A kind of distribution network 10kV cable main insulation layer reaction force cone processing technology and cutting device

Abstract

The present application relates to the technical field of high-voltage cable manufacturing, and discloses a distribution network 10kV cable main insulation layer reaction force cone processing technology and cutting device. The technology comprises the following processing steps: equipment point inspection, cable sheath stripping, copper shield and semi-conductive layer stripping, fixing stress tube, cutting reaction force cone, crimping connecting tube, wrapping semi-conductive tape and filling glue, fixing insulation tube, installing shielding net and ground wire, fixing sheath, and power transmission operation acceptance. In the step of cutting reaction force cone, the starting position of cable cutting is optimized, the length of reaction force cone is determined, the cutting diameter and its design requirements are determined, the number of cutting tools used by the forming device is determined, and the cutting speed is determined. The present application can be applied to the cutting of reaction force cones of different specifications of 10kV cables, ensures that the cutting process of reaction force cones is quickly and efficiently completed during construction, effectively avoids problems caused by differences in technical experience of workers, differences in work tools, and the like, and ensures good quality of reaction force cones.

Description

Technical Field

[0001] This invention relates to a process and cutting device for treating the reactive force cone of the main insulation layer of a 10kV distribution cable, belonging to the field of high-voltage cable manufacturing technology. Background Technology

[0002] As society's reliance on electricity continues to increase and the need for urban beautification grows, the cable coverage rate in urban areas is rising year by year, accompanied by a gradual increase in the difficulty of cable operation. The 10kV medium-voltage distribution network is the most common and widely used distribution network system. Due to limitations in high-voltage cable manufacturing processes, the maximum length that can be manufactured without joints is 10km. Therefore, it is necessary to process individual cable joints and splice multiple cables together to achieve ultra-long-distance transmission.

[0003] At cable splices, the electric field distribution differs from that of the cable body insulation and the additional insulation due to the presence of two different insulating materials. This creates a potential difference, or axial field strength, between adjacent points on the same layer of insulation. The insulation near the conductor connection end is cut into a conical surface, known as a reactive force cone, and then additional insulation is wrapped around it, forming stress cone surfaces at both ends. This alters the potential distribution on the insulation surface, achieving a uniform electric field and ensuring joint safety.

[0004] For stress cones, prefabrication is now commonly used. Cable manufacturers in Europe and America, such as Brugg (Switzerland), Pirelli (Italy), and Nexan (France), as well as companies like Shenyang Cable Factory and Shanghai Sanyuan Cable Accessories Company in my country, all produce products with this structure. Reaction cones, however, can only be made by machining the main insulation of the cable. Since the theoretical curve is the ratio of two logarithmic functions, to simplify the construction process, reaction cones are generally made with a straight conical surface. Currently, the machining of this conical surface in my country mainly involves manual cutting with a knife or glass plate, followed by sanding. This machining method is laborious and time-consuming, and cannot guarantee quality, making it difficult to meet technical standards during construction.

[0005] Therefore, in order to ensure the safety of high-voltage cables, it is urgent to design a simple, efficient, and high-quality reactive cone treatment process and cutting device for the main insulation layer of 10kV distribution network cables. Summary of the Invention

[0006] In order to solve the above-mentioned problems in the existing technology, the present invention provides a process for treating the reactive force cone of the main insulation layer of 10kV distribution network cables.

[0007] The technical solution of the present invention is as follows:

[0008] A process for treating the reactive force cone of the main insulation layer of a 10kV distribution cable includes the following steps:

[0009] Equipment component inspection, cable sheath removal, copper shielding and semi-conductive conductive layer removal, stress tube fixing, reactive force cone cutting, connecting pipe crimping, semi-conductive tape wrapping and filler adhesive wrapping, insulating pipe fixing, shielding mesh and grounding wire installation, sheath fixing, power-on operation and acceptance.

[0010] The cutting reaction force cone step specifically includes the following processing steps:

[0011] Step a: Determine the starting position for cable cutting;

[0012] Step b: Determine the length of the reactive force cone;

[0013] Step c: Determine the cutting diameter and its design requirements;

[0014] Step d: Determine the number of cutting tools to be used in the forming device;

[0015] Step e: Determine the cutting speed.

[0016] In step a, according to the provisions on connecting pipes in GB 14315-93 "Crimped Copper and Aluminum Terminals and Connecting Pipes for Conductors of Power Cables", the material and length of the connecting pipe are determined in combination with the cross-sectional area and material of the cable core, and then the starting position of the reaction force cone cutting is determined.

[0017] In step b, the length L of the stress cone surface c The shape is designed such that the axial field strength on its surface is equal to or less than the maximum allowable axial field strength.

[0018] Reaction cone length L c It can be calculated using the following formula:

[0019] L c =UIn(r i / r c ) / E t In(r n / r c )

[0020] In the formula: r i —Cable insulation radius

[0021] r n —Increase the radius of the insulation winding

[0022] r c — Core radius

[0023] In the formula, U is the design voltage of the cable joint, which is 1.1 times the power frequency test voltage. Referring to the American IEEE standard, when U is the design voltage, for self-adhesive cable joints, E is taken as... t =0.3~1KV / mm.

[0024] In step c, the insulation layer thickness of the 10KV cable is consistently 4.5mm. The shape of the cutting tool in the forming device does not need to be changed, but the position of the cutting tool needs to be adjustable to accommodate cables of different specifications.

[0025] In step d, three sets of tools are used to cut simultaneously by turning, and the tools are designed with complex logarithmic curves.

[0026] In step e, the factors to be considered in determining the cutting speed include the main insulation material of the cable, the heat generated during the cutting process of the tool, and the overall dynamic balance of the cutting device.

[0027] A reaction force cone cutting device for the main insulation layer of a kV distribution cable includes an annular outer shell. A rotating ring is embedded and rotatably mounted on the inner ring of the annular outer shell. A driving device for driving the rotating ring to rotate is provided on one outer side of the annular outer shell. Several mounting plates are arranged in a ring on the inner ring of the rotating ring. Each mounting plate is equipped with a tool holder, wherein the cutting edge profile of the tool is consistent with the arc-shaped profile of the reaction force cone surface as described in any one of the claims. The tool holder can move radially relative to the mounting plate along the rotating ring. The device also includes an adjustable pitch annular disk assembly. Several arc-shaped grooves corresponding to each tool holder are arranged in a ring on the disk surface of the adjustable pitch annular disk assembly. The distance between each point on the arc-shaped groove and the center of the adjustable pitch annular disk assembly gradually increases / decreases. The tool holder is provided with a sliding pin embedded in and slidably connected to the arc-shaped groove. The rotation of the adjustable pitch annular disk assembly can synchronously drive each tool holder to converge or disperse towards the center of the rotating ring.

[0028] The driving device includes a drive motor, a drive gear is installed at the output end of the drive motor, and an external gear ring that meshes with the drive gear is provided on the outer periphery of the rotating ring.

[0029] The adjustable annular disk assembly includes two parallel annular disks spaced apart, which are fixedly connected by several connecting columns. The rotating ring is sandwiched between the two annular disks and is rotatably installed.

[0030] In one of the annular disks, a conical external toothed ring is provided on the outer edge of the outer disk surface. A fixing plate is provided on the outer wall of the annular shell corresponding to the conical external toothed ring. An adjusting shaft is rotatably mounted on the fixing plate. A bevel gear that meshes with the conical external toothed ring is installed on one end of the adjusting shaft, and a hand-tightening handle is provided on the other end. A positioning nut is screwed onto the adjusting shaft. After the positioning nut is tightened, it abuts against the fixing plate to restrict the rotation of the adjusting shaft.

[0031] The present invention has the following beneficial effects:

[0032] The reaction cone treatment process for the main insulation layer of 10kV distribution network cables of this invention can be applied to the cutting of reaction cones of different specifications of 10kV cables, ensuring that the reaction cone cutting process is completed quickly and efficiently during construction. Furthermore, it can be extended to the cutting of reaction cones of other cables of different voltage levels, effectively avoiding problems caused by differences in the technical experience of operators and differences in operating tools, and ensuring good quality of reaction cones.

[0033] This invention relates to a process for treating the reactive force cone of the main insulation layer of 10kV distribution cables. The shape of the reactive force cone is determined based on the tangential field strength along this surface in the cable, taking into account operating voltage, structural dimensions, insulation thickness, and material properties, resulting in a cone surface curve. Furthermore, the surface parameters are optimized based on actual construction conditions to achieve an ideal surface for the reactive force cone.

[0034] This invention relates to a reaction cone cutting device for the main insulation layer of 10kV distribution network cables. It includes three rotatable cutting tools driven by a motor. The spacing between the tools can be synchronously adjusted by using an adjustable annular disc assembly with an arc groove and a sliding pin. This ensures that the processing center of each tool corresponds to the center of the cable with different wire diameters. As a result, this device can not only process cables of different wire diameters, but also ensure the coaxiality between the reaction cone surface and the mandrel after cable processing. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the process of stripping the cable sheath according to the present invention;

[0036] Figure 2 This is a schematic diagram of the present invention involving the removal of the shielding layer and the semiconductive layer;

[0037] Figure 3 This is a schematic diagram of the fixed stress tube of the present invention;

[0038] Figure 4 This is a schematic diagram showing the installation of the shielding mesh and grounding wire for this invention;

[0039] Figure 5 This is a schematic diagram of the cable sheath installation according to the present invention;

[0040] Figure 6 This is a cross-sectional view of the main insulation portion of the 10kV cable of the present invention;

[0041] Figure 7 This is a comparison table of cross-linked cable insulation thickness according to the present invention;

[0042] Figure 8 This is a schematic diagram of the copper or aluminum connecting pipe of the present invention;

[0043] Figure 9 The dimensions of the copper connecting pipe (GT type) of this invention;

[0044] Figure 10 The dimensions of the aluminum connecting tube (GT type) of this invention;

[0045] Figure 11 This is a schematic diagram of the cable structure of the present invention;

[0046] Figure 12 This is a schematic diagram of the overall structure of the cutting device of the present invention;

[0047] Figure 13 This is a schematic diagram of the rotating ring structure of the cutting device of the present invention;

[0048] Figure 14 This is a schematic diagram of the tool holder structure of the cutting device of the present invention;

[0049] Figure 15 This is a schematic diagram of the adjustable annular disk assembly structure of the cutting device of the present invention;

[0050] Figure 16 for Figure 15 A schematic diagram of the structure at point A in the diagram. Detailed Implementation

[0051] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0052] Example 1

[0053] See Figure 1-6 A process for treating the reactive force cone of the main insulation layer of a 10kV distribution cable includes the following steps:

[0054] Equipment component inspection, cable sheath removal, copper shielding and semi-conductive conductive layer removal, stress tube fixing, reactive force cone cutting, connecting pipe crimping, semi-conductive tape wrapping and filler adhesive wrapping, insulating pipe fixing, shielding mesh and grounding wire installation, sheath fixing, power-on operation and acceptance.

[0055] Specifically,

[0056] 1) Equipment component inspection:

[0057] Open the box and check whether the quantity of the items matches the packing list and whether there are any abnormalities in appearance.

[0058] 2) Remove the cable sheath ( Figure 1 ):

[0059] Straighten the cable: After leaving appropriate slack, lay the cable flat. Straighten and clean the two cables to be connected within two meters of each other, overlap them by 200mm, and mark the center line in the middle as the center of the joint.

[0060] Stripping the outer sheath and armor: Starting from the center mark, measure 800mm and 500mm on each of the two cables respectively, and strip the outer sheath; bind the armor 50mm from the break with copper wire three times or use armor tape to secure it, and use a hacksaw to cut a ring mark along the copper wire binding or the edge of the clip, with a depth of 1 / 2 the thickness of the steel tape. Then use a screwdriver to pry up the tip of the steel tape, and then use wire cutters to clamp and remove the steel tape.

[0061] Peel off the inner protective layer: Measure 20mm of the inner protective layer from the armor break, peel off the remaining inner protective layer, and remove the filler.

[0062] Cut the core wire, align the core wire, and cut it at the center point.

[0063] 3) Remove the shielding layer and semiconductive layer ( Figure 2 ):

[0064] Remove the shielding layer 300mm from the center point towards each end of the core wire. Measure 20mm of the semiconductive layer from the cut in the shielding layer, and remove the rest. Thoroughly remove the semiconductive material from the surface of the insulator.

[0065] 4) Fixed stress tube ( Figure 3 ):

[0066] Stress tubes are inserted into each phase on both sides of the center, with a 20mm overlap of the copper shielding layer, and then heated and shrunk for fixation. The tubes are then inserted, and sealing sleeves and sheaths are inserted into the side where the cable sheath has been stripped longer; sealing sleeves are inserted into the side where the sheath has been stripped shorter; inner and outer insulating tubes, semi-conductive tubes, and copper mesh are inserted into each phase core wire.

[0067] When using heat to shrink and fix heat-shrinkable materials, the following should be noted:

[0068] The heat shrinkage temperature is 110℃~120℃. Therefore, adjust the torch flame to a soft yellow flame and avoid a high-temperature blue flame to prevent burning the heat shrinkable material.

[0069] When you start heating the material, the flame should slowly approach the material, move around the material to heat it evenly, and keep the flame moving in the forward (contracting) direction to preheat the material.

[0070] The flame should advance in a spiral motion to ensure that the insulating tube contracts fully and evenly in all directions.

[0071] 5) Cutting reaction force cone:

[0072] Measure half the length of the connecting tube plus 5mm from the end of the core wire and cut off the core insulation. Measure 35mm from the cut end of the core insulation and cut it into a 30mm long cone.

[0073] 6) Crimped connecting pipes:

[0074] Use a crimping tool to crimp the connecting tube onto the cable core to connect the two cables.

[0075] 7) Wrapping the semiconductor tape and filler adhesive:

[0076] Remove any sharp edges and burrs from the connecting tube with fine sandpaper and clean it thoroughly. Then, wrap a semiconductive tape around the connecting tube, overlapping it with the semiconductive layers at both ends. Wrap a filler adhesive between the cones at both ends with a thickness of not less than 3 mm.

[0077] 8) Fix the insulating tube:

[0078] Fixing the inner insulation tube: Pull the inner insulation tube of the three-green fertilizer from the cable end and place it between the stress tubes at both ends. Heat and shrink it from the middle towards both ends to fix it. The heating flame should be directed in the direction of shrinkage.

[0079] Secure the outer insulating tube: Place the outer insulating tube over the center of the inner insulating tube. Heat and shrink the tube from the center outwards to secure it.

[0080] Fixing the semiconductive tubes: Place two semiconductive tubes on the insulating tube in sequence, cover each end with a 50mm copper shielding layer, and then heat and shrink them from both ends toward the middle to fix them.

[0081] 9) Install shielding mesh and grounding wire ( Figure 4 ):

[0082] Pull out the shielding mesh from one end of the cable core wire, connect the two ends of the copper shielding layer, bind the ends with copper wire, and solder them firmly. Wrap the ground wire tightly around the core wire, bind and solder the two ends of the core wire to the armor with copper wire, and solder them firmly to the shielding layers on both sides.

[0083] 10) Fixing sleeve ( Figure 5 ):

[0084] Connect the two halves of the sheet metal sheath together with a snap-fit, secure them at both ends with wire, and remove any burrs from the sheet metal with a file. Slide the sheath sleeve over the cable, placing the sealing sleeves over the sheath heads at both ends, overlapping the sheath sleeve and the outer cable sheath by 100mm at each end. Heat and shrink to secure.

[0085] 11) Acceptance of power-on operation:

[0086] After the cable joint is fabricated, it shall be tested by the testing department as required.

[0087] After passing the test, the system was powered on and operated under no-load for 24 hours without any abnormalities. Acceptance procedures were then completed, and the system was handed over to the construction unit for use. Simultaneously, technical documents such as change orders, product certificates, test reports, and operation records were submitted.

[0088] A cross-sectional view of the main insulation of a 10kV cable is shown below. Figure 6As shown, the cable includes a main insulation layer, a cable conductor portion, and a portion of the main insulation material to be removed. There is a very thin inner semiconductive layer between the cable conductor and the main insulation layer. The reactive force cone of the cable main insulation refers to the standard complex logarithmic surface after removing the portion of the main insulation material to be removed. The starting point for material removal is A, the ending point is B, the diameter of the main insulation layer is D, and the diameter of the cable conductor portion is d.

[0089] Example 2

[0090] The insulation layer, also known as the main insulation, has the specific function of withstanding system voltage. Throughout the cable's service life, it must withstand the rated voltage, overvoltages from system faults, and lightning impulse voltages, ensuring that no phase-to-ground or phase-to-phase breakdown short circuits occur under operating heating conditions. Therefore, the main insulation material is crucial to the quality of the cable.

[0091] Cross-linked polyethylene (XLPE) is an excellent insulating material that is now widely used and is the mainstream material for the main insulation of 10kV cables. It is bluish-white and semi-transparent. Its characteristics include: high insulation resistance; ability to withstand high power frequency and pulse electric field breakdown strength; low dielectric loss tangent; chemical stability; good heat resistance, with a long-term allowable operating temperature of 90℃; good mechanical properties; and ease of processing and handling.

[0092] Cross-linked polyethylene (XLPE) insulated cables utilize a peroxide cross-linking method, transforming the linear molecular structure of polyethylene into a three-dimensional network structure, and changing it from a thermoplastic to a thermosetting material. This increases the operating temperature from 70℃ to 90℃, significantly improving the cable's current-carrying capacity. XLPE insulated cables offer the following advantages:

[0093] 1. Heat resistance: The three-dimensional mesh structure of XLPE has excellent heat resistance. It will not decompose or carbonize below 300℃, the long-term working temperature can reach 90℃, and the thermal life can reach 40 years.

[0094] 2. Insulation performance: XLPE retains the good insulation properties of PE, and the insulation resistance is further increased. Its dielectric loss tangent is very small and is not significantly affected by temperature.

[0095] 3. Mechanical properties: Due to the formation of new chemical bonds between macromolecules, the hardness, stiffness, wear resistance and impact resistance of XLPE are improved, thus making up for the shortcomings of PE being susceptible to cracking due to environmental stress.

[0096] 4. Chemical resistance: XLPE has strong resistance to acids, alkalis and oils. Its combustion products are mainly water and carbon dioxide, which have little harm to the environment and meet the requirements of modern fire safety.

[0097] Halogen-free, low-smoke, flame-retardant cross-linked polyethylene insulated cables have excellent flame-retardant properties. The sheath material is halogen-free, ensuring that only a small amount of toxic and corrosive gases are released during combustion. They produce less smoke and are an environmentally friendly new product. They also have superior electrical properties, heat resistance, chemical resistance, environmental stress cracking resistance, and aging resistance, and have a long service life.

[0098] By consulting the cross-linked cable insulation thickness comparison table, we can obtain... Figure 7 The table shown below;

[0099] Depend on Figure 7 As shown in the table, the nominal insulation thickness of the different 10KV cables is 4.5mm, which is consistent and provides convenience for the design of subsequent automation equipment.

[0100] Example 3

[0101] Step a: Determining the starting position for cable cutting;

[0102] In cable joints, to effectively control the axial field strength at the end of the cable insulation, the insulation end is shaped into a conical surface that runs in the opposite direction to the stress cone surface; this is called the reaction cone. The reaction cone is the interface between the filler insulation and the cable insulation in the joint. This interface is the weak point of the cable joint. If it is not handled properly during design or installation, slippage and breakdown along the surface of the reaction cone can easily occur.

[0103] As can be seen from the cutting reaction cone process, the starting position of the reaction cone cutting is related to the length of the connecting tube at the end of the core wire.

[0104] Find GB 14315-93 for crimped copper and aluminum terminals and connecting pipes for conductors of power cables, which is applicable to power cables of 35KV and below.

[0105] Copper or aluminum connecting pipes (GT type or GL type) are shaped as follows Figure 8 :

[0106] Figure 9 The dimensions of the copper connecting pipe (GT type) are shown below;

[0107] Figure 10 The dimensions of the aluminum connecting pipe (GT type) are shown below;

[0108] The starting position of the reactive cone cutting can be calculated based on the material and length of the connecting pipe in the table above.

[0109] Step b: Determine the length of the reactive force cone;

[0110] After determining the starting position of the cut, the next step is to determine the length of the cut. The length L of the stress cone surface... cThe shape is designed such that the axial field strength on its surface is equal to or less than the maximum permissible axial field strength.

[0111] The length of the reactive force cone can be calculated using the following formula:

[0112] L c =UIn(r i / r c ) / E t In(r n / r c )

[0113] In the formula: r i —Cable insulation radius

[0114] r n —Increase the radius of the insulation winding

[0115] r c — Core radius

[0116] In the formula, U is the design voltage of the cable joint, which is 1.1 times the power frequency test voltage, referring to the American IEEE standard; when U is the design voltage, for self-adhesive cable joints, E is taken as... t =0.3~1KV / mm.

[0117] Step c: Determine the cutting diameter and its design requirements;

[0118] The conductor diameters of 10KV cables of different specifications are shown in Table 1 below:

[0119] Table 1. Cable Diameters of Different Specifications

[0120]

[0121] Continued from table:

[0122] Cables of different specifications have different conductor diameters. The outer diameter of a single cable is the sum of the conductor diameter, insulation thickness, conductor shielding thickness, and the combined thickness of the insulation shielding thickness; for example... Figure 11 The diagram shown is a schematic of the cable structure.

[0123] As mentioned earlier, the insulation layer thickness of 10KV cables is uniformly 4.5mm. Therefore, the shape of the cutting tool in the forming device design does not need to be changed. The position of the cutting tool needs to be adjustable back and forth to adapt to cables of different specifications.

[0124] Step d: Determine the number of cutting tools to be used in the forming device;

[0125] A typical cutting device usually consists of a rotary mechanism that drives a single cutting tool to rotate and perform the cutting motion. First, the concentricity of a single cutting tool is affected by the machining process, which can easily cause the workpiece to become eccentric during the cutting process. Second, a single cutting tool is subjected to a large force during the cutting process, requiring a large motor power and making the motor prone to damage. Finally, when a single cutting tool is cutting a cable, because the force is only applied to one side, the cable is prone to swaying from side to side, affecting the cutting process.

[0126] Based on a thorough understanding of the shortcomings of individual cutting tools, this design employs three sets of tools for simultaneous cutting. The three sets of tools perform simultaneous cutting via turning, and the tools utilize a complex logarithmic curve design. This approach offers the following advantages:

[0127] 1. Ensure concentricity. Simultaneous cutting with three sets of tools effectively guarantees the precision of the workpiece.

[0128] 2. A three-pronged approach reduces motor power. With three sets of cutting tools cutting simultaneously, the cutting force of a single tool is theoretically shared by all three, thus reducing motor power.

[0129] 3. The cable is subjected to uniform force, and the cutting is carried out smoothly. The three sets of cutters are evenly distributed on the circumference, so that the cable is subjected to uniform force during the cutting process and will not sway from side to side.

[0130] Step e: Determine the cutting speed;

[0131] The cutting speed of the reactive force cone is mainly affected by several factors, including the main insulation material of the cable, the heat generated during the cutting process of the tool, and the overall dynamic balance of the cutting device.

[0132] Currently, the main insulation material for 10kV cables is cross-linked polyethylene, which has been described in detail earlier. It has stable chemical properties, good heat resistance, and a long-term allowable operating temperature of 90℃. It also has good mechanical properties and is easy to process and handle.

[0133] The heat generated by friction during cutting is also a significant factor affecting cutting speed. Heat is inevitably generated during cutting; the higher the cutting speed, the more intense the friction, and the more heat is generated. Excessive heat may cause adhesion to the main insulation, thus affecting the formation of the reactive force cone.

[0134] The overall dynamic balance of the equipment during operation is also related to the cutting speed. Due to the inhomogeneity of the material structure, the dimensional errors of the part's shape, the errors in the assembly dimensions, and the structural shape, the rotating parts will generate unbalanced centrifugal forces. Especially for high-speed rotating parts, which rotate more than ten times per second, even a very small eccentric moment can cause a large unbalanced force, thus causing oscillation during the cutting process.

[0135] Example 4

[0136] like Figure 12-16 As shown, in order to process the reactive force cone mentioned in the previous embodiments, this embodiment provides a reactive force cone cutting device for the main insulation layer of a 10kV distribution network cable. The specific structure and principle are as follows:

[0137] A reaction force cone cutting device for the main insulation layer of a 10kV distribution cable includes an annular shell 1. The annular shell 1 has a U-shaped cross-section with its opening facing inward. A rotating ring 2 is embedded and rotatably installed in the inner ring of the annular shell 1. The rotating ring 2 and the annular shell 1 can be rotatably installed by embedding ball bearings.

[0138] An outer side of the annular shell 1 is provided with a drive device for driving the rotating ring 2 to rotate. Specifically, the drive device includes a drive motor 8, a drive gear 9 is installed at the output end of the drive motor 8, and an outer toothed ring 10 that meshes with the drive gear 9 is provided on the outer periphery of the rotating ring 2.

[0139] The inner ring of the rotating ring 2 has several mounting plates 3 arranged in a ring. Each mounting plate 3 is equipped with a tool holder 4 with a cutting tool 5. The cutting edge profile of the cutting tool 5 is consistent with the arc profile of the reactive force cone surface in the aforementioned embodiment, so as to facilitate the machining of a reactive force cone shape with a specific curve.

[0140] The tool holder 4 can move radially relative to the mounting plate 3 along the rotating ring 2. Specifically, a rectangular groove 19 is provided in the middle of the inner end of the mounting plate 3, and a sliding groove 20 is provided on each of the inner walls of the rectangular groove 19. The tool holder 4 is embedded in the rectangular groove 19, and sliding block protrusions 21 embedded in the sliding grooves 20 are provided on both sides of the tool holder 4. The sliding installation of the tool holder 4 is achieved by the cooperation of the sliding block protrusions 21 and the sliding grooves 20.

[0141] It also includes an adjustable annular disk assembly, which comprises two parallel and spaced annular disks 11, which are fixedly connected by several connecting posts 12. A rotating ring 2 is clamped between the two annular disks 11 and rotatably mounted. Several arc-shaped grooves 6 corresponding to each tool holder 4 are arranged in a ring on the upper and lower annular disks 11.

[0142] The distance between each point on the arc-shaped groove 6 and the center of the adjustable annular disk group gradually increases / decreases. The tool holder 4 is provided with a sliding pin 7 embedded in the arc-shaped groove 6 and slidably connected to it. The rotation of the adjustable annular disk group can synchronously drive each tool holder 4 to converge or disperse towards the center of the rotating ring 2. During the adjustment operation, it is only necessary to rotate the annular disk 11 relative to the annular shell 1 to make the sliding pin 7 slide in the arc-shaped groove 6. Since the distance from each point on the arc-shaped groove 6 to the center is not equal, this structure can be used to drive each tool holder 4 to move towards the middle or outward to achieve the adjustment, so as to be suitable for the processing of the reactive force cone surface of cables with different wire diameters. More importantly, the processing of the reactive force cone requires ensuring the coaxial accuracy between the cone surface and the mandrel. Through the linkage adjustment of each tool holder 4, it can be ensured that the advance and retreat of each tool holder 4 are uniform, and that the center remains unchanged before and after the adjustment, thereby ensuring the coaxial accuracy between the cone surface of the reactive force cone and the mandrel.

[0143] To facilitate adjustment and accommodate cables of any diameter, one of the annular discs 11 in this device has a conical external gear ring 13 on its outer edge. The outer wall of the annular shell 1 and the conical external gear ring 13 are respectively provided with a fixing plate 14. An adjusting shaft 15 is rotatably mounted on the fixing plate 14. One end of the adjusting shaft 15 is equipped with a bevel gear 16 that meshes with the conical external gear ring 13, and the other end is provided with a hand-tightening handle 17. A positioning nut 18 is screwed onto the adjusting shaft 15. After the positioning nut 18 is tightened, it abuts against the fixing plate 14 to restrict the rotation of the adjusting shaft 15. During adjustment, the adjusting shaft 15 is rotated by turning the handle 17, which in turn drives the bevel gear 16 to drive the external conical gear ring 13 on the annular disk 11 to rotate, thus rotating the annular disk 11 to adjust the distance. Since a large transmission ratio can be set between the bevel gear 16 and the external conical gear ring 13, this structure can achieve more precise tool feed and retraction adjustment, thereby improving the machining accuracy of this device from the perspective of machining feed. In addition, the positioning nut 18 is designed to limit the adjusting shaft 15 to ensure that no offset error will occur during the machining process after the feed is adjusted to the correct position.

[0144] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A process for treating the reactive force cone of the main insulation layer of a 10kV distribution cable, characterized in that: Including processing steps: Equipment component inspection, cable sheath removal, copper shielding and semi-conductive conductive layer removal, stress tube fixing, reactive force cone cutting, connecting pipe crimping, semi-conductive tape wrapping and filler adhesive wrapping, insulating pipe fixing, shielding mesh and grounding wire installation, sheath fixing, power-on operation and acceptance. The cutting reaction force cone step specifically includes the following processing steps: Step a: Determine the starting position for cable cutting; Step b: Determine the length of the reactive force cone; Step c: Determine the cutting diameter and its design requirements; Step d: Determine the number of cutting tools to be used in the forming device; Step e: Determine the cutting speed; In step b, the length Lc and shape of the stress cone are designed so that the axial field strength of its surface is equal to or less than its maximum allowable axial field strength. The length Lc of the reactive force cone can be calculated using the following formula: In the formula: —Cable insulation radius —Increase the radius of the insulation winding — Core radius In the formula, U is the design voltage of the cable joint, which is 1.1 times the power frequency test voltage. Referring to the American IEEE Standard, when U is the design voltage, for self-adhesive cable joints, take... =0.3~1KV / mm.

2. The reactive cone treatment process for the main insulation layer of a 10kV distribution cable as described in claim 1, characterized in that: In step a, according to the provisions on connecting pipes in GB 14315-93 "Crimped Copper and Aluminum Terminals and Connecting Pipes for Conductors of Power Cables", the material and length of the connecting pipe are determined in combination with the cross-sectional area and material of the cable core, and then the starting position of the reaction force cone cutting is determined.

3. The reactive cone treatment process for the main insulation layer of a 10kV distribution cable as described in claim 1, characterized in that: In step c, the insulation layer thickness of the 10KV cable is consistently 4.5mm. The shape of the cutting tool in the forming device design does not need to be changed, but the position of the cutting tool needs to be adjustable back and forth to adapt to cables of different specifications.

4. The reactive force cone treatment process for the main insulation layer of a 10kV distribution cable as described in claim 1, characterized in that: In step d, three sets of tools are used to cut simultaneously by turning, and the tools are designed with complex logarithmic curves.

5. The reactive cone treatment process for the main insulation layer of a 10kV distribution cable as described in claim 1, characterized in that: In step e, the factors to be considered in determining the cutting speed include the main insulation material of the cable, the heat generated during the cutting process of the tool, and the overall dynamic balance of the cutting device.

6. A reaction force cone cutting device for the main insulation layer of a 10kV distribution cable, characterized in that: The device includes an annular outer shell (1), in which a rotating ring (2) is embedded and rotatably mounted. A driving device for driving the rotating ring (2) is provided on one outer side of the annular outer shell (1). Several mounting plates (3) are arranged in a ring around the inner ring of the rotating ring (2). Each mounting plate (3) is equipped with a tool holder (4) containing a cutting tool (5). The cutting edge profile of the cutting tool (5) is consistent with the arc-shaped profile of the reactive force cone surface as described in any one of claims 1-5. The tool holder (4) can be positioned relative to the... The mounting plate (3) moves radially along the rotating ring (2) and also includes an adjustable annular disk group. Several arc-shaped grooves (6) corresponding to each of the tool holders (4) are arranged in a ring on the disk surface of the adjustable annular disk group. The distance between each point on the arc-shaped groove (6) and the center of the adjustable annular disk group gradually increases / decreases. The tool holder (4) is provided with a sliding pin (7) that is embedded in the arc-shaped groove (6) and slidably connected to it. The rotation of the adjustable annular disk group can synchronously drive each tool holder (4) to converge or disperse towards the center of the rotating ring (2).

7. The reactive force cone cutting device for the main insulation layer of a 10kV distribution cable as described in claim 6, characterized in that: The driving device includes a drive motor (8), a drive gear (9) is installed at the output end of the drive motor (8), and an external gear ring (10) is provided on the outer periphery of the rotating ring (2) to mesh with the drive gear (9).

8. The reactive force cone cutting device for the main insulation layer of a 10kV distribution cable as described in claim 6, characterized in that: The adjustable annular disk assembly includes two parallel annular disks (11) spaced apart. The two annular disks (11) are fixedly connected by several connecting columns (12). The rotating ring (2) is sandwiched between the two annular disks (11) and rotated.

9. The reaction force cone cutting device for the main insulation layer of a 10kV distribution cable as described in claim 8, characterized in that: One of the annular disks (11) has a conical external gear ring (13) on its outer edge. The annular outer shell (1) has a fixing plate (14) on its outer wall corresponding to the conical external gear ring (13). An adjusting shaft (15) is rotatably mounted on the fixing plate (14). One end of the adjusting shaft (15) is equipped with a bevel gear (16) that meshes with the conical external gear ring (13), and the other end is equipped with a hand-tightening handle (17). A positioning nut (18) is screwed onto the adjusting shaft (15). After the positioning nut (18) is tightened, it abuts against the fixing plate (14) to restrict the rotation of the adjusting shaft (15).

Images