A fireproof flame-retardant b1 class cable

Abstract

The application relates to the technical field of B1-grade cables, and discloses a fireproof and flame-retardant B1-grade cable which comprises a plurality of core conductors, a filling layer, a wrapping layer, a separation layer, an armor layer and a sheath which are sequentially arranged between the outer sides of the plurality of core conductors, a fastening cylinder base and a flame-retardant box body, the core conductors penetrate through the fastening cylinder base, the fastening cylinder base comprises a mounting cylinder segment and a fastening cylinder segment, the mounting cylinder segment is in abutment with the sheath and is used for fixing the fastening cylinder base to the sheath, a fastening assembly is arranged between the fastening cylinder segment and the separation layer and is used for preventing the filling layer, the wrapping layer and the separation layer from loosening, the flame-retardant box body is connected with one side of the fastening cylinder base, the core conductors penetrate through the flame-retardant box body, a separation and communication structure is arranged in the flame-retardant box body, and flame-retardant particles are filled in the separation and communication structure. Through the technical scheme, the problem that the flame-retardant performance of the electrical connection between the B1-grade cable and the power equipment is poor in the prior art is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of B1 level cable, in particular to a fireproof and flame-retardant B1 level cable. BACKGROUND

[0002] B1 level cable refers to the power cable with certain flame-retardant performance according to international standards, compared with ordinary power cable, B1 level cable can effectively reduce the flame burning speed and prevent the spread of flame, and is commonly used in public places with dense flow and large-scale cable installation area to reduce the damage to power system when fire occurs. In the production and processing process of B1 level cable, the sheath, isolation layer and filling layer and other structures are all made of materials with flame-retardant performance. The sheath and isolation layer are all extruded by low-temperature, low-smoke and flame-retardant plastic materials to ensure the fireproof and flame-retardant performance of B1 level cable.

[0003] When the B1 level cable is electrically connected with the power equipment, the sheath, isolation layer and wrapping layer of the B1 level cable skin are first stripped off to expose the multiple core conductors of the B1 level cable for electrical connection with different power elements of the power equipment. The special sheath, isolation layer and wrapping layer are used to make the B1 level cable have good flame-retardant performance. Therefore, the electrical connection part of the B1 level cable and the power equipment is relatively easy to burn, and the flame-retardant performance of the B1 level cable is greatly reduced due to the lack of protection of the sheath, isolation layer and wrapping layer, which can cause uncontrollable damage to the power system when fire occurs. SUMMARY

[0004] The present application provides a fireproof and flame-retardant B1 level cable to solve the problem of poor flame-retardant performance of the electrical connection part of the B1 level cable and the power equipment in the prior art.

[0005] The technical scheme of the present application is as follows: a fireproof and flame-retardant B1 level cable, comprising multiple core conductors, a filling layer, a wrapping layer, an isolation layer, an armor layer and a sheath are sequentially arranged between the outer sides of the multiple core conductors, and further comprising:

[0006] A fastening cylinder seat, the core conductors penetrate through the fastening cylinder seat, the fastening cylinder seat comprises a mounting cylinder segment and a fastening cylinder segment, the mounting cylinder segment is in abutment with the sheath and is used to fix the fastening cylinder seat to the sheath, and a fastening assembly is arranged between the fastening cylinder segment and the isolation layer to prevent the filling layer, the wrapping layer and the isolation layer from loosening;

[0007] A flame-retardant box body connected with one side of the fastening cylinder seat, the core conductors penetrate through the flame-retardant box body, a partition communication structure is arranged in the flame-retardant box body, and flame-retardant particles are filled in the partition communication structure.

[0008] The flame-retardant protection structure is arranged between the area where each of the core wire conductors extends out of the flame-retardant box body and the flame-retardant box body, and is used for preventing the flame from spreading along the core wire conductors.

[0009] In order to fix the fastening cylinder seat to the sheath, further, a plurality of arc-shaped mounting pieces are fixedly connected to the inner circumference of the mounting cylinder segment, the arc-shaped mounting pieces are all arranged in the mounting cylinder segment in an inclined manner, a plurality of fastening particles are arranged on the inner arc surface of the arc-shaped mounting pieces, and the fastening particles are attached to the sheath.

[0010] In order to keep the sheath and the inside of the fastening cylinder seat sealed, further, a rubber ring is arranged in the mounting cylinder segment, and the inner wall of the rubber ring is attached to the sheath.

[0011] In order to prevent the filling layer, the wrapping layer and the isolation layer from loosening, further, the fastening assembly comprises a plurality of arc-shaped fastening members, an elastic metal clamp is arranged between the inner wall of the fastening cylinder segment and the arc-shaped fastening member, and the inner arc surface of the arc-shaped fastening member is in contact with the isolation layer.

[0012] In order to connect the fastening cylinder seat and the flame-retardant box body, further, engaging insertion grooves are fixedly connected to the upper and lower sides of the flame-retardant box body, two engaging insertion plates are fixedly connected to one end of the fastening cylinder seat close to the flame-retardant box body, the engaging insertion plates are inserted into the engaging insertion grooves and connected.

[0013] In order to prevent the plurality of core wire conductors from contacting each other, further, the separation and communication structure comprises a rectangular separation piece and a curved wire running channel, the rectangular separation piece is fixedly connected in the flame-retardant box body, the flame-retardant box body is divided into an outer flame-retardant chamber and an inner flame-retardant chamber by the rectangular separation piece, a plurality of wire running ports are arranged on both sides of the inner flame-retardant chamber in correspondence, the curved wire running channel is in communication between the corresponding two wire running ports, and the core wire conductors penetrate through the curved wire running channel.

[0014] In order to separately fill the heat insulation particles into the outer flame-retardant chamber and the inner flame-retardant chamber, further, an inlet valve pipe one is in communication with the outer flame-retardant chamber, an inlet valve pipe two is in communication with the inner flame-retardant chamber, and the inlet valve pipe two penetrates through the outer flame-retardant chamber.

[0015] In order to prevent the flame from spreading along the core wire conductors, further, the flame-retardant protection structure comprises isolation cylinder bodies and flexible curved cylinder bodies, the number of the isolation cylinder bodies is plural, one of the isolation cylinder bodies is fixedly connected to the flame-retardant box body, an isolation assembly is arranged between the isolation cylinder body and the core wire conductor, and the flexible curved cylinder bodies are in communication between adjacent two isolation cylinder bodies.

[0016] In order to improve the flame resistance of the isolation cylinder, further, the isolation assembly comprises isolation rings, both sides of the isolation cylinder are fixedly connected with the isolation rings, the inner arc surfaces of the isolation rings are in contact with the core conductor, and a plurality of heat dissipation connecting pieces are fixedly connected between the two isolation rings.

[0017] The working principle and beneficial effects of the present application are as follows:

[0018] In the present application, after the filling layer, the wrapping layer, the isolation layer, the armored layer and the sheath of the core conductor are stripped, the filling layer, the wrapping layer and the isolation layer are stripped by a section less than the sheath, the core conductor is penetrated through the fastening cylinder seat, the fastening cylinder seat is moved to the sheath, the plurality of arc-shaped mounting pieces are in contact with the sheath, the fastening cylinder seat is fixed on the sheath, and then the plurality of arc-shaped fasteners are used for fixing the isolation layer, so as to solve the problem that the core conductor is loose after the filling layer, the wrapping layer, the isolation layer, the armored layer and the sheath are stripped, and the flame is more easily spread to the inside.

[0019] In the present application, after the core conductor is penetrated through the flame-retardant box body, the core conductor is moved out of the flame-retardant box body through the curved wiring channel respectively, the mutual contact and entanglement between the plurality of core conductors can be prevented, the flame spreading problem can be solved, the core conductor can be protected by the flame-retardant particles to the greatest extent, and the burning problem at the joint between the core conductor and the power equipment can be effectively prevented.

[0020] In the present application, when the core conductor is moved out of the flame-retardant box body and electrically connected with the power equipment, the flame-retardant protection structure is sleeved on the core conductor region between the flame-retardant box body and the power equipment, the temperature insulation protection effect of the core conductor is achieved, the contact speed and the burning spread speed of the flame and the core conductor are slowed down, and the normal power supply time of the power system is delayed as much as possible. BRIEF DESCRIPTION OF DRAWINGS

[0021] The present application will be further described in detail below in combination with the drawings and specific embodiments.

[0022] Figure 1 It is a structural schematic diagram of the whole application;

[0023] Figure 2 It is a structural schematic diagram of the partial section of the application;

[0024] Figure 3 It is a structural schematic diagram of the cooperation of the core conductor, the filling layer, the wrapping layer, the isolation layer, the armored layer and the sheath in the present application;

[0025] Figure 4 It is a structural schematic diagram of the cooperation of the fastening cylinder seat, the flame-retardant box body, the arc-shaped mounting piece and the arc-shaped fastener in the present application.

[0026] Figure 5 Figure 1 is a schematic diagram of the partial cross-sectional plan structure of the fire-retardant box body, the rectangular partition, the curved wiring channel, the first material inlet valve pipe and the second material inlet valve pipe in the present application;

[0027] Figure 6 Figure 2 is a schematic diagram of the partial cross-sectional structure of the isolation cylinder body, the flexible curved cylinder body, the isolation ring sleeve and the heat dissipation connecting piece in the present application;

[0028] Figure 7 Figure 3 is a schematic diagram of the structure of the fastening cylinder seat and the engaging plugboard in the present application.

[0029] In the figure: 1, core conductor; 2, filling layer; 3, wrapping layer; 4, isolation layer; 5, armored layer; 6, sheath; 7, fastening cylinder seat; 8, mounting cylinder segment; 9, fastening cylinder segment; 10, fire-retardant box body; 11, arc-shaped mounting piece; 12, fastening particle; 13, rubber ring sleeve; 14, arc-shaped fastening piece; 15, elastic metal clamp; 16, engaging plug slot; 17, engaging plugboard; 18, rectangular partition; 19, outer fire-retardant chamber; 20, inner fire-retardant chamber; 21, curved wiring channel; 22, first material inlet valve pipe; 23, second material inlet valve pipe; 24, isolation cylinder body; 25, flexible curved cylinder body; 26, isolation ring sleeve; 27, heat dissipation connecting piece. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0031] As shown in Figures 1 to 7 the present embodiment, a fire-retardant B1-level cable is provided, which comprises a plurality of core conductors 1, and a filling layer 2, a wrapping layer 3, an isolation layer 4, an armored layer 5 and a sheath 6 are sequentially arranged between the outer sides of the plurality of core conductors 1. The core conductor 1 comprises a metal conductor and an insulation layer, and the metal conductor after being twisted is extruded with an insulation layer by an extrusion process to complete the preparation of the core conductor 1. The filling layer 2 and the wrapping layer 3 are both processed to the surface of the plurality of core conductors 1 in a cabling process. After cabling, an isolation layer 4 is extruded on the surface of the wrapping layer 3, and the armored layer 5 is processed on the surface of the isolation layer 4, and then a sheath 6 is extruded on the armored layer 5. The filling layer 2 can be a fire-retardant filler, and the isolation layer 4 is also a special fire-retardant material, which can block oxygen and has certain burn resistance. The outermost sheath 6 is also a low-smoke and burn-resistant material, which realizes the fire-retardant function of the whole core conductor 1.

[0032] As Figures 1 to 5 and Figure 7 shown, wherein, in actual electrical connection between the core conductor 1 and the power equipment, the sheath 6, the armor layer 5, the isolation layer 4, the wrapping layer 3 and the filling layer 2 need to be peeled off in turn, in the actual operation process, after completing the peeling operation, in order to avoid the peeling place being a neat opening, causing the filling layer 2, the wrapping layer 3, the isolation layer 4 and the armor layer 5 in the sheath 6 to be loose in the subsequent use process, the outside air enters the isolation layer 4, and the burning problem is aggravated when the fire occurs, the isolation layer 4, the wrapping layer 3 and the filling layer 2 can be selected to be peeled off less than the sheath 6 and the armor layer 5, so that the sheath 6 and the armor layer 5 are the same notch area, and the isolation layer 4, the wrapping layer 3 and the filling layer 2 are the same notch area;

[0033] Further comprising a fastening cylinder seat 7, the core conductor 1 penetrates through the fastening cylinder seat 7, the fastening cylinder seat 7 comprises a mounting cylinder segment 8 and a fastening cylinder segment 9, the mounting cylinder segment 8 abuts against the sheath 6, and is used for fixing the fastening cylinder seat 7 to the sheath 6; a plurality of arc-shaped mounting pieces 11 are fixedly connected to the inner circumference of the mounting cylinder segment 8, the plurality of arc-shaped mounting pieces 11 are all inclinedly arranged in the mounting cylinder segment 8, a plurality of fastening particles 12 are arranged on the inner arc surface of the arc-shaped mounting piece 11, the fastening particles 12 are in close contact with the sheath 6, after the core conductor 1 is moved out through the wire outlet hole formed in the fastening cylinder seat 7, the fastening cylinder seat 7 is moved towards the sheath 6, so that the fastening particles 12 arranged on the arc-shaped mounting piece 11 are in contact with the surface layer of the sheath 6, and the arc-shaped mounting piece 11 has a deformation characteristic, but the plurality of arc-shaped mounting pieces 11 arranged in the circumference have a uniform extrusion force on the sheath 6, so that the fastening cylinder seat 7 is fixed on the sheath 6.

[0034] The mounting cylinder segment 8 is provided with a rubber ring 13, the inner wall of the rubber ring 13 is in close contact with the sheath 6, when the fastening cylinder seat 7 is moved towards the sheath 6, the rubber ring 13 is in close contact with the sheath 6, so as to avoid the outside air and moisture in the air from entering the inside of the fastening cylinder seat 7, wherein the rubber ring 13 has a certain high-temperature resistance and will not melt when the fire initially occurs.

[0035] As Figures 1 to 5 and Figure 7As shown, the fastening cylinder segment 9 and the isolation layer 4 are provided with a fastening assembly for preventing the filling layer 2, the wrapping layer 3 and the isolation layer 4 from loosening, the fastening assembly comprises a plurality of arc-shaped fasteners 14, the arc-shaped fasteners 14 and the inner wall of the fastening cylinder segment 9 are provided with elastic metal clamps 15, the inner arc surface of the arc-shaped fastener 14 is in contact with the isolation layer 4, after the fastening cylinder seat 7 is sleeved on the surface of the sheath 6, the plurality of arc-shaped fasteners 14 are in contact with the isolation layer 4, and the arc-shaped fastener 14 inner wall and the isolation layer 4 are in full contact through the thrust generated after the elastic metal clamp 15 is deformed, so that the isolation layer 4, the wrapping layer 3 and the filling layer 2 are fastened, and the sheath 6, the armor layer 5, the isolation layer 4, the wrapping layer 3 and the filling layer 2 can fully play the flame-retardant effect when the core conductor 1 is electrically connected between the power equipment during the actual operation of the whole B1 level cable.

[0036] As shown in the figure, Figures 1 to 7 The flame-retardant box body 10 is connected to one side of the fastening cylinder seat 7, the core conductor 1 penetrates the flame-retardant box body 10, the upper and lower sides of the flame-retardant box body 10 are fixedly connected with engagement slots 16, the fastening cylinder seat 7 is fixedly connected with two engagement plugs 17 close to one end of the flame-retardant box body 10, the engagement plugs 17 extend into the engagement slots 16 and are connected, after the core conductor 1 penetrates the fastening cylinder seat 7, the side of the flame-retardant box body 10 is attached to the fastening cylinder seat 7, the engagement plugs 17 extend into the engagement slots 16, and the engagement plugs 17 and the engagement slots 16 are fixed by using bolts or other fasteners.

[0037] As shown in the figure, Figures 4 to 5 The flame-retardant box body 10 is provided with a partition communication structure, the partition communication structure is filled with flame-retardant particles, the partition communication structure comprises a rectangular partition 18 and a curved wiring channel 21, the flame-retardant box body 10 is fixedly connected with the rectangular partition 18, the rectangular partition 18 divides the flame-retardant box body 10 into an outer flame-retardant chamber 19 and an inner flame-retardant chamber 20, a plurality of wiring openings are formed on the two sides of the inner flame-retardant chamber 20, and the curved wiring channels 21 are in communication between the corresponding two wiring openings, the core conductor 1 penetrates the curved wiring channel 21, and the core conductor 1 is moved out of the flame-retardant box body 10 to between the plurality of isolation cylinder bodies 24 by penetrating the corresponding curved wiring channel 21, the core conductor 1 is moved in the curved wiring channel 21, so that the plurality of core conductors 1 are isolated from each other, on the one hand, the plurality of core conductors 1 can be uniformly and fully protected by the flame-retardant particles, and on the other hand, the influence on other core conductors 1 can be reduced when one of the core conductors 1 is on fire;

[0038] The outer fireproof chamber 19 is communicated with an inlet valve pipe one 22, and the inner fireproof chamber 20 is communicated with an inlet valve pipe two 23. The inlet valve pipe two 23 penetrates the outer fireproof chamber 19. The outer fireproof chamber 19 is filled with sufficient fireproof particles through the inlet valve pipe one 22, and the inner fireproof chamber 20 is filled with fireproof particles through the inlet valve pipe two 23, so as to improve the fireproof performance of the fireproof box 10. The inlet valve pipe one 22 and the inlet valve pipe two 23 are provided with closing valves, which prevent the fireproof particles from leaking in the outer fireproof chamber 19 and the inner fireproof chamber 20. The fireproof particles are common solid fireproof materials of cables with fireproof function in the prior art, have good heat insulation and high temperature resistance, and are known to those skilled in the art. The fireproof particles are widely used in the field of improving the fireproof performance of cables.

[0039] As shown in Figure 1 , Figure 2 , Figure 4 and Figure 6 , the area of each core conductor 1 extending out of the fireproof box 10 is provided with a fireproof protection structure between the fireproof box 10, which prevents the flame from spreading along the core conductor 1. The fireproof protection structure includes an isolation cylinder 24 and a flexible bending cylinder 25. The number of the isolation cylinders 24 is multiple. The isolation cylinders 24 are located on the outside of the core conductor 1. One of the isolation cylinders 24 is fixedly connected with the fireproof box 10. The isolation cylinders 24 are provided with an isolation assembly between the core conductor 1. The adjacent two isolation cylinders 24 are communicated with the flexible bending cylinder 25. The flexible bending cylinder 25 has the characteristics of bending and stretching, so that the multiple isolation cylinders 24 can fully protect the area of the core conductor 1 between the fireproof box 10 and the power equipment.

[0040] The isolation assembly includes an isolation ring 26. The isolation ring 26 is fixedly connected to the inside of the two sides of the isolation cylinder 24. The inner arc surface of the isolation ring 26 is in contact with the core conductor 1. The multiple heat dissipation connecting pieces 27 are fixedly connected between the two isolation rings 26 in the circumferential direction. When the fire occurs, the flame is burned into the isolation cylinder 24. The flame is effectively cut off through the sufficient contact between the isolation ring 26 and the core conductor 1, so that the flame does not spread rapidly and in a large area on the core conductor 1. The temperature of the surface of the isolation ring 26 burned on one side is rapidly dissipated into the isolation cylinder 24 through the heat dissipation connecting pieces 27, so as to reduce the influence of high temperature on the core conductor 1.

[0041] The working principle of the fireproof B1-level cable is as follows:

[0042] When the sheath 6, the armor layer 5, the isolation layer 4, the wrapping layer 3 and the filling layer 2 outside the core conductor 1 are peeled off in sequence, a section of the isolation layer 4, the wrapping layer 3 and the filling layer 2 can be peeled off less than the sheath 6 and the armor layer 5, so that the sheath 6 and the armor layer 5 have the same incision area, and the isolation layer 4, the wrapping layer 3 and the filling layer 2 have the same incision area. After the core conductor 1 is moved out through the wire hole formed in the fastening cylinder 7, the fastening cylinder 7 is moved towards the sheath 6, so that the fastening particles 12 arranged on the arc-shaped mounting plate 11 are in contact with the surface of the sheath 6. The arc-shaped mounting plate 11 has a deformation characteristic, but the plurality of arc-shaped mounting plates 11 arranged in a circle have a uniform extrusion force on the sheath 6, so that the fastening cylinder 7 is fixed on the sheath 6, and the rubber ring 13 is in contact with the sheath 6. Through the pushing force generated by the deformation of the elastic metal clamp 15, the arc-shaped fastening member 14 is in sufficient contact with the isolation layer 4, so as to fasten the isolation layer 4, the wrapping layer 3 and the filling layer 2;

[0043] After the core conductor 1 passes through the fastening cylinder 7, one side of the flame-retardant box body 10 is attached to the fastening cylinder 7, so that the engagement plug plate 17 extends into the engagement slot 16, and the engagement plug plate 17 and the engagement slot 16 are fixed by using a bolt or other fastening member. The core conductor 1 passes through the corresponding curved wiring channel 21 and is moved out of the flame-retardant box body 10 to between the plurality of isolation cylinder bodies 24. The flame-retardant particles are added into the outer flame-retardant chamber 19 through the inlet valve pipe one 22, and the flame-retardant particles are added into the inner flame-retardant chamber 20 through the inlet valve pipe two 23. After the core conductor 1 passes through the plurality of isolation cylinder bodies 24, the insulating layer outside the core conductor 1 is attached to the isolation ring 26, and the core conductor 1 is electrically connected to the power equipment.

[0044] The above is only a preferred embodiment of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A fire-retardant flame-retardant B1 level cable, comprising a plurality of core conductors (1), a plurality of said core conductors (1) are sequentially provided with a filling layer (2), a wrapping layer (3), a separation layer (4), an armor layer (5) and a sheath (6) between the outer sides of the plurality of core conductors (1), characterized in that, Also include: The fastening cylinder seat (7) is penetrated by the core conductor (1), the fastening cylinder seat (7) includes the installation cylinder section (8) and the fastening cylinder section (9), the installation cylinder section (8) is in abutment with the sheath (6), for fixing the fastening cylinder seat (7) on the sheath (6), the fastening cylinder section (9) is provided with a fastening assembly between the isolation layer (4), for preventing the filling layer (2), the wrapping layer (3) and the isolation layer (4) loose; The flame-retardant box body (10) is connected with one side of the fastening cylinder seat (7), the core conductor (1) penetrates the flame-retardant box body (10), and the flame-retardant box body (10) is provided with a partition communication structure, and the partition communication structure is filled with flame-retardant particles; The flame-retardant protection structure is provided with the flame-retardant protection structure on the area between the flame-retardant box body (10) and the power equipment, for preventing the flame from spreading along the core conductor (1).

2. A fire and flame retardant B1 class cable according to claim 1, characterised in that, A plurality of arc-shaped mounting pieces (11) are fixedly connected to the inner circumference of the installation cylinder section (8), and the plurality of arc-shaped mounting pieces (11) are inclinedly arranged in the installation cylinder section (8), a plurality of fastening particles (12) are arranged on the inner arc surface of the arc-shaped mounting piece (11), and the fastening particles (12) are attached to the sheath (6).

3. A fire and flame retardant B1 class cable according to claim 2, characterised in that, A rubber ring (13) is arranged in the installation cylinder section (8), and the inner wall of the rubber ring (13) is attached to the sheath (6).

4. A fire and flame retardant B1 class cable according to claim 3, characterised in that, The fastening assembly comprises: A plurality of arc-shaped fasteners (14) are arranged, an elastic metal clamp (15) is arranged between the inner wall of the fastening cylinder section (9) and the arc-shaped fastener (14), and the inner arc surface of the arc-shaped fastener (14) is in contact with the isolation layer (4).

5. A fire and flame retardant B1 class cable according to claim 2, characterised in that, Engagement slots (16) are fixedly connected to the upper and lower sides of the flame-retardant box body (10), two engagement plugboards (17) are fixedly connected to one end of the fastening cylinder seat (7) close to the flame-retardant box body (10), the engagement plugboards (17) are inserted into the engagement slots (16) and connected.

6. A fire and flame retardant B1 class cable according to claim 5, characterised in that, The partition communication structure comprises: A rectangular partition piece (18) is fixedly connected in the flame-retardant box body (10), and the rectangular partition piece (18) divides the flame-retardant box body (10) into an outer flame-retardant cavity (19) and an inner flame-retardant cavity (20); A curved wiring channel (21) is arranged in the flame-retardant box body (10), and the core conductor (1) penetrates the curved wiring channel (21).

7. A fire and flame retardant B1 class cable according to claim 6, characterised in that, An inlet valve pipe one (22) is communicated with the outer flame-retardant cavity (19), an inlet valve pipe two (23) is communicated with the inner flame-retardant cavity (20), and the inlet valve pipe two (23) penetrates the outer flame-retardant cavity (19).

8. A fire and flame retardant B1 class cable according to claim 7, characterised in that, The flame-retardant protection structure comprises: A plurality of isolation barrels (24) are arranged outside the core conductor (1), one of the isolation barrels (24) is fixedly connected with the flame-retardant box (10), and an isolation assembly is arranged between the isolation barrel (24) and the core conductor (1); A flexible bending barrel (25) is arranged between two adjacent isolation barrels (24).

9. A fire and flame retardant B1 class cable according to claim 8, characterised in that, The isolation assembly comprises: Two isolation rings (26) are fixedly connected to the inner sides of the isolation barrel (24), the inner arc surface of the isolation ring (26) is in contact with the core conductor (1), and a plurality of heat dissipation connecting pieces (27) are fixedly connected in the circumferences between the two isolation rings (26).

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