B1-level flame-retardant optical cable and manufacturing method thereof

Abstract

The invention discloses a B1-level flame-retardant optical cable and a manufacturing method thereof, and relates to the field of flame-retardant optical cables, the B1-level flame-retardant optical cable comprises an outer sheath, a flame-retardant layer is installed in an inner cavity of the outer sheath, a steel belt is installed in an inner cavity of the flame-retardant layer, an aluminum belt is installed in an inner cavity of the steel belt, and an aluminum belt armor layer is installed in an inner cavity of the aluminum belt. Glass fiber yarn is installed in an inner cavity of the aluminum strip armor layer, the inner cavity of the glass fiber yarn is filled with ointment, a filling assembly and a loose tube are installed in the inner cavity of the glass fiber yarn, and a cushion layer is installed in the center of the inner cavity of the glass fiber yarn. According to the B1-level flame-retardant optical cable and the manufacturing method thereof, the optical cable is mainly used in a service environment with definite requirements on heat released during combustion, a peak value and smoke production in scenes such as railways, buildings and traffic, and the situation that combustion drippings and toxic gas generated in the combustion process cause great threats to escape of personnel and safety of equipment can be effectively avoided.

Description

Technical Field

[0001] The present invention relates to the field of flame-retardant optical cables, and in particular to a B1-class flame-retardant optical cable and a manufacturing method thereof. Background Art

[0002] Optical cable is manufactured to meet optical, mechanical or environmental performance specifications. It is a communication cable assembly that uses one or more optical fibers placed in a sheath as a transmission medium and can be used individually or in groups. The optical cable is mainly composed of optical fiber and plastic protective sheath and plastic outer skin. There is no metal such as gold, silver, copper and aluminum in the optical cable, and it generally has no recycling value. The optical cable is a communication line in which a certain number of optical fibers are arranged in a certain way to form a cable core, which is covered with a sheath and some are also covered with an outer sheath to realize the transmission of optical signals.

[0003] Currently, there are relatively few products that meet the requirements of B1-level flame-retardant optical cables, and the flame-retardant performance of conventional optical cables mostly refers to the "Combustion Test of Electrical Cables and Optical Cables under Flame Conditions" standard. This standard only considers the flame-retardant performance of optical cables, and the sheath material only uses conventional high-flame-retardant materials. After accidental combustion, it will produce dripping matter and toxic gases, posing a greater threat to the escape of personnel and the safety of equipment.

[0004] Therefore, it is necessary to propose a B1-class flame-retardant optical cable and a manufacturing method thereof to solve the above problems. Summary of the invention

[0005] The main purpose of the present invention is to provide a B1-class flame-retardant optical cable and a manufacturing method thereof, which can effectively solve the problems in the background technology.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A B1-class flame-retardant optical cable, comprising an outer sheath, a flame-retardant layer installed in the inner cavity of the outer sheath, a steel belt installed in the inner cavity of the flame-retardant layer, an aluminum belt installed in the inner cavity of the steel belt, an aluminum belt armor layer installed in the inner cavity of the aluminum belt, and glass fiber yarn installed in the inner cavity of the aluminum belt armor layer;

[0008] The inner cavity of the glass fiber yarn is filled with ointment, and a filling component and a loose tube are installed in the inner cavity of the glass fiber yarn;

[0009] A cushion layer is installed in the middle of the inner cavity of the glass fiber yarn.

[0010] Preferably, a first steel wire is installed on the outer wall of the outer sheath, a second steel wire is installed in the inner cavity of the flame retardant layer, an air hole is opened on the outer wall of the second steel wire, a reinforcement layer is installed on the outer wall of the aluminum tape armor layer, and both ends of the reinforcement layer are symmetrically installed on the opposite side of the glass fiber yarn and the aluminum tape, and the aluminum tape armor layer includes a first polyurethane foam layer and a second polyurethane foam layer, the other ends of the first polyurethane foam layer and the second polyurethane foam layer are connected to the reinforcement layer, the inner cavities of the first polyurethane foam layer and the second polyurethane foam layer are filled with composite material fillers, and wavy edges are installed at the connections between the first polyurethane foam layer, the second polyurethane foam layer and the reinforcement layer.

[0011] Preferably, there are two groups of filling components and four groups of loose tubes, a water-blocking yarn is installed in the inner cavity of the loose tube, a connecting nylon is installed on the outer wall of the water-blocking yarn, an inner sheath is installed on the inner wall of the connecting nylon, the inner cavity of the inner sheath is filled with fiber paste, an optical fiber is installed in the inner cavity of the fiber paste, the filling component includes an adaptive expansion filling layer, a silicone rubber layer is installed in the inner cavity of the adaptive expansion filling layer, a desiccant layer is filled in the inner cavity of the silicone rubber layer and the adaptive expansion filling layer, a gradient structure filling layer is installed in the inner cavity of the silicone rubber layer, the adaptive expansion filling layer maintains a relatively stable volume and performance under normal conditions, but when the optical cable is subjected to a certain degree of external force compression or encounters local temperature changes, the filling material can expand adaptively, the desiccant layer is used to absorb water vapor generated inside the optical cable, the silicone rubber layer is used to avoid micro-bending losses to the optical fiber, and can effectively buffer stress when the optical cable is bent or stretched, and the gradient structure filling layer is realized by a multi-layer co-extrusion process, so that the filling components can exert their respective optimized performance at different levels.

[0012] Preferably, a first buffer pad is installed in the inner cavity of the cushion layer, the inner cavity of the first buffer pad is filled with a first asbestos filling layer, an antibacterial layer is installed in the inner cavity of the first buffer pad, a second buffer pad is installed in the inner cavity of the antibacterial layer, the inner cavity of the second buffer pad is filled with a second asbestos filling layer, and a central reinforcement is installed in the middle of the inner cavity of the cushion layer.

[0013] Preferably, the material of the central reinforcement includes but is not limited to FRP, phosphating steel wire, galvanized steel wire, the thickness of the cushion layer is 0.3-3.0 mm, the material of the loose tube includes but is not limited to PP, PC and PBT, the diameter of the first steel wire is 0.2-0.4 mm, and the first steel wire is evenly wrapped around the outer wall of the outer sheath with a pitch of 10-300 mm.

[0014] Preferably, the glass fiber yarn is evenly wrapped around the outer wall of the ointment with a pitch of 500-1000mm, the thickness of the inner sheath is 1-3.5mm, the outer side of the inner sheath is longitudinally wrapped with a double-sided coated steel strip and a first steel wire layer with a diameter of 0.2-0.4mm is evenly wrapped with a pitch of 10-30mm, the thickness of the outer sheath is 1.5-4.0mm, the outer side of the outer sheath is longitudinally wrapped with a double-sided coated steel strip and a second steel wire layer with a diameter of 0.2-0.4mm is evenly wrapped with a pitch of 10-30mm.

[0015] A method for manufacturing a Class B flame-retardant optical cable comprises the following steps:

[0016] S1: Preparation of outer sheath, loose tube and inner sheath, prepare raw materials for preparation, mix the raw materials respectively according to proportion, add stabilizer, lubricant and flame retardant, mix them to obtain uniform material, add the mixed material into extruder, melt the material and extrude it into outer sheath, loose tube and inner sheath of required shape by heating and rotating, cool the extruded outer sheath, loose tube and inner sheath through cold water tank respectively to solidify and keep the shape, use traction equipment to pull the cooled and solidified outer sheath, loose tube and inner sheath to winding device, perform quality inspection on them, including but not limited to appearance, size, mechanical properties and electrical properties, and place them for standby after inspecting the outer wall;

[0017] S2: Preparation of optical fiber, installing the optical fiber into the inner cavity of the inner sheath, filling the remaining space of the inner cavity of the inner sheath with fiber paste, connecting the water-blocking yarn with the inner sheath through the connecting nylon, and installing the loose tube on the outer wall connecting the nylon and the water-blocking yarn, thereby completing the overall preparation of the optical fiber;

[0018] S3: preparing the cushion layer, filling the central reinforcement member in the inner cavity of the second cushion pad, installing the antibacterial layer on the outer wall of the second cushion pad, and installing the first cushion pad on the outer wall of the second cushion pad, thereby completing the preparation of the cushion layer;

[0019] S4: Overall preparation, prepare the first steel wire, outer sheath, flame retardant layer, second steel wire, steel strip, aluminum strip, aluminum strip armor layer, reinforcement layer, glass fiber yarn, and ointment, fill the filling component, loose tube and cushion layer into the inner cavity of the glass fiber yarn, fill the ointment into the remaining space in the inner cavity of the glass fiber yarn, connect the aluminum strip armor layer through the reinforcement layer and install it on the outer wall of the glass fiber yarn, install the aluminum strip on the outer walls of the aluminum strip armor layer and the reinforcement layer, open air holes at both ends of the second steel wire, fill the second steel wire into the inner cavity of the flame retardant layer, install the flame retardant layer on the outer wall of the steel strip, install the steel strip on the outer wall of the aluminum strip, install the outer sheath on the outer wall of the flame retardant layer, and evenly wrap the first steel wire around the outer wall of the outer sheath.

[0020] Compared with the prior art, the present invention provides a B1-class flame-retardant optical cable and a manufacturing method thereof, which has the following beneficial effects:

[0021] 1. This Class B flame-retardant optical cable and its manufacturing method are mainly used in scenarios such as railways, buildings, and transportation, which have clear requirements on the heat released, peak value, and smoke produced during combustion. It can effectively avoid the combustion process. The generation of combustion drips and toxic gases poses a greater threat to the escape of personnel and the safety of equipment.

[0022] 2. The Class B flame-retardant optical cable and its manufacturing method can meet the requirements of standard GB-, and at the same time have good resistance to burning dripping, smoke toxicity, and corrosion. The glass fiber yarn can play a tensile and heat-insulating role, which can slow down the heating of the cable core. The aluminum belt, aluminum belt armor layer and reinforcement layer arranged at the steel belt can prevent the steel belt from expanding due to heat, damaging the outer sheath, and generating dripping. The cushion layer, filling components and inner sheath can play a role of heat insulation and oxygen isolation, effectively reducing the heating of the cable core.

[0023] 3. The Class B flame-retardant optical cable and its manufacturing method can better adapt to harsh environments through the provided filling components, ensure the stability and reliability of optical fiber transmission, and reduce the risk of signal interruption and attenuation. When the optical cable is squeezed to increase the internal pressure or the local temperature, the adaptive expansion filling layer can expand rapidly to fill the tiny gaps caused by external force or temperature changes, maintain the tightness and stability of the internal structure of the optical cable, and prevent the optical fiber from being lost due to displacement or uneven force. Once the external pressure or temperature returns to normal, the filling material will gradually return to its original state and will not have a negative impact on the long-term performance of the optical cable. The aluminum tape armor layer can better withstand the challenges brought by the harsh natural environment, reduce maintenance costs, and improve network stability. In some indoor wiring scenarios where the optical cable needs to be bent frequently, it can also better adapt to bending deformation and reduce damage to the optical fiber. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 It is a schematic diagram of the structure of the optical fiber of the present invention;

[0026] Figure 3 It is a structural schematic diagram of the cushion layer of the present invention;

[0027] Figure 4 It is a schematic diagram of the structure of the aluminum tape armor layer of the present invention;

[0028] Figure 5 It is a structural schematic diagram of the filling component of the present invention.

[0029] In the figure: 1. first steel wire; 2. outer sheath; 3. flame retardant layer; 4. second steel wire; 5. air vent; 6. steel belt; 7. aluminum belt; 8. aluminum belt armor layer; 9. reinforcement layer; 10. glass fiber yarn; 11. paste; 12. filling component; 13. loose tube; 14. water-blocking yarn; 15. connecting nylon; 16. inner sheath; 17. fiber paste; 18. optical fiber; 19. cushion layer; 20. first buffer pad; 21. first asbestos filling layer; 22. antibacterial layer; 23. second asbestos filling layer; 24. second buffer pad; 25. central reinforcement; 26. first polyurethane foam layer; 27. composite material filler; 28. wavy edge; 29. ​​second polyurethane foam layer; 30. adaptive expansion filling layer; 31. desiccant layer; 32. silicone rubber layer; 33. gradient structure filling layer. DETAILED DESCRIPTION

[0030] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0031] like Figure 1-Figure 5As shown, a B1-class flame-retardant optical cable comprises an outer sheath 2, an inner cavity of the outer sheath 2 is installed with a flame-retardant layer 3, an inner cavity of the flame-retardant layer 3 is installed with a steel belt 6, an inner cavity of the steel belt 6 is installed with an aluminum belt 7, an inner cavity of the aluminum belt 7 is installed with an aluminum belt armor layer 8, a glass fiber yarn 10 is installed in the inner cavity of the aluminum belt armor layer 8, the inner cavity of the glass fiber yarn 10 is filled with grease 11, a filling component 12 and a loose tube 13 are installed in the inner cavity of the glass fiber yarn 10, a cushion layer 19 is installed in the middle of the inner cavity of the glass fiber yarn 10, a first steel wire 1 is installed on the outer wall of the outer sheath 2, a second steel wire 4 is installed in the inner cavity of the flame-retardant layer 3, an outer wall of the second steel wire 4 is provided with an air vent 5, a reinforcement layer 9 is installed on the outer wall of the aluminum belt armor layer 8, and both ends of the reinforcement layer 9 are symmetrically installed on the glass fiber On the side opposite to the fiber yarn 10 and the aluminum tape 7, the aluminum tape armor layer 8 includes a first polyurethane foam layer 26 and a second polyurethane foam layer 29, the other ends of the first polyurethane foam layer 26 and the second polyurethane foam layer 29 are connected to the reinforcement layer 9, the inner cavities of the first polyurethane foam layer 26 and the second polyurethane foam layer 29 are filled with a composite material filler 27, and a wavy edge 28 is installed at the connection between the first polyurethane foam layer 26, the second polyurethane foam layer 29 and the reinforcement layer 9. There are two groups of filling components 12, and the filling components 12 include an adaptive expansion filling layer 30, a silicone rubber layer 32 is installed in the inner cavity of the adaptive expansion filling layer 30, and the inner cavities of the silicone rubber layer 32 and the adaptive expansion filling layer 30 are filled with a desiccant layer 31, and the inner cavity of the silicone rubber layer 32 is installed A gradient structure filling layer 33 is installed. The adaptive expansion filling layer 30 maintains a relatively stable volume and performance under normal conditions. However, when the optical cable is subjected to a certain degree of external force or encounters local temperature changes, the filling material can expand adaptively. The desiccant layer 31 is used to absorb the water vapor generated inside the optical cable. The silicone rubber layer 32 is used to avoid micro-bending losses to the optical fiber. At the same time, it can effectively buffer the stress when the optical cable is bent and stretched. The gradient structure filling layer 33 is realized by a multi-layer co-extrusion process, so that the filling components 12 can exert their respective optimized performance at different levels. There are four groups of loose tubes 13. A water-blocking yarn 14 is installed in the inner cavity of the loose tube 13. The outer wall of the water-blocking yarn 14 is installed with a connecting nylon 15, and the inner wall of the connecting nylon 15 is installed with an inner protective The inner cavity of the inner sheath 16 is filled with fiber paste 17, the inner cavity of the fiber paste 17 is installed with an optical fiber 18, the inner cavity of the cushion layer 19 is installed with a first buffer pad 20, the inner cavity of the first buffer pad 20 is filled with a first asbestos filling layer 21, the inner cavity of the first buffer pad 20 is installed with an antibacterial layer 22, the inner cavity of the antibacterial layer 22 is installed with a second buffer pad 24, the inner cavity of the second buffer pad 24 is filled with a second asbestos filling layer 23, a central reinforcement member 25 is installed in the middle of the inner cavity of the cushion layer 19, the material of the central reinforcement member 25 includes but is not limited to FRP, phosphating steel wire, galvanized steel wire, the thickness of the cushion layer 19 is 0.3-3.0mm, the material of the loose tube 13 includes but is not limited to PP, PC and PBT, the diameter of the first steel wire 1 is 0.2-0.4mm, the first steel wire 1 is evenly wrapped around the outer wall of the outer sheath 2 at a pitch of 10-300mm, the glass fiber yarn 10 is evenly wrapped around the outer wall of the paste 11 at a pitch of 500-1000mm, the thickness of the inner sheath 16 is 1-3.5mm, the outer side of the inner sheath 16 is longitudinally wrapped with a double-sided coated steel strip and evenly wrapped with a first steel wire layer with a diameter of 0.2-0.4mm at a pitch of 10-30mm, the thickness of the outer sheath 2 is 1.5-4.0mm, the outer side of the outer sheath 2 is longitudinally wrapped with a double-sided coated steel strip and evenly wrapped with a second steel wire layer with a diameter of 0.2-0.4mm at a pitch of 10-30mm;.

[0032] This optical cable is mainly used in scenarios such as railways, buildings, and transportation that have clear requirements on the heat released, peak value, and smoke produced during combustion. It can effectively avoid the combustion drippings and toxic gases produced during the combustion process, which pose a great threat to the escape of personnel and the safety of equipment. This optical cable can meet the requirements of standard GB31247-2014, and at the same time has a good level of protection against combustion drippings, smoke toxicity, and corrosion. The glass fiber yarn 10 provided can play a tensile and heat-insulating role, and can slow down the heating of the cable core. The aluminum strip 7, aluminum strip armor layer 8, and reinforcement layer 9 provided at the steel strip 6 can prevent the steel strip 6 from expanding due to heat, damaging the outer sheath, and producing drippings. The cushion layer 19, filling component 12, and inner sheath 16 provided can play a role of heat insulation and oxygen isolation, and effectively reduce the heating of the cable core.

[0033] A method for manufacturing a B1-class flame-retardant optical cable comprises the following steps:

[0034] S1: Preparation of the outer sheath 2, the loose tube 13 and the inner sheath 16, preparing raw materials for preparation, mixing the raw materials in proportion, adding a stabilizer, a lubricant and a flame retardant, mixing them to obtain a uniform material, adding the mixed material to an extruder, heating and rotating the material to melt and extrude the material into an outer sheath 2, a loose tube 13 and an inner sheath 16 of a required shape, cooling the extruded outer sheath 2, the loose tube 13 and the inner sheath 16 through a cold water tank respectively to solidify and keep the shape, using a traction device to traction the cooled and solidified outer sheath 2, the loose tube 13 and the inner sheath 16 to a winding device, performing quality inspection on them, including but not limited to appearance, size, mechanical properties and electrical properties, and placing them for standby after the outer wall is inspected;

[0035] S2: Preparation of optical fiber 18, installing optical fiber 18 into the inner cavity of inner sheath 16, filling fiber paste 17 into the remaining space of the inner cavity of inner sheath 16, connecting water-blocking yarn 14 through connecting nylon 15 and connecting to inner sheath 16, installing loose tube 13 on the outer wall connecting nylon 15 and water-blocking yarn 14, thereby completing the preparation of optical fiber 18 as a whole;

[0036] S3: Preparation of the cushion layer 19, filling the central reinforcement 25 in the inner cavity of the second cushion pad 24, installing the antibacterial layer 22 on the outer wall of the second cushion pad 24, and installing the first cushion pad 20 on the outer wall of the second cushion pad 24, thereby completing the preparation of the cushion layer 19;

[0037] S4: Overall preparation, prepare the first steel wire 1, the outer sheath 2, the flame retardant layer 3, the second steel wire 4, the steel belt 6, the aluminum belt 7, the aluminum belt armor layer 8, the reinforcement layer 9, the glass fiber yarn 10, and the paste 11, fill the filling component 12, the loose tube 13 and the cushion layer 19 into the inner cavity of the glass fiber yarn 10, fill the paste 11 into the remaining space in the inner cavity of the glass fiber yarn 10, connect the aluminum belt armor layer 8 through the reinforcement layer 9, and install it on the outer wall of the glass fiber yarn 10, install the aluminum belt 7 on the outer walls of the aluminum belt armor layer 8 and the reinforcement layer 9, open air holes 5 at both ends of the second steel wire 4, fill the second steel wire 4 into the inner cavity of the flame retardant layer 3, install the flame retardant layer 3 on the outer wall of the steel belt 6, install the steel belt 6 on the outer wall of the aluminum belt 7, install the outer sheath 2 on the outer wall of the flame retardant layer 3, and evenly wrap the first steel wire 1 around the outer wall of the outer sheath 2.

[0038] Embodiment 1:

[0039] A method for manufacturing a B1-class flame-retardant optical cable comprises the following steps:

[0040] S1: Preparation of an outer sheath 2, a loose tube 13 and an inner sheath 16, wherein the outer sheath 2 is made of PP, the loose tube 13 is made of PP, and the inner sheath 16 is made of PP, raw materials for preparation are prepared, the raw materials are mixed in proportion, and a stabilizer, a lubricant and a flame retardant are added, wherein the raw materials of the outer sheath 2 include 90 parts of PP, 3 parts of stability, 3 parts of lubricant and 4 parts of flame retardant by mass; the raw materials of the loose tube 13 include 85 parts of PP, 3 parts of stability, 2 parts of lubricant and 10 parts of flame retardant by mass; the raw materials of the inner sheath 16 include 90 parts of PP, 3 parts of stability, 3 parts of lubricant and 4 parts of flame retardant by mass;

[0041] After mixing, a uniform material is obtained, and the mixed material is added to an extruder. The material is melted and extruded into an outer sheath 2, a loose tube 13 and an inner sheath 16 that meet the required shapes by heating and rotating. The extruded outer sheath 2, the loose tube 13 and the inner sheath 16 are cooled by a cold water tank respectively to solidify and keep the shape. The cooled and solidified outer sheath 2, the loose tube 13 and the inner sheath 16 are pulled to a winding device by a pulling device, and the quality is tested, including but not limited to appearance, size, mechanical properties and electrical properties. After the outer wall is tested, they are placed for standby use;

[0042] S2: Preparation of optical fiber 18, installing optical fiber 18 into the inner cavity of inner sheath 16, filling fiber paste 17 into the remaining space of the inner cavity of inner sheath 16, connecting water-blocking yarn 14 through connecting nylon 15 and connecting to inner sheath 16, installing loose tube 13 on the outer wall connecting nylon 15 and water-blocking yarn 14, thereby completing the preparation of optical fiber 18 as a whole;

[0043] S3: Preparation of the cushion layer 19. The central reinforcement member 25 is made of phosphated steel wire. The central reinforcement member 25 is filled in the inner cavity of the second cushion pad 24. The antibacterial layer 22 is installed on the outer wall of the second cushion pad 24. The first cushion pad 20 is installed on the outer wall of the second cushion pad 24. Thus, the preparation of the cushion layer 19 is completed.

[0044] S4: Overall preparation, prepare the first steel wire 1, the outer sheath 2, the flame retardant layer 3, the second steel wire 4, the steel belt 6, the aluminum belt 7, the aluminum belt armor layer 8, the reinforcement layer 9, the glass fiber yarn 10, and the paste 11, fill the filling component 12, the loose tube 13 and the cushion layer 19 into the inner cavity of the glass fiber yarn 10, fill the paste 11 into the remaining space in the inner cavity of the glass fiber yarn 10, connect the aluminum belt armor layer 8 through the reinforcement layer 9, and install it on the outer wall of the glass fiber yarn 10, install the aluminum belt 7 on the outer walls of the aluminum belt armor layer 8 and the reinforcement layer 9, open air holes 5 at both ends of the second steel wire 4, fill the second steel wire 4 into the inner cavity of the flame retardant layer 3, install the flame retardant layer 3 on the outer wall of the steel belt 6, install the steel belt 6 on the outer wall of the aluminum belt 7, install the outer sheath 2 on the outer wall of the flame retardant layer 3, and evenly wrap the first steel wire 1 around the outer wall of the outer sheath 2. Specific embodiment 2:

[0046] A method for manufacturing a B1-class flame-retardant optical cable comprises the following steps:

[0047] S1: Preparation of an outer sheath 2, a loose tube 13 and an inner sheath 16, wherein the outer sheath 2 is made of PBT, the loose tube 13 is made of PBT, and the inner sheath 16 is made of PBT, raw materials for preparation are prepared, the raw materials are mixed in proportion, and a stabilizer, a lubricant and a flame retardant are added, wherein the raw materials of the outer sheath 2 include 90 parts of PBT, 3 parts of stability, 3 parts of lubricant and 4 parts of flame retardant by mass; the raw materials of the loose tube 13 include 85 parts of PBT, 3 parts of stability, 2 parts of lubricant and 10 parts of flame retardant by mass; the raw materials of the inner sheath 16 include 90 parts of PBT, 3 parts of stability, 3 parts of lubricant and 4 parts of flame retardant by mass;

[0048] After mixing, a uniform material is obtained, and the mixed material is added to an extruder. The material is melted and extruded into an outer sheath 2, a loose tube 13 and an inner sheath 16 that meet the required shapes by heating and rotating. The extruded outer sheath 2, the loose tube 13 and the inner sheath 16 are cooled by a cold water tank respectively to solidify and keep the shape. The cooled and solidified outer sheath 2, the loose tube 13 and the inner sheath 16 are pulled to a winding device by a pulling device, and the quality is tested, including but not limited to appearance, size, mechanical properties and electrical properties. After the outer wall is tested, they are placed for standby use;

[0049] S2: Preparation of optical fiber 18, installing optical fiber 18 into the inner cavity of inner sheath 16, filling fiber paste 17 into the remaining space of the inner cavity of inner sheath 16, connecting water-blocking yarn 14 through connecting nylon 15 and connecting to inner sheath 16, installing loose tube 13 on the outer wall connecting nylon 15 and water-blocking yarn 14, thereby completing the preparation of optical fiber 18 as a whole;

[0050] S3: Preparation of the cushion layer 19. The central reinforcement member 25 is made of galvanized steel wire. The central reinforcement member 25 is filled in the inner cavity of the second cushion pad 24. The antibacterial layer 22 is installed on the outer wall of the second cushion pad 24. The first cushion pad 20 is installed on the outer wall of the second cushion pad 24. Thus, the preparation of the cushion layer 19 is completed.

[0051] S4: Overall preparation, prepare the first steel wire 1, the outer sheath 2, the flame retardant layer 3, the second steel wire 4, the steel belt 6, the aluminum belt 7, the aluminum belt armor layer 8, the reinforcement layer 9, the glass fiber yarn 10, and the paste 11, fill the filling component 12, the loose tube 13 and the cushion layer 19 into the inner cavity of the glass fiber yarn 10, fill the paste 11 into the remaining space in the inner cavity of the glass fiber yarn 10, connect the aluminum belt armor layer 8 through the reinforcement layer 9, and install it on the outer wall of the glass fiber yarn 10, install the aluminum belt 7 on the outer walls of the aluminum belt armor layer 8 and the reinforcement layer 9, open air holes 5 at both ends of the second steel wire 4, fill the second steel wire 4 into the inner cavity of the flame retardant layer 3, install the flame retardant layer 3 on the outer wall of the steel belt 6, install the steel belt 6 on the outer wall of the aluminum belt 7, install the outer sheath 2 on the outer wall of the flame retardant layer 3, and evenly wrap the first steel wire 1 around the outer wall of the outer sheath 2.

[0052] The flame-retardant optical cable prepared in the present application is compared with the flame-retardant optical cable in the prior art in terms of performance, wherein the flame-retardant optical cable prepared in the present application is recorded as Examples 1-2, and the flame-retardant optical cable in the prior art is recorded as Comparative Example 1. The following is a comparison table:

[0053]

[0054]

[0055] It can be seen that the flame-retardant optical cable prepared in the present application has a higher limiting oxygen index, elongation at break and peeling force, and cracks only at a lower temperature, indicating that the flame-retardant optical cable prepared in the present application has significantly improved flame retardancy, toughness, peeling strength and impact resistance.

[0056] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A Class B1 flame-retardant optical cable, comprising an outer sheath (2), characterized in that: The inner cavity of the outer sheath (2) is installed with a flame retardant layer (3), the inner cavity of the flame retardant layer (3) is installed with a steel belt (6), the inner cavity of the steel belt (6) is installed with an aluminum belt (7), the inner cavity of the aluminum belt (7) is installed with an aluminum belt armor layer (8), and the inner cavity of the aluminum belt armor layer (8) is installed with a glass fiber yarn (10); The inner cavity of the glass fiber yarn (10) is filled with grease (11), and a filling component (12) and a loose tube (13) are installed in the inner cavity of the glass fiber yarn (10); A cushion layer (19) is installed in the middle of the inner cavity of the glass fiber yarn (10).

2. The B1-class flame-retardant optical cable according to claim 1, characterized in that: The outer wall of the outer sheath (2) is installed with a first steel wire (1), the inner cavity of the flame retardant layer (3) is installed with a second steel wire (4), the outer wall of the second steel wire (4) is provided with an air hole (5), the outer wall of the aluminum tape armor layer (8) is installed with a reinforcement layer (9), the two ends of the reinforcement layer (9) are symmetrically installed on the opposite side of the glass fiber yarn (10) and the aluminum tape (7), the aluminum tape armor layer (8) comprises a first polyurethane foam layer (26) and a second polyurethane foam layer (29), the other ends of the first polyurethane foam layer (26) and the second polyurethane foam layer (29) are connected to the reinforcement layer (9), the inner cavities of the first polyurethane foam layer (26) and the second polyurethane foam layer (29) are filled with a composite material filler (27), and the connection between the first polyurethane foam layer (26), the second polyurethane foam layer (29) and the reinforcement layer (9) is provided with a wavy edge (28).

3. The B1-class flame-retardant optical cable according to claim 1, characterized in that: The filling components (12) have two groups, and the loose tubes (13) have four groups. A water-blocking yarn (14) is installed in the inner cavity of the loose tubes (13). A connecting nylon (15) is installed on the outer wall of the water-blocking yarn (14). An inner sheath (16) is installed on the inner wall of the connecting nylon (15). The inner cavity of the inner sheath (16) is filled with fiber paste (17). An optical fiber (18) is installed in the inner cavity of the fiber paste (17). The filling components (12) include an adaptive expansion filling layer (30). A silicone rubber layer (32) is installed in the inner cavity of the adaptive expansion filling layer (30). The inner cavities of the silicone rubber layer (32) and the adaptive expansion filling layer (30) are filled with dry The silicone rubber layer (32) is provided with a gradient structure filling layer (33) in the inner cavity of the silicone rubber layer (32). The adaptive expansion filling layer (30) maintains a relatively stable volume and performance under normal conditions, but when the optical cable is subjected to a certain degree of external force compression or encounters local temperature changes, the filling material can expand adaptively. The desiccant layer (31) is used to absorb water vapor generated inside the optical cable. The silicone rubber layer (32) is used to avoid microbending losses on the optical fiber and can effectively buffer stress when the optical cable is bent or stretched. The gradient structure filling layer (33) is realized by a multi-layer co-extrusion process, so that the filling components (12) can exert their respective optimized performance at different levels.

4. The B1-class flame-retardant optical cable according to claim 1, characterized in that: A first buffer pad (20) is installed in the inner cavity of the cushion layer (19), the inner cavity of the first buffer pad (20) is filled with a first asbestos filling layer (21), an antibacterial layer (22) is installed in the inner cavity of the first buffer pad (20), a second buffer pad (24) is installed in the inner cavity of the antibacterial layer (22), the inner cavity of the second buffer pad (24) is filled with a second asbestos filling layer (23), and a central reinforcement member (25) is installed in the middle of the inner cavity of the cushion layer (19).

5. The B1-class flame-retardant optical cable according to claim 1, characterized in that: The material of the central reinforcement (25) includes but is not limited to FRP, phosphated steel wire, galvanized steel wire, the thickness of the cushion layer (19) is 0.3-3.0 mm, the material of the loose tube (13) includes but is not limited to PP, PC and PBT, the diameter of the first steel wire (1) is 0.2-0.4 mm, and the first steel wire (1) is evenly wrapped around the outer wall of the outer sheath (2) with a pitch of 10-300 mm.

6. The B1-class flame-retardant optical cable according to claim 1, characterized in that: The glass fiber yarn (10) is evenly wrapped around the outer wall of the paste (11) at a pitch of 500-1000mm, the thickness of the inner sheath (16) is 1-3.5mm, the outer side of the inner sheath (16) is longitudinally wrapped with a double-sided coated steel strip and a first steel wire layer with a diameter of 0.2-0.4mm is evenly wrapped at a pitch of 10-30mm, the thickness of the outer sheath (2) is 1.5-4.0mm, the outer side of the outer sheath (2) is longitudinally wrapped with a double-sided coated steel strip and a second steel wire layer with a diameter of 0.2-0.4mm is evenly wrapped at a pitch of 10-30mm.

7. The method for manufacturing a Class B1 flame-retardant optical cable according to claim 1, characterized in that: The steps include: S1: Preparation of an outer sheath (2), a loose tube (13) and an inner sheath (16), preparing raw materials for preparation, mixing the raw materials in proportion, adding a stabilizer, a lubricant and a flame retardant, mixing the raw materials to obtain a uniform material, adding the mixed material to an extruder, heating and rotating the material to melt and extrude the material into an outer sheath (2), a loose tube (13) and an inner sheath (16) of a required shape, cooling the extruded outer sheath (2), loose tube (13) and inner sheath (16) through a cold water tank respectively to solidify and maintain the shape, using a traction device to traction the cooled and solidified outer sheath (2), loose tube (13) and inner sheath (16) to a winding device, performing quality inspection on the outer sheath, including but not limited to appearance, size, mechanical properties and electrical properties, and placing the outer sheath for standby use after inspecting the outer wall; S2: Preparation of the optical fiber (18), installing the optical fiber (18) into the inner cavity of the inner sheath (16), filling the fiber paste (17) into the remaining space in the inner cavity of the inner sheath (16), connecting the water-blocking yarn (14) through the connecting nylon (15) and connecting it to the inner sheath (16), installing the loose tube (13) on the outer wall of the connecting nylon (15) and the water-blocking yarn (14), thereby completing the preparation of the entire optical fiber (18); S3: Preparation of the cushion layer (19), filling the central reinforcement member (25) in the inner cavity of the second cushion pad (24), installing the antibacterial layer (22) on the outer wall of the second cushion pad (24), and installing the first cushion pad (20) on the outer wall of the second cushion pad (24), thereby completing the preparation of the cushion layer (19); S4: overall preparation, preparing the first steel wire (1), the outer sheath (2), the flame retardant layer (3), the second steel wire (4), the steel tape (6), the aluminum tape (7), the aluminum tape armor layer (8), the reinforcement layer (9), the glass fiber yarn (10), the grease (11), filling the filling component (12), the loose tube (13) and the cushion layer (19) into the inner cavity of the glass fiber yarn (10), filling the grease (11) into the remaining space in the inner cavity of the glass fiber yarn (10), and inserting the aluminum tape armor layer (8) through the reinforcement layer (9) The second steel wire (4) is connected and installed on the outer wall of the glass fiber yarn (10), the aluminum tape (7) is installed on the outer wall of the aluminum tape armor layer (8) and the reinforcement layer (9), air holes (5) are opened at both ends of the second steel wire (4), the second steel wire (4) is filled into the inner cavity of the flame retardant layer (3), the flame retardant layer (3) is installed on the outer wall of the steel tape (6), the steel tape (6) is installed on the outer wall of the aluminum tape (7), the outer sheath (2) is installed on the outer wall of the flame retardant layer (3), and the first steel wire (1) is evenly wrapped around the outer wall of the outer sheath (2).

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