Medium voltage fire resistant cable and its terminal processing technology

Abstract

The application discloses a medium-voltage fireproof cable, which comprises a cable body, the cable body comprises three copper conductors, an inner shielding layer located outside the copper conductors, a crosslinked polyethylene insulation layer located outside the inner shielding layer, a metal shielding layer wrapped outside the three copper conductors, a wrapping tape located outside the metal shielding layer, and an outer sheath located outside the wrapping tape; a plurality of cavity layers are arranged inside the periphery of the outer sheath; the plurality of cavity layers are uniformly and interval distributed along the periphery of the outer sheath; a plurality of partitions are arranged in the cavity layers and uniformly and interval distributed along the extending direction of the cavity layers; and naphthol powder is arranged between the adjacent two partitions in the cavity layers. When rodents and insects bite and bite open the cavity layers of the outer sheath, the naphthol powder is exposed in the air, at this time, the rodents and insects can be driven away through the irritating smell of the naphthol powder, and finally the cable body can be effectively protected.

Description

Technical Field

[0001] This invention belongs to the field of cable production technology, and specifically relates to a medium-voltage fireproof cable and its terminal processing technology. Background Technology

[0002] Medium-voltage cables have a voltage range of 6KV to 33KV and are used in petrochemical, transportation, wastewater treatment, food processing and other fields.

[0003] Chinese patent with publication number CN110707611 and publication date of January 17, 2020 discloses an improved installation process for cold-shrink terminals of three-core cables, which includes the following steps: stripping the outer sheath of the cable, installing the steel armor ground wire, installing the shield ground wire, installing the three-finger sleeve, stripping the insulation layer, and installing the cold-shrink terminal.

[0004] The improved installation process for cold-shrinkable terminals of three-core cables discloses the processing technology of the cable ends, which includes, in sequence, stripping the outer sheath of the cable, installing the steel armor ground wire, installing the shield ground wire, installing the three-finger sleeve, stripping the insulation layer, and installing the cold-shrinkable terminal.

[0005] Meanwhile, Chinese patent publication number CN218826342U, published on April 7, 2023, discloses a flame-retardant, fire-resistant, and environmentally friendly medium-voltage power cable. The power cable includes a cable core, a flame-retardant heat dissipation layer, a cooling layer, a comprehensive fireproof layer, and an outer sheath. The cable core includes three metal-shielded insulated wire cores and a filler frame. The three metal-shielded insulated wire cores are twisted together, and the filler frame fills the area between the three metal-shielded insulated wire cores. Each metal-shielded insulated wire core includes a conductor, and the conductor is covered from the inside out with a conductor shielding layer, a plastic insulation layer, an insulation shielding layer, and a metal shielding layer. The cable core is covered from the inside out with a flame-retardant heat dissipation layer, a cooling layer, a comprehensive fireproof layer, and an outer layer.

[0006] This type of flame-retardant, fire-resistant, and environmentally friendly medium-voltage power cable can achieve good fire protection by using a comprehensive fireproof layer; however, in the underground laying of the cable, the cable is often attacked by rodents and insects, which can lead to power outages. Summary of the Invention

[0007] The purpose of this invention is to provide a medium-voltage fireproof cable that can repel rodents and insects after they have bitten into the outer sheath.

[0008] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a medium-voltage fireproof cable, comprising a cable body, the cable body comprising three copper conductors, an inner shielding layer located outside the copper conductors, a cross-linked polyethylene insulation layer located outside the inner shielding layer, a metal shielding layer wrapped around the three copper conductors, a wrapping tape located outside the metal shielding layer, and an outer sheath located outside the wrapping tape. The outer sheath has multiple cavity layers inside its periphery, the multiple cavity layers being evenly spaced along the periphery of the outer sheath. Multiple partitions are evenly spaced along the extension direction of the cavity layer within the cavity layer, and naphthol powder is disposed within the cavity layer and between two adjacent partitions.

[0009] By adopting the above technical solution, multiple cavity layers are opened inside the outer sheath. The existence of the cavity layers can reduce the weight of the entire cable body, thus achieving cable lightweighting. At the same time, the cavity layers are separated by partitions, and naphthol powder is placed in the cavity layer between two adjacent partitions. When rodents and insects tear and bite open the cavity layer of the outer sheath, the naphthol powder can be exposed to the air. At this time, the irritating odor of the naphthol powder can repel rodents and insects, thus effectively protecting the cable body.

[0010] A further feature of the present invention is that the outer surface of the outer sheath is coated with a fluorocarbon fire-retardant coating layer.

[0011] By adopting the above technical solution, the fluorocarbon fire-retardant coating layer has a good fire-retardant effect, which ultimately helps to protect the cable body.

[0012] The present invention also aims to provide a terminal processing technology for medium-voltage fireproof cables, which can facilitate the processing of cable terminals for thicker cables.

[0013] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a terminal processing technology for medium-voltage fireproof cables, comprising the following steps, Step 1: Use the base to constrain and fix the ends of the cable body; Step 2: Use a cutting device to cut the outer sheath and wrapping tape; Step 3: Secure the ground wire to the stripped metal shielding layer; Step 4: Wrap tape around the grounding wire fixing point; Step 5: Install the three-finger sleeve, and pass the three copper conductors with cross-linked polyethylene insulation layers through the three branch tubes of the three-finger sleeve respectively; Step Six: Peel off the cross-linked polyethylene insulation layer and shielding layer from the ends of the copper conductor; Step 7: Install terminals at the ends of the copper conductors.

[0014] With the above technical solution, after the end of the cable body is constrained and fixed by the base, the outer sheath and the wrapping tape can be cut by the cutting device. Compared with the prior art where operators need to use a hacksaw to cut the outer surface of the relatively thick cable body, a large amount of labor can be saved, and finally the terminal of the cable body can be processed relatively conveniently.

[0015] The present invention is further configured as follows: the base includes two "⊓"-shaped fixing frames, a V-shaped clamping seat arranged in the middle of the upper side of the fixing frames, an internally threaded sleeve arranged in the middle of the upper side of the fixing frames and extending in the vertical direction, a locking threaded shaft threadedly connected in the internally threaded sleeve, and a locking plate arranged at the lower end of the locking threaded shaft and used for pressing the cable body into the bottom of the clamping seat.

[0016] With the above technical solution, the end of the cable body is inserted into the clamping seats on the two fixing frames, then the locking threaded shaft is rotated, the locking threaded shaft can push the locking plate to press the cable body into the bottom of the clamping seat, and finally the constraint and fixation of the end of the cable body can be realized.

[0017] The present invention is further configured as follows: the cutting device includes a support platform for supporting the end of the cable body, an annular cutting assembly arranged between the support platform and the base and used for performing circumferential cutting on the surface of the end of the cable body, and a horizontal cutting assembly arranged on the support platform and used for performing axial cutting on the surface of the end of the cable body. The annular cutting assembly includes a "⊓"-shaped mounting plate arranged between the base and the support platform, connecting shafts rotatably connected at four folded corners on the peripheral side of the mounting plate, a first rotating disc arranged at one end of the connecting shaft close to the mounting plate, a first snap ring arranged on the peripheral side of the first rotating disc, a transmission belt passing around the four first snap rings, a drive motor arranged on the mounting plate with an output shaft connected to any one of the connecting shafts, a second rotating disc arranged at one end of the connecting shaft far away from the mounting plate, a second snap ring arranged on the peripheral side of the second rotating disc, a rotating ring arranged between the four second rotating discs with its peripheral side embedded in the second snap ring, and a cutting member arranged on the rotating ring and used for performing circumferential cutting on the cable body as the rotating ring rotates.

[0018] With the above technical solution, the drive motor is started, the drive motor drives the connected connecting shaft to rotate, the connecting shaft can drive the transmission belt to transmit through the first rotating disc, the transmission of the transmission belt can simultaneously drive the four connecting shafts to rotate, then the four connecting shafts can drive the inner rotating ring to rotate through the second rotating disc, and the rotating ring can drive the cutting member to rotate around the peripheral side of the cable body, so that the cutting member can cut the peripheral side of the cable body.

[0019] The present invention is further configured as follows: the cutting member includes a seat sleeve located on the inner side of the rotating ring, a connecting plate disposed on the lower side of the seat sleeve, two connecting arms disposed on the lower side of the connecting plate, a cutting motor disposed at the lower end of the connecting arms, and a cutting blade disposed on the output shaft of the cutting motor and located between the two connecting arms. Both ends of the connecting plate are provided with first through holes, both ends of the seat sleeve are provided with threaded guide posts passing through the first through holes, the threaded guide post is sleeved with a compression spring whose one end abuts against the seat sleeve and the other end abuts against the connecting plate, and an adjusting nut is threadedly connected to the threaded guide post and located on the lower side of the connecting plate.

[0020] By adopting the above technical solution, after the cutting motor is started, the cutting motor can drive the cutting blade to rotate, and the outer wall of the cable body can be cut by the cutting blade; at the same time, the connecting plate can be driven to lift by rotating the adjusting nut, so as to adjust the height of the cutting blade, so that the cutting blade can be adjusted to a required position.

[0021] The present invention is further configured as follows: an open slot for the seat sleeve to be embedded is opened on the inner wall of the rotating ring, a second through hole extending in a vertically upward direction is opened in the open slot, a rotating shaft penetrates into the second through hole, the lower end of the rotating shaft is provided with a first guide shaft for embedding into the seat sleeve, the upper side of the seat sleeve is provided with a long hole for the rotating shaft to pass through, the upper end of the rotating shaft is provided with an end plate, and the rotating shaft is sleeved with a return spring whose one end abuts against the end plate and the other end abuts against the rotating ring.

[0022] By adopting the above technical solution, the first guide shaft is embedded in the seat sleeve, and the long hole on the seat sleeve allows the rotating shaft to pass through. At this time, the rotating shaft can drive the seat sleeve to rotate. When the circumferential side of the cable body needs to be cut, the elastic restoring force of the return spring drives the first guide shaft and the seat sleeve to move upward, then the seat sleeve can be embedded in the open slot on the inner wall of the rotating ring, the seat sleeve can be clamped through the open slot, so as to position the circumferential rotation of the seat sleeve. At this time, the cutting blade is parallel to the end face of the cable body, so the cutting blade can be used to cut the circumferential side of the cable body.

[0023] The present invention is further configured as follows: the horizontal cutting assembly includes portal frames in a "∩" shape disposed at both ends of the support platform, a second guide shaft disposed between the two portal frames and for the seat sleeve to be sleeved on, a first connecting rod disposed on the portal frame near the rotating ring and connected to the end of the second guide shaft, and a second connecting rod disposed on the portal frame far from the rotating ring and connected to the end of the second guide shaft. The width of the first connecting rod is smaller than the width of the long hole.

[0024] By adopting the above technical solution, when it is necessary to axially cut the cable body, the height of the cutting blade is adjusted by adjusting the adjusting nut, so that the cutting blade moves upward and a gap is created between the cutting blade and the cable body. Then, the end plate is pressed down, so that the rotating shaft drives the seat to move downward. Then, the seat can be dislodged from the opening slot. At this time, the end plate can be rotated to rotate the seat by 90 degrees, so that the first guide shaft is connected with the second guide shaft and the cutting blade is perpendicular to the end face of the cable body. After adjusting the height of the cutting blade by adjusting the adjusting nut, the cutting blade can cut the cable body axially. Then, the seat can be moved along the first guide shaft and then moved to the second guide shaft. The seat continues to move along the second guide shaft. At this time, the cutting blade can complete the axial cutting of the cable body. Finally, the cutting blade can switch between different cutting angles.

[0025] A further configuration of the present invention is as follows: a third guide shaft is provided on one side of the support platform, a swing arm is provided on the third guide shaft, a third through hole is provided at one end of the swing arm for the third guide shaft to pass through, a fixed shaft is rotatably connected at the end of the swing arm away from the third through hole, an auxiliary wheel for abutting against the outer wall of the cable body is provided on the fixed shaft, a driven bevel gear is provided at the end of the fixed shaft, and a driving bevel gear that meshes with the driven bevel gear is provided at the end of the output shaft of the cutting motor.

[0026] By adopting the above technical solution, after the swing arm swings towards the side closer to the cable body, the auxiliary wheel on the fixed shaft is pressed against the outer wall of the cable body. When the output shaft of the cutting motor drives the cutting blade to rotate, the output shaft of the cutting motor can drive the fixed shaft to rotate through the active bevel gear and the driven bevel gear. Finally, the auxiliary wheel can be driven to rotate at the cutting position on the outer wall of the cable body. At this time, the friction between the auxiliary wheel and the outer wall of the cable body helps the cut outer sheath to fall off the cable body, which is conducive to the rapid peeling of the outer sheath. Simultaneously, by pushing the swing arm, it can move along the third guide shaft, and then utilize the cutting damping force between the cutting blade and the cable body to make the driven bevel gear stably mesh with the driving bevel gear.

[0027] A further feature of the present invention is that a sliding sleeve with its lower surface in contact with the support platform is sleeved on the third guide shaft, and a compression torsion spring with one end connected to the sliding sleeve and the other end connected to the swing arm is sleeved on the third guide shaft.

[0028] By adopting the above technical solution, the torsional restoring force of the compression torsion spring is used to drive the swing arm to rotate toward the side closer to the cable body, which helps the auxiliary wheel to be stably pressed against the outer wall of the cable body. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a cross-sectional view of the cable body in this invention; Figure 2 This is a partial structural cross-sectional view of the inner and outer sheaths of the cable body in this invention; Figure 3 This is a schematic diagram of the structure of the base and cutting device in this invention; Figure 4 This is an enlarged view of the cutting device in this invention. At this time, the cutting blade moves along the second guide shaft to perform axial surface cutting on the cable body. Figure 5 This is an enlarged view of the annular cutting assembly in this invention. At this time, the cutting blade rotates circumferentially along the rotating ring to perform circumferential cutting on the surface of the cable body. Figure 6 This is an exploded view of the connection relationship between the rotating ring and the cutting component in this invention; Figure 7 This is an enlarged view of the structure of the cutting component in this invention; Figure 8 This is an enlarged view of the structure of the support platform near the annular cutting component in this invention.

[0031] In the diagram, 1. Cable body; 11. Copper conductor; 12. Inner shielding layer; 13. Cross-linked polyethylene insulation layer; 14. Metal shielding layer; 15. Wrapping tape; 16. Outer sheath; 161. Cavity layer; 162. Partition plate; 163. Naphthol powder; 17. Fluorocarbon fire-retardant coating layer; 2. Base; 21. Fixing frame; 22. Card holder; 23. Internal threaded sleeve; 24. Locking threaded shaft; 25. Locking plate; 3. Support platform; 31. Third guide shaft; 32. Swing arm; 321. Third through hole; 322. Fixed shaft; 3221. Auxiliary wheel; 3222. Driven bevel gear; 33. Sliding sleeve; 34. Compression torsion spring; 4. Annular cutting assembly; 401. Mounting plate; 402. Connecting shaft; 403. First turntable; 404. 405. Snap ring; 406. Drive belt; 407. Drive motor; 408. Second turntable; 409. Second snap ring; 4091. Rotating ring; 4092. Opening slot; 4093. Second through hole; 4094. Rotating shaft; 40931. End plate; 40932. Return spring; 4094. First guide shaft; 41. Cutting part; 411. Seat sleeve; 4111. Threaded guide post; 4112. Compression spring; 4113. Adjusting nut; 4114. Long hole; 412. Connecting plate; 4121. First through hole; 413. Connecting arm; 414. Cutting motor; 4141. Drive bevel gear; 415. Cutting blade; 5. Horizontal cutting assembly; 51. Gantry; 52. Second guide shaft; 53. First connecting rod; 54. Second connecting rod. Detailed Implementation

[0032] The technical solutions in the embodiments will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0033] A medium-voltage fireproof cable, as per reference Figure 1 , Figure 2The medium-voltage fire-resistant cable includes a cable body 1, wherein the cable body 1 comprises, from the inside to the outside, three copper conductors 11, an inner shielding layer 12 located outside the copper conductors 11, a cross-linked polyethylene insulating layer 13 located outside the inner shielding layer 12, a metal shielding layer 14 wrapping the three copper conductors 11, a wrapping tape 15 located outside the metal shielding layer 14, an outer sheath 16 located outside the wrapping tape 15, and a fluorocarbon fire-retardant coating layer 17 located outside the outer sheath 16. Meanwhile, a plurality of cavity layers 161 are formed inside the peripheral side of the outer sheath 16, and the plurality of cavity layers 161 are evenly spaced along the peripheral side of the outer sheath 16. A plurality of partition plates 162 are integrally disposed in the cavity layer 161, and the plurality of partition plates 162 are evenly spaced along the extending direction of the cavity layer 161. At the same time, naphthol powder 163 is disposed in the cavity layer 161 and between two adjacent partition plates 162. Naphthol is a colorless or yellow rhombic crystal or powder with an unpleasant phenolic odor, and turns dark brown under light irradiation.

[0034] Principle: When rodents and insects bite the outer sheath 16 and bite through the cavity layer 161, the naphthol powder 163 will be exposed to the air. At this time, the pungent odor of the naphthol powder 163 can repel rodents and insects, so that the cable body 1 can be effectively protected finally.

[0035] A terminal processing process for a medium-voltage fire-resistant cable comprises the following steps: Step 1: Restrain and fix the end of the cable body by using a base; Step 2: Cut the outer sheath and the wrapping tape by using a cutting device; Step 3: Fix the ground wire on the de-varnished metal shielding layer; Step 4: Wrap the fixing part of the ground wire with adhesive tape; Step 5: Install a three-finger sleeve, and respectively pass the three copper conductors with the cross-linked polyethylene insulating layer through the three branch pipes of the three-finger sleeve; Step 6: Strip the cross-linked polyethylene insulating layer and the shielding layer at the end of the copper conductor; Step 7: Install a wiring terminal at the end of the copper conductor.

[0036] Reference Figure 3 The base 2 in step 1 comprises a fixing frame 21, a clamping seat 22, an internally threaded sleeve 23, a locking threaded shaft 24 and a locking plate 25. Two fixing frames 21 are arranged and fixed on the ground at intervals, and the fixing frames 21 are in a "∩" shape. Meanwhile, the clamping seat 22 is integrally arranged at the middle part of the upper side of the fixing frame 21, and the clamping seat 22 is V-shaped. The internally threaded sleeve 23 is integrally arranged at the middle part of the upper side of the fixing frame 21, and the internally threaded sleeve 23 extends in the vertical direction. At the same time, the locking threaded shaft 24 is in threaded connection with the internally threaded sleeve 23, and the lower end of the locking threaded shaft 24 penetrates into the clamping seat 22. The locking plate 25 is welded at the lower end of the locking threaded shaft 24 and used for pressing the cable body against the inner bottom of the clamping seat 22.

[0037] Reference Figure 3 The cutting device in step two includes a support platform 3, an annular cutting assembly 4, and a horizontal cutting assembly 5. The support platform 3 is located on one side of the base 2 and provides support for the end of the cable body. The annular cutting assembly 4 is disposed between the support platform 3 and the base 2 and is used to perform circumferential surface cutting on the end of the cable body. Meanwhile, the horizontal cutting assembly 5 is disposed on the support platform 3 and is used to perform axial surface cutting on the end of the cable body.

[0038] Reference Figure 3 , Figure 4 , Figure 5 The annular cutting assembly 4 includes a mounting plate 401, a connecting shaft 402, a first turntable 403, a first retaining ring 404, a transmission belt 405, a drive motor 406, a second turntable 407, a second retaining ring 408, a rotating ring 409, and a cutting element 41. The mounting plate 401 is positioned between the base 2 and the support platform 3 and is in a "U" shape. The center of the mounting plate 401 allows the cable body to pass through. The connecting shaft 402 is rotatably connected to the four corners of the mounting plate 401 via bearing seats. The first turntable 403 is integrally mounted on the end of the connecting shaft 402 near the mounting plate 401, and the first retaining ring 404 is located around the first turntable 403. The transmission belt... 405 bypasses four first retaining rings 404, and the drive motor 406 is fixed to the mounting plate 401 by bolts and its output shaft is connected to any connecting shaft 402. At this time, the drive motor 406 can drive the transmission belt 405 through the four first turntables 403. Meanwhile, the second turntable 407 is integrally set at the end of the connecting shaft 402 away from the mounting plate 401, and the second retaining ring 408 is opened on the periphery of the second turntable 407. The rotating ring 409 is located between the four second turntables 407 and the center is for the cable body to pass through. The side of the rotating disk is embedded in the second retaining ring 408. At this time, the rotating disk can rotate around the cable body under the drive of the second turntable 407.

[0039] Reference Figure 5 , Figure 6 , Figure 7The cutting component 41 is mounted on the rotating ring 409 and is used to circumferentially cut the cable body as the rotating ring 409 rotates. This cutting component 41 includes a seat 411, a connecting plate 412, a connecting arm 413, a cutting motor 414, and a cutting blade 415. The seat 411 is located inside the rotating ring 409 and is rectangular in shape with a rectangular inner cross-section. The connecting plate 412 is located below the seat 411. Two connecting arms 413 are provided and welded to the lower side of the connecting plate 412. The cutting motor 414 is fixed to the lower end of the connecting arm 413 by bolts, and the output shaft of the cutting motor 414 passes through... The cutting blade 415 is fixed to the output shaft of the cutting motor 414 by bolts through the lower ends of the two connecting arms 413, and the cutting blade 415 is located between the two connecting arms 413. The connecting plate 412 has a first through hole 4121 at both ends, and the seat sleeve 411 has a threaded guide post 4111 welded through the first through hole 4121 at both ends. The threaded guide post 4111 is fitted with a compression spring 4112, one end of which is pressed against the seat sleeve 411 and the other end of which is pressed against the connecting plate 412. An adjusting nut 4113 is threadedly connected to the threaded guide post 4111 and located on the lower side of the connecting plate 412.

[0040] Reference Figure 5 , Figure 6 , Figure 7 An opening groove 4091 for the seat sleeve 411 to be inserted is provided on the inner wall of the rotating ring 409. A second through hole 4092 extending vertically upward is provided in the opening groove 4091. A rotating shaft 4093 is inserted into the second through hole 4092. A first guide shaft 4094 for being embedded in the seat sleeve 411 is welded to the lower end of the rotating shaft 4093. The cross-section of the first guide shaft 4094 is rectangular. An elongated hole 4114 for the rotating shaft 4093 to pass through is provided on the upper side of the seat sleeve 411. The width of the elongated hole 4114 is smaller than the cross-sectional width of the first guide shaft 4094. An end plate 40931 is welded to the upper end of the rotating shaft 4093. A return spring 40932 is fitted on the rotating shaft 4093, with one end abutting against the end plate 40931 and the other end abutting against the rotating ring 409.

[0041] Reference Figure 4this horizontal cutting assembly 5 includes a gantry 51, a second guide shaft 52, a first link 53, and a second link 54, wherein the gantry 51 is welded to both ends of the support platform 3 and is in a "冂" shape, the second guide shaft 52 is disposed between the two gantries 51 and allows the seat sleeve 411 to be sleeved thereon, and the cross-sectional shape of the second guide shaft 52 is identical to that of the first guide shaft 4094; meanwhile, the upper side of the first link 53 is welded to the gantry 51 on the side close to the rotating ring 409, the lower side thereof is welded to the end of the second guide shaft 52, and the width of the first link 53 is smaller than the width of the long hole 4114; wherein the upper side of the second link 54 is welded to the gantry 51 on the side away from the rotating ring 409, and the lower side thereof is welded to the end of the second guide shaft 52.

[0042] With reference to Figure 4 , Figure 8 , a third guide shaft 31 is further disposed on one side of the support platform 3, both ends of the third guide shaft 31 are fixed to the support platform 3 by bolts, the third guide shaft 31 is parallel to the second guide shaft 52, and the cross section of the third guide shaft 31 is circular, wherein a swing arm 32 is disposed on the third guide shaft 31, one end of the swing arm 32 is provided with a third through hole 321 for the third guide shaft 31 to pass through, so that the swing arm 32 can swing on the third guide shaft 31; meanwhile, a fixed shaft 322 is rotatably connected to the end of the swing arm 32 away from the third through hole 321 via a bearing, an auxiliary wheel 3221 for abutting against the outer wall of the cable body is keyed on the fixed shaft 322, wherein a driven bevel gear 3222 is further keyed to the end of the fixed shaft 322, and a driving bevel gear 4141 meshed with the driven bevel gear 3222 is keyed to the end of the output shaft of the cutting motor 414, so that the output shaft of the cutting motor 414 can simultaneously drive the auxiliary wheel 3221 to rotate; meanwhile, a rectangular parallelepiped sliding sleeve 33 is further sleeved on the third guide shaft 31, the lower surface of the sliding sleeve 33 fits on the support platform 3, and a compression torsion spring 34 with one end welded to the sliding sleeve 33 and the other end welded to the swing arm 32 is further sleeved on the third guide shaft 31.

[0043] Principle: When performing terminal cutting processing on a relatively thick cable body, first feed the end of the cable body into the clamping seats 22 on the two fixing frames 21, then rotate the locking threaded shaft 24, the locking threaded shaft 24 can push the locking plate 25 to press the cable body against the inner bottom of the clamping seat 22, so as to realize the restraint and fixation of the end of the cable body.

[0044] The cable body is then circumferentially cut. The first guide shaft 4094 is embedded in the seat 411, and the elongated hole 4114 on the seat 411 allows the rotating shaft 4093 to pass through. Under the elastic restoring force of the return spring 40932, the first guide shaft 4094 and the seat 411 are moved upward. Then the seat 411 can be embedded in the opening groove 4091 on the inner wall of the rotating ring 409. The opening groove 4091 can be used to lock the seat 411, thereby positioning the circumferential rotation of the seat 411. At this time, the cutting blade 415 is parallel to the end face of the cable body. At the same time, by rotating the adjusting nut 4113, the connecting plate 412 can be raised and lowered, thereby adjusting the height of the cutting blade 415 so that the cutting blade 415 can be adjusted to the required cutting position.

[0045] Start the drive motor 406, which drives the connecting shaft 402 connected to it to rotate. The connecting shaft 402 then drives the transmission belt 405 through the first turntable 403 to start transmission. The transmission belt 405 can simultaneously drive the four connecting shafts 402 to rotate. Then, the four connecting shafts 402 can drive the inner rotating ring 409 to rotate through the second turntable 407. The rotating ring 409 can then drive the cutting blade 415 to rotate around the circumference of the cable body. At this time, the cutting blade 415 can cut the circumference of the cable body.

[0046] After cutting the periphery of the cable body, axial cutting is required. First, adjust the height of the cutting blade 415 using the adjusting nut 4113, causing the cutting blade 415 to move upward and create a gap between the cutting blade 415 and the cable body. Then, press down on the end plate 40931, causing the rotating shaft 4093 to move the seat sleeve 411 downward. The seat sleeve 411 can then disengage from the opening slot 4091. At this point, rotating the end plate 40931 will rotate the seat sleeve 411 90 degrees, causing the first guide shaft 4... The first guide shaft 4094 is connected to the second guide shaft 52 and the cutting blade 415 is perpendicular to the end face of the cable body. After adjusting the height of the cutting blade 415 by adjusting the nut 4113, the cutting blade 415 can cut the cable body axially. Then the operator can move the seat 411 along the first guide shaft 4094 and then onto the second guide shaft 52. The seat 411 continues to move along the second guide shaft 52. At this time, the cutting blade 415 can complete the axial cutting of the cable body. Finally, the cutting blade 415 can switch between different angles.

[0047] When the seat 411 moves along the second guide shaft 52, the thrust generated by pushing the swing arm 32 drives the seat 411 to move along the second guide shaft 52. At this time, the driven bevel gear 3222 stably meshes with the driving bevel gear 4141. Therefore, when the output shaft of the cutting motor 414 drives the cutting blade 415 to rotate, the output shaft of the cutting motor 414 can drive the fixed shaft 322 to rotate through the driving bevel gear 4141 and the driven bevel gear 3222. Finally, the auxiliary wheel 3221 can be driven to rotate at the cutting position on the outer wall of the cable body. At this time, the friction between the auxiliary wheel 3221 and the outer wall of the cable body helps the cut outer sheath 16 to fall off the cable body. In the end, the cutting blade 415 can cut the cable body axially and help peel off the outer sheath 16 at the same time.

Claims

1. A medium-voltage fireproof cable, comprising a cable body (1), wherein the cable body (1) comprises three copper conductors (11), an inner shielding layer (12) located outside the copper conductors (11), a cross-linked polyethylene insulation layer (13) located outside the inner shielding layer (12), a metal shielding layer (14) wrapped around the three copper conductors (11), a wrapping tape (15) located outside the metal shielding layer (14), and an outer sheath (16) located outside the wrapping tape (15), characterized in that: A plurality of cavity layers (161) are opened in the inner portion of the peripheral side of the outer sheath (16), the plurality of cavity layers (161) are distributed at uniform intervals along the peripheral side of the outer sheath (16), a plurality of partition plates (162) distributed at uniform intervals along the extension direction of the cavity layers (161) are arranged in the cavity layers (161), and naphthol powder (163) is arranged in the cavity layer (161) and between two adjacent partition plates (162); The terminal processing process of the medium-voltage fire-resistant cable comprises the following steps, Step 1: Restrain and fix the end of the cable body by using a base; Step 2: Cut the outer sheath and the wrapping tape by using a cutting device; Step 3: Fix the ground wire on the de-painted metal shielding layer; Step 4: Wind an adhesive tape around the fixed part of the ground wire; Step 5: Install a three-finger sleeve, and respectively pass three copper conductors with cross-linked polyethylene insulating layers through the three branch pipes of the three-finger sleeve; Step 6: Strip the cross-linked polyethylene insulating layer and the shielding layer at the end of the copper conductor; Step 7: Install a connection terminal at the end of the copper conductor; The base (2) comprises two "∩"-shaped fixing frames (21), a V-shaped clamping seat (22) arranged at the middle part of the upper side of the fixing frame (21), an internally threaded sleeve (23) arranged at the middle part of the upper side of the fixing frame (21) and extending in the vertical direction, a locking threaded shaft (24) in threaded connection with the internally threaded sleeve (23), and a locking plate (25) arranged at the lower end of the locking threaded shaft (24) and used for pressing the cable body into the bottom of the clamping seat (22); The cutting device comprises a support platform (3) for supporting the end of the cable body, an annular cutting assembly (4) arranged between the support platform (3) and the base (2) and used for performing circumferential cutting on the surface of the end of the cable body, and a horizontal cutting assembly (5) arranged on the support platform (3) and used for performing axial cutting on the surface of the end of the cable body. The annular cutting assembly (4) comprises a "∩"-shaped mounting plate (401) arranged between the base (2) and the support platform (3), connecting shafts (402) rotatably connected to four folded corners of the peripheral side of the mounting plate (401), a first rotating disk (403) arranged at one end of the connecting shaft (402) close to the mounting plate (401), a first snap ring (404) arranged on the peripheral side of the first rotating disk (403), a transmission belt (405) bypassing the four first snap rings (404), a drive motor (406) arranged on the mounting plate (401) and having an output shaft connected with any one of the connecting shafts (402), a second rotating disk (407) arranged at one end of the connecting shaft (402) far away from the mounting plate (401), a second snap ring (408) arranged on the peripheral side of the second rotating disk (407), a rotating ring (409) arranged between the four second rotating disks (407) and having the peripheral side embedded in the second snap ring (408), and a cutting member (41) arranged on the rotating ring (409) and used for performing circumferential cutting on the cable body along with the rotation of the rotating ring (409).

2. The medium-voltage fireproof cable according to claim 1, characterized in that: A fluorocarbon fire-resistant coating layer (17) is further coated on the outer surface of the outer sheath (16).

3. The terminal processing technology of a medium-voltage fireproof cable according to claim 1, characterized in that: The cutting member (41) comprises a seat sleeve (411) located on the inner side of the rotating ring (409), a connecting plate (412) arranged on the lower side of the seat sleeve (411), two connecting arms (413) arranged on the lower side of the connecting plate (412), a cutting motor (414) arranged at the lower end of the connecting arm (413), and a cutting blade (415) arranged on the output shaft of the cutting motor (414) and located between the two connecting arms (413). Both ends of the connecting plate (412) are provided with first through holes (4121), both ends of the seat sleeve (411) are provided with threaded guide posts (4111) passing through the first through holes (4121). The threaded guide post (4111) is sleeved with a compression spring (4112) of which one end abuts against the seat sleeve (411) and the other end abuts against the connecting plate (412). On the threaded guide post (411) and on the lower side of the connecting plate (412), an adjusting nut (4113) is connected by threads.

4. The terminal processing technology of a medium-voltage fireproof cable according to claim 3, characterized in that: An open slot (4091) for embedding the seat sleeve (411) is formed on the inner wall of the rotating ring (409). A second through hole (4092) extending vertically upward is formed in the open slot (4091), a rotating shaft (4093) penetrates into the second through hole (4092). The lower end of the rotating shaft (4093) is provided with a first guide shaft (4094) for embedding into the seat sleeve (411). The upper side of the seat sleeve (411) is provided with a long hole (4114) for the rotating shaft (4093) to pass through. The upper end of the rotating shaft (4093) is provided with an end plate (40931). The rotating shaft (4093) is sleeved with a return spring (40932) of which one end abuts against the end plate (40931) and the other end abuts against the rotating ring (409).

5. The terminal processing technology of a medium-voltage fireproof cable according to claim 4, characterized in that: The horizontal cutting assembly (5) comprises portal frames (51) arranged at both ends of the support platform (3) and shaped like a "n", a second guide shaft (52) arranged between the two portal frames (51) and for the seat sleeve (411) to sleeve, a first connecting rod (53) arranged on the portal frame (51) near the rotating ring (409) and connected to the end of the second guide shaft (52), and a second connecting rod (54) arranged on the portal frame (51) far from the rotating ring (409) and connected to the end of the second guide shaft (52). The width of the first connecting rod (53) is smaller than the width of the long hole (4114).

6. The terminal processing technology of a medium-voltage fireproof cable according to claim 5, characterized in that: A third guide shaft (31) is arranged on one side of the support platform (3). A swing arm (32) is arranged on the third guide shaft (31). One end of the swing arm (32) is provided with a third through hole (321) for the third guide shaft (31) to pass through. A fixed shaft (322) is rotatably connected to the end of the swing arm (32) away from the third through hole (321). The fixed shaft (322) is provided with an auxiliary wheel (3221) for abutting against the outer wall of the cable body. The end of the fixed shaft (322) is provided with a driven bevel gear (3222). The end of the output shaft of the cutting motor (414) is provided with a driving bevel gear (4141) meshed with the driven bevel gear (3222).

7. The terminal processing technology of a medium-voltage fireproof cable according to claim 6, characterized in that: The third guide shaft (31) is fitted with a sliding sleeve (33) whose lower surface is attached to the support platform (3), and the third guide shaft (31) is fitted with a compression torsion spring (34) whose one end is connected to the sliding sleeve (33) and whose other end is connected to the swing arm (32).

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