Production process of mine cable against signal interference

Abstract

The present application belongs to the technical field of mining cable manufacturing, and specifically discloses a production process for a mining cable resistant to signal interference, which comprises a cable core after cabling; a support sheath is sleeved on the outer layer of the cable core, and a semiconductive colloid is filled between the inner wall of the support sheath and the cable core; a composite shielding layer is made outside the support sheath, so that the outer wall of the support sheath is in contact with the inner surface of the composite shielding layer; in sequence, inner sheath extrusion, armor layer setting and outer sheath extrusion are performed outside the composite shielding layer; wherein the outer wall of the support sheath is provided with corrugated protrusions extending in a spiral shape along the axial direction; the radial height difference between the wave crest and the wave trough of the corrugated protrusions is 5%-10% of the diameter of the cable core; the present application effectively solves the technical problem that the shielding layer in the prior art produces micro-cracks or local fractures due to directly bearing mechanical stress, resulting in a decrease in shielding effectiveness, and significantly improves the effect of the cable's resistance to signal interference.

Description

Technical Field

[0001] This invention belongs to the field of mining cable manufacturing technology, and in particular relates to a production process for preventing signal interference in mining cables. Background Technology

[0002] Mining cables operate in complex and harsh environments such as mines, where they are exposed to severe conditions such as high humidity, dust pollution, rock compression, and frequent mechanical vibration. To ensure the reliability of communication and power transmission, existing technologies generally adopt a structure in which a metal shielding layer is directly installed on the outer layer of the cable core, such as by wrapping with aluminum-plastic composite tape or braiding a layer of tin-plated copper wire to achieve electromagnetic interference protection.

[0003] However, the shielding layer is in direct contact with the cable core and lacks an effective mechanical stress buffering mechanism. When the cable is subjected to radial impact, such as being run over by a mine car or falling rocks, the rigid shielding material cannot disperse the local load, resulting in microcracks or fractures. During repeated bending, the shielding layer's lack of elastic deformation capacity accelerates fatigue damage. Physical damage to the shielding layer significantly reduces its electromagnetic shielding effectiveness, allowing external electromagnetic interference to easily penetrate the cable core, causing signal distortion, communication interruptions, and even control system malfunctions, seriously threatening mine operation safety. Furthermore, existing shielding structures struggle to maintain long-term stable protective performance under dynamic loads, failing to meet the dual requirements of mechanical strength and electromagnetic compatibility for mining cables.

[0004] To address the aforementioned issues, existing technologies urgently need improvement. Summary of the Invention

[0005] The purpose of this invention is to provide a manufacturing process for anti-signal interference of mining cables, so as to solve the technical problem in the prior art that the shielding layer produces micro-cracks or local fractures due to direct mechanical stress, resulting in a decrease in shielding effectiveness, and significantly improve the anti-signal interference capability of the cable.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: a manufacturing process for anti-signal interference mining cables, comprising the following steps:

[0007] Obtain the cable core after cabling;

[0008] A support sheath is fitted over the outer layer of the cable core, and semi-conductive colloid is filled between the inner wall of the support sheath and the cable core.

[0009] A composite shielding layer is fabricated on the outside of the support sheath, so that the outer wall of the support sheath is in contact with the inner surface of the composite shielding layer.

[0010] The inner sheath extrusion, armoring, and outer sheath extrusion are performed sequentially outside the composite shielding layer.

[0011] Among them, the outer wall of the support sheath is provided with corrugated protrusions that extend in a spiral shape along the axial direction, so as to disperse the load through the elastic deformation of the crest when the cable is subjected to radial impact, and to buffer and absorb energy when bending by increasing the spacing between the troughs and flattening the crests; the radial height difference between the crests and troughs of the corrugated protrusions is 5%-10% of the cable core diameter.

[0012] Furthermore, the composite shielding layer includes an aluminum-plastic composite strip and a tin-plated copper wire braided layer arranged sequentially from the inside to the outside. The aluminum-plastic composite strip has a metal aluminum foil side and is longitudinally wrapped around the support sleeve with the metal aluminum foil side facing the support sleeve. The tin-plated copper wire braided layer is woven on the outer surface of the aluminum-plastic composite strip.

[0013] Furthermore, the aluminum foil surface of the aluminum-plastic composite strip is pressed with periodic sinusoidal ripples.

[0014] Furthermore, the cable core is obtained through the following steps:

[0015] Multiple conductors are twisted together in a concentric layer pattern, and molten insulating material is uniformly extruded and wrapped around the conductors through an extruder to obtain an insulated wire core.

[0016] Multiple insulated wire cores are shielded by phase;

[0017] After phase shielding, the insulated wire cores are stranded into a cable according to the layer arrangement rules and the set cable section diameter ratio, and a pad core is placed at the center of the stranding.

[0018] The stranded cable is made using the SZ stranding process.

[0019] Furthermore, the extrusion temperature of the sheath is controlled by the following methods:

[0020] Collect the real-time temperature during the extrusion process of mining cable sheaths and calculate its deviation from the set target temperature;

[0021] Based on the asymmetric hysteresis interval and the continuous over-limit counter, the deviation is judged to obtain the current operating state;

[0022] When the current operating state is over-limit correction, the set target temperature for the next cycle is smoothly corrected based on the preset correction step size, and control commands are output to the extruder heating module.

[0023] Furthermore, the update process of the continuous overshoot counter satisfies the following formula:

[0024] ;

[0025] in, For the continuous out-of-bounds counter in the nth sampling period, This is the maximum value of the counter. The deviation between the real-time temperature and the set target temperature in the nth sampling period. This is the lower inner threshold of the outer hysteresis window. The attenuation coefficient is... , This is an indicator function.

[0026] Furthermore, the state determination is based on the following formula:

[0027]

[0028] in, This represents the current operating state corresponding to the nth sampling period. This represents the deviation between the real-time temperature and the set target temperature corresponding to the nth sampling period. This is the lower inner threshold of the outer hysteresis window. The upper limit threshold of the outer hysteresis window. For the continuous out-of-bounds counter in the nth sampling period, To confirm the threshold.

[0029] Furthermore, the target temperature for the next cycle is smoothly corrected based on a preset correction step size using the following formula:

[0030] ;

[0031] in, The target temperature is set for the (n+1)th sampling period. The constant target temperature set at the beginning of the process. For single correction step size, The deviation between the real-time temperature and the set target temperature in the nth sampling period. For symbolic functions, This is an indicator function.

[0032] Furthermore, the support sheath is made of a semi-conductive elastomer material, and multiple corrugated protrusions are evenly distributed around the outer wall of the support sheath. The pitch of the corrugated protrusions on the outer wall of the support sheath is inversely proportional to the cable core pitch ratio.

[0033] Furthermore, the braiding density of the tin-plated copper wire braid layer is not less than 85%.

[0034] The beneficial effects of this technical solution are as follows: By setting a support sheath made of semi-conductive elastomer with helical corrugated protrusions, when the cable is subjected to radial impact, the crests of the corrugated protrusions are first compressed and undergo elastic deformation, converting the point load into dispersed compression along the axial and circumferential directions of the sheath, thus avoiding the composite shielding layer from directly bearing impact stress. When the cable bends, the spacing between the troughs on the tensile side increases to store deformation energy, while the crests on the compression side are flattened to buffer and absorb energy, thereby preventing the composite shielding layer from developing sharp bending curvatures. At the same time, the semi-conductive properties of the support sheath and the semi-conductive colloid filling inside ensure the continuity of the cable's electric field, avoiding electric field distortion caused by shielding layer displacement, thus effectively solving the technical problem in the prior art where the shielding layer directly bears mechanical stress, resulting in microcracks or local fractures and a decrease in shielding effectiveness. Meanwhile, the sinusoidal ripples of the aluminum-plastic composite strip in the composite shielding layer, combined with the tin-plated copper wire braiding of the outer layer, enhance the high and low frequency shielding effect. By introducing a hysteresis anti-jitter mechanism with buffer integration function, the problem of frequent extrusion temperature adjustment caused by minor disturbances in the production process is effectively solved, ensuring the forming quality of the sheath, improving process stability, and thus ensuring effective protection of the composite shielding layer of the cable during use, thereby improving the cable's anti-interference capability. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the production process for a mine cable designed to prevent signal interference, according to the present invention.

[0036] Figure 2 This is a schematic diagram of the cross-sectional structure of the cable obtained based on this manufacturing process in an embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram of the supporting sleeve structure in an embodiment of the present invention;

[0038] Figure 4 This is a schematic diagram showing the distribution of sinusoidal ripples on the metal aluminum foil surface of the aluminum-plastic composite strip in an embodiment of the present invention;

[0039] Reference numerals: 1. Cable core; 2. Support sheath; 2. Corrugated protrusion; 201. Aluminum-plastic composite tape; 3. Tinned copper wire braided layer; 4. Inner sheath; 5. Armor layer; 6. Outer sheath; 7. Semi-conductive colloid; 8. Detailed Implementation

[0040] The following detailed description illustrates the specific implementation method:

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] like Figure 1-4 As shown in the figure, this embodiment provides a manufacturing process for anti-signal interference mining cables, which specifically includes the following steps:

[0043] Obtain the cable core 1 after cabling; install a support sheath 2 on the outer layer of the cable core 1, and fill the space between the inner wall of the support sheath 2 and the cable core 1 with semi-conductive colloid 8; fabricate a composite shielding layer on the outside of the support sheath 2, so that the outer wall of the support sheath 2 is in contact with the inner surface of the composite shielding layer; extrude the inner sheath 5, install the armor layer 6, and extrude the outer sheath 7 in sequence on the outside of the composite shielding layer; wherein, the outer wall of the support sheath 2 is provided with corrugated protrusions 201 extending in a spiral shape along the axial direction; the radial height difference between the crest and trough of the corrugated protrusions 201 is 5%-10% of the diameter of the cable core 1.

[0044] Specifically, cable core 1 is the core part of the cable, composed of multiple insulated wire cores twisted together, used to transmit electrical energy or signals; support sheath 2 is a component fitted over cable core 1 to provide mechanical support for the subsequent shielding layer; corrugated protrusions 201 are periodic protrusions extending in a spiral shape along the axial direction on the outer wall of support sheath 2, which, through a special geometric configuration, provide buffering and load distribution functions when the cable is subjected to external stress; in corrugated protrusions 201, the radially outward protruding parts are called crests, and the radially inward concave parts are called troughs, and the alternating arrangement of crests and troughs constitutes the periodic corrugated structure; the diameter of cable core 1 refers to the overall outer diameter of cable core 1 after cabling. The support sheath 2 can be installed in various ways. For example, it can be formed by extrusion molding, where semiconductive material is directly extruded and wrapped around the cable core 1 to form the support sheath 2. The corrugated protrusion 201 can be formed by using an extrusion head with a corresponding mold during the extrusion molding of the support sheath 2. The inner surface of the mold has spiral grooves, which makes the outer wall of the extruded tube form a spiral corrugation. The shape of the corrugation can be a sine wave, square wave, or sawtooth wave, but all must extend spirally along the axial direction. Alternatively, a tubular support sheath 2 can be prefabricated and then installed on the outside of the cable core 1 by pulling or fitting it in. The function of the corrugated protrusion 201 is to disperse the load through the elastic deformation of the crest when the cable is subjected to radial impact, and to buffer and absorb energy when bending by increasing the spacing between the troughs and flattening the crests. When the cable is subjected to radial impact, the crests can undergo elastic deformation, dispersing the impact force to a larger area and avoiding local stress concentration. When the cable bends, the spacing between the troughs can increase, while the crests can be flattened, thereby absorbing bending stress and reducing damage to the inner cable core 1 and the shielding layer. As a preferred embodiment, the radial height difference between the crests and troughs of the corrugated protrusions 201 is 5%-10% of the diameter of the cable core 1, preferably 6% or 8%. If the height difference is too small, the buffering capacity of the corrugations may be insufficient; if the height difference is too large, it may affect the overall size and flexibility of the cable. The radial height difference between the crests and troughs can be precisely controlled by controlling the size and shape of the extrusion die. The material of the support sheath 2 can be a polymer material with certain flexibility and support, such as polyethylene or polypropylene. The filling of the semi-conductive colloid 8 aims to eliminate the air gap between the cable core 1 and the support sheath 2, improve the electric field distribution, and provide auxiliary shielding function. The filling method can be injection, coating, or extrusion. For example, after the support sheath 2 is installed, the semi-conductive colloid 8 can be injected through a pre-drilled hole on the tube to ensure uniform filling. Alternatively, during the extrusion molding of the support sheath 2, the semi-conductive colloid 8 can be simultaneously extruded and filled between the cable core 1 and the tube sheath. This specific arrangement of the support sheath 2 and the semi-conductive colloid 8 is a conventional technical method in this field and will not be elaborated further.The composite shielding layer can be manufactured in various ways. For example, it can be made by wrapping one or more layers of metal strips (such as copper or aluminum strips) spirally around the outer wall of the supporting sheath 2; it can also be made by braiding metal wires (such as copper or steel wires) into a mesh structure and covering the outside of the supporting sheath 2; or it can be made by spraying or dipping conductive materials onto the outer surface of the supporting sheath 2 to form a shielding layer. The inner sheath 5 is usually extruded using materials such as polyvinyl chloride (PVC) or polyethylene (PE), forming a uniform sheath outside the composite shielding layer through an extruder. The armor layer 6 is made by wrapping steel strips, steel wires, or galvanized steel wires around the inner sheath 5 to provide mechanical protection against compression, tension, and impact. The outer sheath 7 is extruded again using materials such as polyvinyl chloride, polyethylene, or polyurethane outside the armor layer 6 to form the outermost protective layer of the cable to resist external environmental corrosion, abrasion, and ultraviolet radiation.

[0045] This embodiment constructs an innovative buffer protection system by covering the outer layer of the cable core 1 with a support sheath 2 featuring corrugated protrusions 201 extending spirally along the axial direction, and filling the space between the inner wall of the support sheath 2 and the cable core 1 with a semi-conductive colloid 8. Compared with the prior art method of directly placing the shielding layer outside the cable core 1, the support sheath 2 and its corrugated structure in this embodiment can effectively disperse the load through the elastic deformation of the crests when the cable is subjected to radial impact, avoiding the impact force from being directly concentrated on the shielding layer. When the cable bends, the corrugated structure achieves buffering and energy absorption of bending stress through the increase of the trough spacing and the flattening of the crests, significantly reducing the fatigue damage to the shielding layer caused by bending. This design effectively isolates external mechanical stress from the sensitive composite shielding layer, thereby greatly improving the durability and anti-interference capability of the shielding layer. The filling of the semi-conductive colloid 8 not only improves the electric field distribution between the cable core 1 and the support sheath 2, reducing the risk of partial discharge, but also provides additional support and buffering for the support sheath 2, which, together with the corrugated structure, enhances the protection of the cable core 1 and the shielding layer. Thus, this embodiment, by introducing a support sheath 2 with a specific corrugated structure, combined with semi-conductive colloid filling 8 and a composite shielding layer, forms a multi-layered, synergistic protection system. This system effectively solves the technical problem of easy damage to the shielding layer of existing mining cables under complex mechanical stress, and significantly improves the anti-signal interference capability and service life of mining cables.

[0046] In this embodiment, the composite shielding layer includes an aluminum-plastic composite strip 3 and a tin-plated copper wire braided layer 4 arranged sequentially from the inside out. The aluminum-plastic composite strip 3 has a metallic aluminum foil side and is longitudinally fitted onto the support sleeve 2 with the metallic aluminum foil side facing the support sleeve 2. The tin-plated copper wire braided layer 4 is woven onto the outer surface of the aluminum-plastic composite strip 3. Specifically, the aluminum-plastic composite strip 3 is composed of a layer of aluminum foil and one or more layers of plastic film. The aluminum foil layer has good conductivity and shielding ability against high-frequency electromagnetic waves, while the plastic film provides insulation and mechanical support. The tin-plated copper wire braided layer 4 is a mesh structure formed by multiple strands of tin-plated copper wires in a cross-weaving manner. Tin plating can improve the oxidation resistance and conductivity of the copper wires, and the braided structure gives the shielding layer good flexibility and a comprehensive shielding effect against low-frequency magnetic fields and high-frequency electric fields. The metallic aluminum foil side is the aluminum foil layer with conductive shielding function in the aluminum-plastic composite strip 3. The aluminum-plastic composite strip 3 is longitudinally sleeved onto the support sleeve 2 with the aluminum foil side facing towards it. This ensures that the conductive surface of the aluminum foil is in close contact with the support sleeve 2, forming a continuous and effective electrical contact, which is crucial for shielding current conduction and attenuating high-frequency electromagnetic waves. The longitudinal sleeve method provides seamless shielding coverage, avoiding gaps that may be caused by spiral winding. The tin-plated copper wire braided layer 4 is woven onto the outer surface of the aluminum-plastic composite strip 3. This structure places the braided layer outside the aluminum-plastic composite strip 3, forming a double-layer composite shield. The braided layer not only provides additional mechanical protection but also enhances the shielding effect against low-frequency magnetic fields and high-frequency electric fields. Working synergistically with the aluminum-plastic composite strip 3, it improves the overall shielding performance.

[0047] In this embodiment, the aluminum foil surface of the aluminum-plastic composite tape 3 is pressed with periodic sinusoidal ripples. Specifically, the periodic sinusoidal ripples refer to a regular, repetitive, and approximately sinusoidal convex-concave structure formed on the aluminum foil surface of the aluminum-plastic composite tape 3 through processes such as pressing, rolling, or molding. This ripple structure extends periodically along the length of the aluminum-plastic composite tape 3. By pressing periodic sinusoidal ripples on the aluminum foil surface of the aluminum-plastic composite tape 3, the flexibility and ductility of the aluminum-plastic composite tape 3 are significantly improved. When the cable is bent or subjected to radial impact, the sinusoidal ripples can provide additional deformation space, allowing the aluminum-plastic composite tape 3 to better adapt to the surface deformation of the supporting sheath 2, thereby ensuring that the aluminum foil surface and the supporting sheath 2 always maintain a tight and uniform electrical contact, effectively enhancing the continuous conductivity of the composite shielding layer, and thus improving the overall signal shielding effect of the cable, especially under dynamic stress or bending conditions. In addition, the corrugated structure helps to disperse external stress and reduce the risk of fatigue damage or delamination caused by stress concentration in the aluminum-plastic composite tape 3, thereby improving the mechanical reliability and service life of the cable.

[0048] In this embodiment, cable core 1 is obtained through the following steps:

[0049] Multiple conductors are stranded into strands according to a concentric layer rule. Molten insulating material is uniformly extruded and wrapped around the conductors through an extruder to obtain insulated wire cores. The multiple insulated wire cores are then phase-shielded. The phase-shielded insulated wire cores are then stranded into a cable according to a layered arrangement rule and a set cable section diameter ratio, and a pad core is placed at the center of the stranding. The stranding process is SZ stranding.

[0050] Specifically, the conductor is typically made of copper or aluminum, which have good conductivity, and the insulation material is polyethylene (PE), cross-linked polyethylene (XLPE), or ethylene propylene rubber (EPR). The phase-separation shielding layer is made of semi-conductive or metallic materials. Its function is to further homogenize the electric field around the insulated cores, suppress electric field concentration, and effectively block electromagnetic crosstalk between cores. This is crucial for the signal integrity of mining cables in complex electromagnetic environments. As a preferred embodiment, each insulated core is wrapped with semi-conductive tape to achieve phase-separation insulation. The cable pitch ratio is a key parameter for measuring the tightness and flexibility of the cable core 1. A reasonable pitch ratio ensures that the cable core 1 maintains good flexibility while having sufficient mechanical stability. At the center of the stranding, a pad is placed. The pad is usually made of non-conductive filler material. Its main function is to fill the gaps inside the cable core 1, making the cable core 1 structure more rounded and compact, and providing uniform support for subsequent sheath extrusion, thereby improving the overall mechanical properties of the cable. In a preferred embodiment, the gaps between the insulated cores of each phase are filled with PP rope or PVC filler strips to maintain roundness, and polyester tape or non-woven fabric is wrapped around the multi-core cores to secure them and prevent loosening. Furthermore, the stranded cable employs an SZ stranding process. SZ stranding is a special stranding method characterized by the periodic alternation of the S and Z directions within each stranding pitch. This unique stranding structure endows the cable core 1 with superior flexibility and torsion resistance, significantly better than traditional unidirectional stranded cable core 1. By using the SZ stranding process to form the cable core 1, the flexibility and torsion resistance of the mining cable are effectively improved. SZ stranding makes the internal stress distribution of the cable core 1 more uniform when bent and under stress, significantly reducing the risk of displacement or damage to the core due to mechanical stress. This optimized cable core 1 structure, combined with phase shielding and padding, ensures that the cable maintains the stability and integrity of its internal structure even with frequent movement and bending in the complex and changing mining environment. This not only extends the service life of the cable, but also greatly ensures the stability of signal transmission by maintaining the spacing between the insulated cores and the effectiveness of the shielding layer, thereby effectively preventing external signal interference from affecting the quality of cable communication.

[0051] In the production process of mining cables, precise control of the extrusion temperature of the inner sheath 5 and outer sheath 7 is crucial to the performance and quality of the cable. The effectiveness of extrusion temperature control indirectly and significantly affects the shielding effect of the cable. In this embodiment, the extrusion temperature of the sheath is controlled by the following method:

[0052] Real-time temperature during the extrusion process of mining cable sheaths Calculate its deviation from the set target temperature. ;

[0053] Based on asymmetric hysteresis interval and and continuous over-limit counters, when When entering a certain range, the system state does not switch immediately, but first determines the state of the deviation to obtain the current operating state;

[0054] When the current operating state is over-limit correction, the set target temperature for the next cycle is smoothly corrected based on the preset correction step size, and control commands are output to the extruder heating module.

[0055] In this embodiment, the update process of the continuous over-limit counter satisfies the following formula:

[0056] ;

[0057] in, For the continuous out-of-bounds counter in the nth sampling period, This is the maximum value of the counter. The deviation between the real-time temperature and the set target temperature in the nth sampling period is denoted as _____. θ n This refers to the real-time temperature at the corresponding moment during the extrusion process; This is the lower inner threshold of the outer hysteresis window. The attenuation coefficient is... , This is an indicator function. Specifically, it first records the number of consecutive "deviation out of bounds" occurrences. ,like Exceeding the inner layer threshold (Low temperature side) or (High-temperature side), then ;like If it falls back to the non-critical region, then Attenuation to Only when Reaching the preset confirmation threshold Only then does the system determine "steady-state overshoot" and trigger a fixed increment. (or The set value is added to the next cycle. This allows for a smooth correction of the overall temperature. In this embodiment, by limiting the maximum value of the counter, the infinite accumulation of the counter value under extreme or prolonged deviations can be effectively prevented, thus avoiding oscillations or instability in the control system due to over-response. This ensures the robustness and safety of the control strategy. The indicator function is a binary function that expresses the absolute value e of the deviation between the real-time temperature and the set target temperature. n The lower limit threshold H of the outer hysteresis window is greater than the inner limit threshold. down When the deviation exceeds a preset significant threshold, its value is 1; otherwise, its value is 0. The indicator function precisely controls the accumulation condition of the continuous over-limit counter. The counter is only triggered to increase when the deviation truly exceeds the preset significant threshold, thus avoiding counting normal fluctuations. The decay coefficient introduces a "forgetting" mechanism, causing the value of the continuous over-limit counter to decay exponentially when no new over-limit events occur. For example, when λ is close to 1, the decay rate is fast, and the counter is more sensitive to recent events; when λ is close to 0, the decay rate is slow, and the counter has a longer memory effect. This ensures that the counter can reflect the "freshness" of the deviation, avoiding the long-term inappropriate influence of historical deviations on current control decisions. Through this formula, the update process of the continuous over-limit counter is precisely defined, enabling it to dynamically reflect the persistence and severity of temperature deviations. The introduction of the decay coefficient λ allows the counter to decay gradually when there is no continuous over-limit, avoiding over-correction caused by the counter value remaining high for a long time, thereby improving the system's response sensitivity and stability. Simultaneously, the maximum value X of the counter... max Its upper limit is limited to prevent control system instability that might be caused by the counter growing indefinitely. Indication function 1 {|e_n |>H_down} Ensure that only when the deviation exceeds the preset threshold H down The counter is incremented only at specific times, effectively filtering out minor fluctuations and allowing the system to focus on handling truly critical anomalies. This update mechanism enables the temperature control system to more intelligently determine its current operating status, avoiding frequent or unnecessary corrections. This ensures temperature stability and product quality during the extrusion process of mining cable sheaths, and reduces the scrap rate.

[0058] In this embodiment, the state determination is based on the following formula:

[0059]

[0060] in, This represents the current operating state corresponding to the nth sampling period. This represents the deviation between the real-time temperature and the set target temperature corresponding to the nth sampling period. This is the lower inner threshold of the outer hysteresis window. The upper limit threshold of the outer hysteresis window. For the continuous out-of-bounds counter in the nth sampling period, To confirm the threshold.

[0061] Specifically, this state determination formula defines three operating states of the temperature control system during the sheath extrusion process. First, when the deviation e between the real-time temperature of the nth sampling cycle and the set target temperature... n The absolute value is less than or equal to the inner lower limit threshold H of the outer hysteresis window. down And the continuously exceeding counter x n When the value is 0, the system is considered to be in a "normal" state, indicating that the current temperature fluctuation is within an acceptable range and there are no persistent abnormalities; therefore, the system does not require correction. Secondly, when the deviation e... n The absolute value is greater than H down But less than H up And the continuously exceeding counter x n Less than the confirmation threshold X TM When the temperature begins to deviate to a certain extent, but not to the point where immediate correction is needed, or the duration of the deviation is insufficient to trigger correction, the system will continue monitoring. Finally, when the deviation e... n The absolute value is greater than or equal to H up When, or when the deviation e n The absolute value is between H down and H up Between but continuously exceeding the limit counter x n Greater than or equal to the confirmation threshold X TM When the temperature deviation reaches a point where it needs immediate correction, whether it's a sudden, large deviation or a sustained, moderate deviation, the system will trigger a subsequent temperature correction mechanism. The introduction of this state determination formula provides a clear, accurate, and robust operating status identification mechanism for the temperature control system in the extrusion process of mining cable sheaths. This mechanism comprehensively considers the real-time temperature deviation e. n Instantaneous size and continuous over-limit counter x n The persistence of the reflected deviation, combined with the preset threshold H down H up and X TM The system can intelligently distinguish between three operating conditions: "normal," "critical," and "over-limit correction." When the temperature deviation is small and not sustained, the system is classified as "normal," avoiding unnecessary correction actions and thus reducing disturbances to the control system. When the temperature deviation is within a moderate range but has not persisted for a sufficiently long time, the system is classified as "critical," allowing for the observation of potential problems and preventing overreaction to transient noise or minor fluctuations. More importantly, when the temperature deviation reaches a large level (|e n |≥Hup (H) or moderate deviation lasting for a longer period of time down <|e n | <H up And x n ≥X TM When a temperature deviation is detected, the system can quickly and accurately determine that it is in an "over-limit correction" state and promptly initiate temperature correction to ensure a rapid response to severe or persistent temperature deviations. This refined state determination avoids misjudgments or delayed corrections that may occur in traditional control methods, significantly improving the accuracy and stability of sheath extrusion temperature control. This, in turn, helps to improve the overall quality of mining cable sheaths, reduce the scrap rate during production, and optimize production efficiency.

[0062] In this embodiment, the smooth correction of the target temperature for the next cycle based on a preset correction step size is achieved through the following formula:

[0063] ;

[0064] in, The target temperature is set for the (n+1)th sampling period. The constant target temperature set at the beginning of the process. For single correction step size, The deviation between the real-time temperature and the set target temperature in the nth sampling period. For symbolic functions, This is an indicator function.

[0065] Specifically, the formula defines how to obtain the set target temperature for the next sampling period under specific conditions. This is not simply pulling the real-time temperature back to a fixed value, but rather based on an initially set constant target temperature θ. set,0 Combined with the current temperature deviation e n The system adjusts the temperature in a conditional and directional manner according to the direction and preset correction step size Δθ. This adjustment mechanism ensures that temperature adjustment is only performed when the system is determined to require "over-limit correction," and the direction of adjustment is consistent with the direction of temperature deviation, thereby avoiding unnecessary or reverse corrections and improving control accuracy and responsiveness. Wherein, θ set,n+1 The temperature value that the control system expects the extruder heating module to reach in the next control cycle is used as the new control target. θ set,0 This is a reference temperature value pre-set at the beginning of the entire extrusion process based on the cable material properties and process requirements, providing a stable reference point for temperature correction. Δθ is the set range of target temperature change for each temperature correction; this step size is preset and can be adjusted according to specific process requirements, material properties, and system response speed. nThis represents the difference between the currently measured extrusion temperature and the currently set target temperature. Its positive or negative sign indicates whether the real-time temperature is higher or lower than the set target temperature, and its absolute value indicates the magnitude of the deviation. It serves as the direct basis for temperature correction. n ) is a mathematical function used to determine e n The sign of the value ensures that the correction direction is consistent with the temperature deviation direction; that is, when the temperature is too high, the target temperature is lowered, and when the temperature is too low, the target temperature is raised. {状态n="超限修正"} It is a Boolean function that, when the condition `state` is met, returns a value. n When "over-limit correction" is true, its value is 1; otherwise, its value is 0. This indicator function is key to implementing conditional correction. It ensures that temperature correction is triggered only when the system is determined to be in an "over-limit correction" state, thus avoiding unnecessary corrections in normal or critical states and improving the stability of the control system. This embodiment, by introducing the aforementioned temperature correction formula, enables the temperature control system to smoothly and directionally adjust the target temperature for the next cycle based on a clear correction formula when determining the current operating state as "over-limit correction" during the extrusion process of mining cable sheaths, according to real-time temperature deviation, asymmetric hysteresis interval, and continuous over-limit counter. n This ensured that the correction direction was consistent with the temperature deviation e. n The direction is consistent: if the temperature is too high, the target temperature will be lowered; if the temperature is too low, the target temperature will be raised. Simultaneously, indicator function 1... {状态n="超限修正"} This ensures that adjustments are only made when truly necessary, avoiding erroneous operations under normal or critical conditions. This is based on an initial constant target temperature θ. set,0 The correction mechanism with a preset correction step size Δθ enables the temperature adjustment process to respond quickly to over-limit situations while maintaining smoothness, effectively avoiding temperature oscillations, overshoot, or correction lag problems that may occur with traditional fixed step size or simple proportional control. Ultimately, this helps to achieve precise and stable control of the sheath extrusion temperature, thereby improving the quality and production efficiency of cable sheaths and reducing scrap rates. It should be noted that the control and correction of the extrusion temperature in this embodiment can be achieved using an existing controller with a preset control program. For example, a computer program for executing this control method can be stored in the computer's memory. The real-time temperature of the sheath is collected by a temperature sensor and transmitted back to the computer's processor. The computer's processor receives the set variable values ​​and executes the aforementioned program to implement the method in this embodiment, outputting the corrected target temperature control command to the extruder actuator. This is an application of existing technology and will not be elaborated further.

[0066] In this embodiment, the support sheath 2 is made of a semi-conductive elastomer material. Multiple corrugated protrusions 201 are evenly distributed circumferentially on the outer wall of the support sheath 2. The pitch of the corrugated protrusions 201 on the outer wall of the support sheath 2 is inversely proportional to the cable core 1's pitch ratio. The elastomer material ensures that when the support sheath 2 is subjected to radial impact or bending, its corrugated protrusions 201 can effectively undergo elastic deformation, thereby dispersing the load and absorbing energy. After the load is released, it returns to its original shape, ensuring the cable's mechanical protection performance. The semi-conductivity helps to homogenize the electric field distribution, reduce local electric field strength, and effectively suppress partial discharge, thereby improving the cable's electrical performance and anti-signal interference capability. This material is typically prepared by incorporating an appropriate amount of conductive filler (e.g., carbon black, graphite) into an elastic polymer matrix (e.g., ethylene propylene rubber, silicone rubber, etc.). Its resistivity is usually controlled within a specific range to achieve semi-conductive properties. The circumferentially distributed design of multiple protrusions allows the impact force to be more evenly distributed across the entire circumferential structure of the support sheath 2 when the cable is subjected to radial impact, avoiding excessive stress at single points or in localized areas. Simultaneously, the multiple corrugated protrusions 201 provide more deformation paths and larger buffer space, further enhancing the impact resistance and energy absorption capacity of the support sheath 2, and improving the overall mechanical strength and durability of the cable. The pitch of the corrugated protrusions 201 on the outer wall of the support sheath 2 is designed to be inversely proportional to the cable core 1's pitch ratio, ensuring that the support sheath 2 can better follow the deformation of the cable core 1 when the cable bends, reducing internal friction and stress concentration, thereby effectively protecting the cable core 1 and its shielding layer, and maintaining the stability of the cable's signal transmission.

[0067] In this embodiment, the braiding density of the tinned copper wire braided layer 4 is not less than 85%. Braiding density refers to the percentage of the area covered by the conductors in the braided layer relative to the total area, and is a key parameter for measuring the shielding effect of the braided shielding layer. Higher braiding density results in smaller mesh sizes, stronger blocking ability against electromagnetic waves, and better shielding performance. The braiding density of the tinned copper wire braided layer 4 is limited to not less than 85%. Braided layers with densities lower than this may not provide sufficient shielding attenuation, while excessively high densities may increase production costs and cable flexibility. Therefore, a braiding density of not less than 85% aims to ensure a balance between cost and performance, providing reliable electromagnetic shielding for mining cables, and is preferably 90%-95%.

[0068] Thus, this embodiment improves the cable's protective performance and resistance to bending and impact by adding a support sheath 2 and dynamically controlling the extrusion temperature of the inner and outer sheaths 7, effectively enhancing its anti-interference capability.

[0069] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0070] The above descriptions are merely embodiments of the present invention. Commonly known structures and characteristics of the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A manufacturing process for anti-signal interference mining cables, characterized in that, Includes the following steps: Obtain the cable core after cabling; A support sleeve is fitted over the outer layer of the cable core, and a semi-conductive colloid is filled between the inner wall of the support sleeve and the cable core. A composite shielding layer is fabricated on the outside of the support sleeve, so that the outer wall of the support sleeve is in contact with the inner surface of the composite shielding layer; The inner sheath extrusion, armor layer setting, and outer sheath extrusion are performed sequentially outside the composite shielding layer. The outer wall of the support sheath is provided with corrugated protrusions that extend spirally along the axial direction; the radial height difference between the crests and troughs of the corrugated protrusions is 5%-10% of the cable core diameter.

2. The manufacturing process for anti-signal interference mining cables according to claim 1, characterized in that: The composite shielding layer includes an aluminum-plastic composite strip and a tin-plated copper wire braided layer arranged sequentially from the inside to the outside. The aluminum-plastic composite strip has a metal aluminum foil side and is longitudinally wrapped around the support sleeve with the metal aluminum foil side facing the support sleeve. The tin-plated copper wire braided layer is woven on the outer surface of the aluminum-plastic composite strip.

3. The manufacturing process for anti-signal interference mining cables according to claim 2, characterized in that: The aluminum foil surface of the aluminum-plastic composite strip is pressed with sinusoidal ripples.

4. The manufacturing process for anti-signal interference mining cables according to claim 3, characterized in that: The cable core is obtained by the following steps: Multiple conductors are twisted together in a concentric layer pattern, and molten insulating material is uniformly extruded and wrapped around the conductors through an extruder to obtain an insulated wire core. Multiple insulated wire cores are shielded by phase; After phase shielding, the insulated wire cores are stranded into a cable according to the layer arrangement rules and the set cable section diameter ratio, and a pad core is placed at the center of the stranding. The stranded cable is manufactured using the SZ stranding process.

5. The manufacturing process for anti-signal interference mining cables according to claim 1, characterized in that: The extrusion temperature of the sheath is controlled by the following methods: Collect the real-time temperature during the extrusion process of mining cable sheaths and calculate its deviation from the set target temperature; Based on the asymmetric hysteresis interval and the continuous over-limit counter, the deviation is determined to obtain the current operating state; When the current operating state is over-limit correction, the set target temperature for the next cycle is smoothly corrected based on the preset correction step size, and control commands are output to the extruder heating module.

6. The manufacturing process for anti-signal interference mining cables according to claim 5, characterized in that: The update process of the continuous over-limit counter satisfies the following formula: ； in, For the continuous out-of-bounds counter in the nth sampling period, This is the maximum value of the counter. The deviation between the real-time temperature and the set target temperature in the nth sampling period. This is the lower inner threshold of the outer hysteresis window. The attenuation coefficient is... , This is an indicator function.

7. The manufacturing process for anti-signal interference mining cables according to claim 6, characterized in that: The state determination is based on the following formula: The update process of the over-limit counter satisfies the following formula: in, This represents the current operating state corresponding to the nth sampling period. This represents the deviation between the real-time temperature and the set target temperature corresponding to the nth sampling period. This is the lower inner threshold of the outer hysteresis window. The upper limit threshold of the outer hysteresis window. For the continuous out-of-bounds counter in the nth sampling period, To confirm the threshold.

8. The manufacturing process for anti-signal interference mining cables according to claim 7, characterized in that: The smooth correction of the target temperature for the next cycle based on a preset correction step size is achieved through the following formula: ； in, The target temperature is set for the (n+1)th sampling period. The constant target temperature set at the beginning of the process. For single correction step size, The deviation between the real-time temperature and the set target temperature in the nth sampling period. For symbolic functions, This is an indicator function.

9. The manufacturing process for anti-signal interference mining cables according to claim 4, characterized in that: The support sheath is made of a semi-conductive elastomer material, and multiple corrugated protrusions are evenly distributed circumferentially on the outer wall surface of the support sheath. The pitch of the corrugated protrusions on the outer wall surface of the support sheath is inversely proportional to the cable core pitch ratio.

10. The manufacturing process for anti-signal interference mining cables according to claim 4, characterized in that: The braiding density of the tin-plated copper wire braided layer is not less than 85%.

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