rubber-sheathed cable proposed in the present invention can effectively suppress cable vibration, consume and absorb vibration energy, significantly reduce the vibration amplitude and frequency of the cable, reduce the risk of rubber-sheathed cables breaking due to fatigue, and extend the service life of the cable. This reduces the incidence of short circuits and other faults caused by vibration, ensures the safe and stable operation of the transmission line, and improves the reliability of power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the cross-sectional structure of the damping rubber sheathed cable of the present invention;

[0031] Figure 2 It is a schematic structural diagram of the damping layer of the damping rubber sheathed cable of the present invention;

[0032] Figure 3 It is a schematic structural diagram of the outer sheath of the damping rubber sheathed cable of the present invention;

[0033] Figure 4 A side view of an outer sheath extrusion die of the present invention;

[0034] Figure 5 It is a cross-sectional view along the axial direction of the outer sheath extrusion die of the present invention.

[0035] In the figure: 1, wire core; 101, wire core insulation layer; 2, damping layer; 201, arc-shaped opening; 3, reinforcement layer; 4, outer sheath; 401, ridge; 402, groove-like structure; 5, extrusion die; 501, outer sheath extrusion port; 502, gear; 503, groove. DETAILED DESCRIPTION

[0036] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0037] Example 1

[0038] In view of the damage caused by vortex-induced oscillation to the cable structure, the present invention proposes to adopt the following three measures to effectively prevent vortex-induced oscillation: First, the rigid reinforcement of the component, or the increase of its size to improve its rigidity, change the natural frequency of the component, and prevent it from being close to the vortex emission frequency. Second, find a way to change the wake field behind the component to destroy the regular discharge of the vortex in the wake field, such as installing spiral vertical plates on the structure and changing the cross-sectional shape of the structure. Third, the damping layer is set: it is the key part of the damping cable, usually made of materials with certain resistance and inductance values, such as the damping layer resistance value of the resistive damping line is generally 16kΩ / m±30%, and its function is to suppress the electromagnetic interference generated by the system and reduce the impact on other electronic equipment.

[0039] Specifically, in a typical embodiment of the present invention, a damping rubber sheathed cable structure is proposed, such as Figures 1 to 3 As shown, it includes multiple cores 1, a damping layer 2, a reinforcement layer 3 and an outer sheath 4; the multiple cores 1 are filled with the damping layer 2, the reinforcement layer 3 is woven with aramid yarn on the outside of the multiple cores 1 and the damping layer 2, the outer sheath 4 is covered on the outside of the reinforcement layer 3, and the surface of the outer sheath 4 is provided with a groove structure 402 spirally distributed along the longitudinal direction of the cable.

[0040] In this embodiment, the damping layer 2 uses damping material to extrude a special-shaped structure of corresponding size according to the number and size of the wire cores. Specifically, it is usually made of a material with a certain resistance value, such as a modified rubber material, and the resistance value of the damping material is 16kΩ / m±30%. When conventional cables are cabled, filling ropes are used to fill the cables to make them round. In this embodiment, extruded damping material is used to form a special-shaped structure, which is filled to the outside between the wire cores when cabled. The damping layer absorbs and dissipates vibrations and converts them into heat, which is conducted to the laying environment along with the cable body, while the internal gaps between the cables are still filled with filling ropes. Furthermore, the damping layer 2 is provided with an arc-shaped opening 201 facing the reinforcement layer 3. The arc-shaped opening 201 increases the flexibility of the cable and allows the cable to deform and move to a certain extent, thereby reducing vortex-induced vibration. Optical fiber or steel wire rope (whose cross-sectional area is smaller than that of the arc-shaped opening to ensure that there is a gap to allow the cable to deform) can be filled in the arc-shaped opening 201 as needed. The signal of the cable can be monitored by filling the optical fiber, and the strength of the cable can be enhanced by filling the steel wire rope. This is suitable for places with high requirements on cable strength.

[0041] In this embodiment, a braiding machine is used to braid aramid yarn outside the cable core as a reinforcement layer. The braided aramid products inherit the high strength and high modulus characteristics of aramid fiber. Taking aramid rope as an example, its strength is higher than that of steel wire rope with the same diameter. It can be used in vertical laying and long-distance overhead laying where the cable strength is extremely high. It can withstand huge tension without breaking. Specifically, the braiding density of the aramid yarn is 60-80%. If the braiding density is less than 60%, it cannot play a damping role. Since the price of aramid yarn is relatively high, when the braiding density is higher than 80%, the cost is relatively high. Within this braiding density range, it can provide appropriate damping force and ensure that the cost is not too high.

[0042] In this embodiment, the surface of the outer sheath 4 is provided with a plurality of ridges 401, and a groove-like structure 402 is formed between two adjacent ridges 401. The adjacent ridges are evenly spaced and spirally wound at equal pitches along the longitudinal direction of the cable. The outer sheath of a conventional cable is a plastic extrusion coating on the surface of the cable, and the surface is smooth. The outer sheath of the cable provided in this embodiment adopts a special-shaped structure, which is specifically manifested in that an equal-proportional groove-like structure is provided on the outside of the outer sheath, and is spirally distributed in the longitudinal direction of the cable, circulated at equal pitches, and the grooves are used to improve the wake field of the component. In a specific embodiment, 12 ridges are provided, and the angle between two adjacent ridges in the circumferential direction is 30°.

[0043] The damping rubber sheathed cable structure provided in the present embodiment adopts damping material extruded into a special-shaped structure as a filling component, which is filled between the cores when the cables are twisted into cables, absorbs and dissipates vibrations, thereby converting them into heat and conducting them into the laying environment along with the cable body; the strength of the cable is reinforced by weaving aramid yarns, which resists the damping force borne by the cable, and the lightweight aramid material will not increase the weight of the cable body and have a negative impact; an equal-proportional groove-like structure is arranged on the outside of the outer sheath, and is spirally distributed in the longitudinal direction of the cable, with equal pitch circulation, which can improve the wake field of the component; the influence of vortex-induced vibration on the cable is reduced by improving the damping layer, the reinforcement layer and the outer sheath.

[0044] Example 2

[0045] In a typical embodiment of the present invention, a method for preparing a damped rubber sheathed cable is provided, comprising the following steps:

[0046] The shape of the damping layer is drawn according to the number and size of the wire cores, a corresponding mold is designed according to the shape of the damping layer, and the damping layer of the matching shape is extruded by the mold as a filling material;

[0047] When multiple cores are cabled, the damping layer is filled between the cores; specifically, when braiding the reinforcement layer, a vertical braiding machine (commonly 16 and 24 spindles) and a horizontal braiding machine (commonly 36 and 48 spindles) are selected, and the braiding density is set to 60%-80% according to the force on the cable. The pitch of the strand braiding is calculated according to the braiding density to produce a suitable product.

[0048] The braid coverage density is calculated according to the following formula:

[0049] P=(2p-p 2 )×100

[0050] Where, P is the coverage density of the braided layer, %; p is the unidirectional coverage factor.

[0051]

[0052] Where D is the pitch diameter of the braided layer, mm; d is the diameter of the braided aramid yarn; m is the number of spindles in the same direction of the braiding machine; n is the number of braided wires per spindle; L is the braiding pitch, mm.

[0053] The aromatic wheel wire is woven onto the damping layer and the outside of the wire core by a braiding machine as a reinforcement layer;

[0054] The shape of the damping layer is drawn according to the number and size of the wire cores, a corresponding mold is designed according to the shape of the damping layer, and the damping layer of the matching shape is extruded by the mold as a filling material;

[0055] When multiple cores are cabled, the damping layer is filled between the cores;

[0056] The aromatic wheel wire is woven onto the damping layer and the outside of the wire core by a braiding machine as a reinforcement layer;

[0057] The cable is wrapped with an outer sheath by rotating and extruding an extrusion die with grooves, so that ridges are formed on the surface of the outer sheath; specifically, during the production process of the outer sheath, Figure 5 As shown, a gear 502 is fixed on the outer surface of the extrusion die 5, and the rotation of the gear drives the extrusion die to rotate at a set speed, and a groove 503 is provided at the outer sheath extrusion port 501 to ensure that spiral ridges are uniformly formed on the surface of the outer sheath when the cable is extruded. The ridges on the outer sheath destroy the regular discharge of the vortex in the wake field of the cable, thereby changing the wake field of the cable.

[0058] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A damping rubber sheathed cable structure, characterized in that: It includes multiple wire cores, a damping layer, a reinforcement layer and an outer sheath; the outer part of the multiple wire cores is filled with a damping layer, the reinforcement layer is woven with aramid yarn on the outside of the multiple wire cores and the damping layer, the outer sheath is covered on the outside of the reinforcement layer, and the surface of the outer sheath is provided with a groove structure spirally distributed along the longitudinal direction of the cable.

2. The damping rubber sheathed cable structure according to claim 1, characterized in that: The damping layer adopts damping material to extrude a special-shaped structure of corresponding size according to the number and size of the wire cores.

3. The damping rubber sheathed cable structure according to claim 2, characterized in that: The damping layer is provided with an arc-shaped opening facing the reinforcement layer, and the arc-shaped opening is filled with optical fiber or steel wire rope.

4. The damping rubber sheathed cable structure according to claim 2, characterized in that: The resistance value of the damping material is 16 kΩ / m±30%.

5. The damping rubber sheathed cable structure according to claim 1, characterized in that: The outer sheath surface is provided with a plurality of ridges, a groove-shaped structure is formed between two adjacent ridges, the adjacent ridges are distributed at equal intervals, and are spirally wound at equal pitches along the longitudinal direction of the cable.

6. The damping rubber sheathed cable structure according to claim 1, characterized in that: The braiding density of the aramid yarn is 60-80%.

7. A method for preparing a damped rubber-sheathed cable structure according to any one of claims 1 to 6, characterized in that: The following steps are involved: The shape of the damping layer is drawn according to the number and size of the wire cores, a corresponding mold is designed according to the shape of the damping layer, and the damping layer of the matching shape is extruded by the mold as a filling material; When multiple cores are cabled, the damping layer is filled between the cores; The aromatic wheel wire is woven onto the damping layer and the outside of the wire core by a braiding machine as a reinforcement layer; An extrusion die with grooves is used to rotationally extrude an outer sheath to wrap the cable, so that ridges are formed on the surface of the outer sheath.

8. The method for preparing the damped rubber sheathed cable structure according to claim 7, characterized in that: When braiding the reinforcement layer, a vertical braiding machine and a horizontal braiding machine are selected. The braiding density is set to 60%-80% according to the force applied to the cable. The pitch of the braided strands is calculated based on the braiding density in order to produce a suitable product.

9. The method for preparing a damped rubber-sheathed cable structure according to claim 7, characterized in that: During the production of the outer sheath, a gear is fixed on the outer surface of the extrusion die, and the rotation of the gear drives the extrusion die to rotate at a set speed to ensure that spiral ridges are evenly formed on the surface of the outer sheath when the cable is extruded.

10. The method for preparing a damped rubber sheathed cable structure according to claim 9, characterized in that: The ridges on the outer sheath disrupt the regular discharge of vortices in the wake field of the cable, thereby changing the wake field of the cable.

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