Search

CN-121812252-B - Mineral insulation fireproof cable and manufacturing process

CN121812252BCN 121812252 BCN121812252 BCN 121812252BCN-121812252-B

Abstract

The application relates to the field of cables and manufacturing processes, in particular to a mineral insulation fireproof cable and a manufacturing process, wherein the fireproof cable comprises a conductive part, an insulation part and a protection part, the conductive part comprises a multi-strand conductor and a conductor shielding layer for coating the multi-strand conductor, the insulation part comprises a mineral protection layer, the mineral protection layer coats the conductor shielding layer, the mineral protection layer comprises a binder matrix and refractory aggregate dispersed in the binder matrix, the binder matrix is of a continuous elastic structure, and the protection part comprises an isolation protection layer coated on the mineral protection layer, an armor layer coated on the isolation protection layer and a flame-retardant outer sheath coated on the armor layer.

Inventors

  • CHEN WEI
  • SHI XUEJUN
  • NIU YIFAN

Assignees

  • 上海浦东电线电缆(集团)有限公司

Dates

Publication Date
20260508
Application Date
20260307

Claims (9)

  1. 1.A mineral insulated fire protection cable comprising: a conductive part (1) comprising a stranded conductor (11) and a conductor shield layer (12) coating a plurality of strands of the stranded conductor (11); An insulating part (2) comprising a mineral protection layer (21), wherein the mineral protection layer (21) coats the conductor shielding layer (12), the mineral protection layer (21) comprises a binder matrix (211) and refractory aggregate (212) dispersed in the binder matrix (211), and the binder matrix (211) is of a continuous-phase elastic structure; The protection part (3) comprises an isolation protection layer (31) coated on the mineral protection layer (21), an armor layer (32) coated on the isolation protection layer (31) and a flame-retardant outer sheath (33) coated on the armor layer (32); The space between the conductor shielding layer (12) and the isolation protective layer (31) is an accommodating space (22) for accommodating the mineral protective layer (21), the mineral protective layer (21) further comprises a constraint net (213), the constraint net (213) divides the accommodating space (22) into a first accommodating part (221) and a second accommodating part (222), and the adhesive matrix (211) and the refractory aggregate (212) are respectively accommodated in the first accommodating part (221) and the second accommodating part (222).
  2. 2. A mineral insulated fireproof cable according to claim 1, characterized in that the first accommodation part (221) is located between the conductor shielding layer (12) and a restraining net (213), the second accommodation part (222) is located between the restraining net (213) and a shielding layer (31), and the distribution density of the refractory aggregate (212) located in the first accommodation part (221) is greater than the distribution density of the refractory aggregate (212) located in the second accommodation part (222).
  3. 3. The mineral insulated fireproof cable according to claim 2, wherein the conductor shielding layer (12) further comprises a plurality of limiting pieces (214) distributed along the length direction of the cable, the limiting pieces (214) comprise limiting rods (2141), and heat dissipation connecting rings (2142) formed at one ends of the limiting rods (2141), the conductor shielding layer (12) is sleeved on the heat dissipation connecting rings (2142), and the limiting rods (2141) penetrate through meshes of the constraint net (213).
  4. 4. A mineral insulated fireproof cable according to claim 3, wherein an end of the limit rod (2141) away from the heat dissipation connection ring (2142) is connected with an umbrella-shaped buffer cap (2144), a bottom surface of the umbrella-shaped buffer cap (2144) is abutted to an outer side surface of the constraint net (213), and a top surface of the umbrella-shaped buffer cap (2144) is abutted to an inner wall of the isolation protection layer (31).
  5. 5. The mineral insulated fireproof cable according to claim 4, wherein the heat dissipation connection ring (2142) is provided with a plurality of through holes (2143) along an annular surface thereof, and the outer circumferential surface of the conductor shielding layer is formed with limit flanges (2145) for abutting against two side wall surfaces of the heat dissipation connection ring (2142).
  6. 6. A mineral insulated fireproof cable according to claim 1, wherein the refractory aggregate (212) is a magnesium oxide powder modified with a silane coupling agent, and the binder matrix (211) comprises a silicone rubber and a glass frit dispersed in the silicone rubber.
  7. 7. A process for manufacturing a mineral insulated fire protection cable according to claim 5, characterized in that the process comprises the steps of: S1, mounting a plurality of limiting pieces (214) on the surface of a conductive part (1), enabling the heat dissipation connecting ring (2142) to be clamped between the limiting flanges (2145), and constructing an inner framework of an insulating part (2); S2, filling an adhesive matrix (211) and refractory aggregate (212) between the limiting members (214), filling the space of the first accommodating part (221), wrapping the constraint net (213) outside the first accommodating part (221), filling the adhesive matrix (211) and the refractory aggregate (212) outside the constraint net (213), filling the second accommodating part (222), and constructing a mineral protection layer (21); s3, heating and curing the mineral protection layer (21) until the adhesive matrix (211) is converted into a continuous-phase elastic structure; S4, sequentially coating an isolation protective layer (31) and an armor layer (32) on the outer side of the cured mineral protective layer (21).
  8. 8. A process for manufacturing a mineral insulated fire-resistant cable according to claim 7, characterized in that the construction of the mineral protection layer (21) in step S2 comprises the steps of: s21, mixing the adhesive matrix (211) with refractory aggregate (212) with high distribution density, filling the mixture on the surface of the conductive part (1), and controlling the filling thickness to be smaller than the height of the limiting rod (2141); s22, wrapping the constraint net (213), enabling the umbrella-shaped buffer cap (2144) to pass through meshes of the constraint net (213) by utilizing elastic deformation of the umbrella-shaped buffer cap, and enabling the umbrella-shaped buffer cap to be in contact with the outer side surface of the constraint net (213) after restoring deformation; S23, mixing the adhesive matrix (211) with the refractory aggregate (212) with low distribution density, filling the mixture on the surface of the constraint net (213), and covering the limiting piece (214) and the constraint net (213).
  9. 9. The process for manufacturing a mineral insulated fireproof cable according to claim 7, wherein the step S4 of coating the insulation protection layer (31) and the armor layer (32) comprises the following steps: S41, wrapping the isolation protective layer (31) and applying radial tension to enable the isolation protective layer (31) to compress the mineral protective layer (21) and be abutted against the limiting piece (214); S42, coating the armor layer (32) and enabling the armor layer (32) and the isolation protection layer (31) to form non-bonding sliding fit contact.

Description

Mineral insulation fireproof cable and manufacturing process Technical Field The application relates to the field of cables and manufacturing processes, in particular to a mineral insulation fireproof cable and a manufacturing process. Background The flexible mineral insulated fireproof cable is widely applied to places with extremely high requirements on fireproof grade, such as high-rise buildings, rail transit, petrochemical industry and the like. Such cables are typically composed of stranded conductors, a semiconductive shield coated over the conductors, and an outer layer of mineral insulating material, and flexible mineral insulated flame-retardant cables are currently typically composed of a copper sheath coated over a magnesia powder. However, in the practical laying process of the conventional flexible mineral insulated cable, the conventional loose powder filling structure cannot fix the powder position while maintaining flexibility, and under the action of repeated bending or axial tension generated by installation drop, circumferential shear force is easily generated inside the insulating part. The shearing force can cause slippage and accumulation of internal powder, uneven thickness of an insulating part is caused, even layering of the insulating part and a conductor shielding layer is caused, when a fire disaster high-temperature environment is encountered, after the binder is decomposed, the existing insulating part material often loses structural supporting force after high-temperature carbonization, powder is scattered, loose mineral powder can fall off due to hot air impact, and insulation failure is caused, so that a cable structure which can be suitable for laying at normal temperature and can maintain compact and non-loose structure at the whole fire disaster stage is needed. Disclosure of Invention In order to solve the technical problems in the prior art, the application provides a mineral insulation fireproof cable. The application provides a mineral insulation fireproof cable which adopts the following technical scheme: A mineral insulated fire-resistant cable comprising: a conductive part including a stranded conductor and a conductor shield layer coating the stranded conductor; The insulation part comprises a mineral protection layer, the mineral protection layer coats the conductor shielding layer, the mineral protection layer comprises a binder matrix and refractory aggregate dispersed in the binder matrix, the binder matrix is of a continuous elastic structure, and The protection part comprises an isolation protection layer coated on the mineral protection layer, an armor layer coated on the isolation protection layer and a flame-retardant outer sheath coated on the armor layer. Through adopting above-mentioned technical scheme, utilize the film forming of binder base member to wrap up refractory aggregate, combine into an organic whole with originally dispersed refractory aggregate to form the conductor shielding layer that has elasticity, thereby make the mineral inoxidizing coating be difficult for taking place brittle failure, eliminated the inside air gap that exists of insulating part simultaneously, avoid taking place to slide dislocation between the refractory aggregate in the cable bending process, guarantee cable structure's stability. Preferably, the space between the conductor shielding layer and the isolation protective layer is an accommodating space for accommodating the mineral protective layer, the mineral protective layer further comprises a constraint net, the constraint net divides the accommodating space into a first accommodating part and a second accommodating part, and the adhesive matrix and the refractory aggregate are respectively accommodated in the first accommodating part and the second accommodating part. According to the technical scheme, the mineral protection layer is divided into an inner layer structure and an outer layer structure in the thickness direction by the constraint net, the through holes distributed by the constraint net are used for enabling the adhesive matrix in the first containing part and the adhesive matrix in the second containing part to penetrate through the holes to realize mutual penetration and thermal fusion bonding, so that a mechanical interlocking structure is formed on two sides of the constraint net, the interface bonding strength is enhanced, layering inside the insulating part is prevented, meanwhile, the constraint net is used as an interlayer physical barrier, the radial expansion path of cracks from the second containing part to the first containing part is blocked, the integrity of a cable structure is ensured, and in addition, the constraint net can absorb heat, so that the heat dissipation performance of the cable is improved. Preferably, the first accommodating portion is located between the conductor shielding layer and the constraint net, the second accommodating portion is located between the constr