High-temperature-resistant loose tube optical cable for aviation and preparation method thereof

Abstract

The application relates to a method for preparing a high-temperature-resistant loose-jacket optical cable for aviation, and belongs to the technical field of optical cables. The method comprises a cable core, the outer side of the cable core is sequentially provided with a buffer layer and a sheath layer, the buffer layer is composed of polytetrafluoroethylene belts which are spirally glued to the outer end of the cable core, one end of the polytetrafluoroethylene belt towards the cable core is provided with an expansion layer, and the expansion layer can be heated and expanded and tightly adhered between the sheath layer and the cable core. The buffer layer is glued to the outer side end of the cable core, the combination strength between the buffer layer and the cable core is improved, the buffer layer is not prone to loosening, and the expansion layer can be heated and expanded. After extrusion, the expansion layer is heated and expanded, the peripheral sheath layer formed by the extrusion material is expanded, and the combination strength between the adjacent sheath layers is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of optical cables, and particularly relates to a high-temperature-resistant loose-jacket optical cable for aviation and a preparation method. BACKGROUND

[0002] An optical cable is a communication line for optical signal transmission, is usually installed in various environments, and is widely applied, and has high requirements on temperature resistance and quality.

[0003] In the prior art, an application with the publication number CN104777572A and the patent name of high-temperature-resistant loose-jacket optical cable for aviation and a preparation method is disclosed, which specifically discloses that the optical cable comprises a peripheral optical fiber core 1, a coating layer 2 surrounding the optical fiber core 1, a polytetrafluoroethylene (PTFE) tape-wrapped buffer layer 3 surrounding the coating layer 2, a polyether ether ketone (PEEK) loose-jacket layer 4 surrounding the PTFE tape-wrapped buffer layer 3, an aramid fiber reinforcing layer 5 surrounding the PEEK loose-jacket layer 4, and an ethylene tetrafluoroethylene (ETFE) sheath layer 6 surrounding the aramid fiber reinforcing layer 5. The optical cable in the above scheme has the characteristics of long-term resistance to high and low temperatures of-55 DEG C to +125 DEG C, bending resistance, compression resistance, aging resistance, long service life, corrosion resistance, salt mist resistance, mold resistance, humidity resistance, high flame resistance, and the like, can provide high-reliability services in harsh environments, and is suitable for high-speed signal transmission in aerospace, electronics, and special airborne environmental conditions.

[0004] In the prior art, when the optical cable is processed, the buffer layer of the optical cable is single-helically wound by using an ordinary wrapping machine to wrap polyether ether ketone resin, and the buffer layer is fixed only by traction force, so that the buffer layer formed in this way is prone to displacement and loosening due to low bonding strength between the buffer layer and the cable core, thereby affecting the effect of the buffer layer. Therefore, the high-temperature-resistant loose-jacket optical cable for aviation and the preparation method are proposed to solve the above problems. SUMMARY

[0005] Technical problems solved

[0006] In view of the above shortcomings of the prior art, the application provides the high-temperature-resistant loose-jacket optical cable for aviation and the preparation method, which can effectively solve the problem that the buffer layer is prone to loosening and finally leads to poor performance of the optical cable when the buffer layer is wound in the prior art.

[0007] Technical scheme

[0008] To achieve the above object, the application is implemented by the following technical scheme:

[0009] The application provides a high-temperature-resistant loose tube optical cable for aviation, which comprises a cable core, a buffer layer and a sheath layer arranged on the outer side of the cable core in sequence, wherein the buffer layer is composed of polytetrafluoroethylene tapes which are spirally glued to the outer end of the cable core, and one end of the polytetrafluoroethylene tape is provided with an expansion layer, and the expansion layer can be expanded by heat and closely fit between the buffer layer (2) and the cable core.

[0010] The application further provides a method for preparing the high-temperature-resistant loose tube optical cable for aviation, which comprises the following steps:

[0011] Step 1: guiding and pulling the cable core along the processing sequence direction on the rack by a pulling device, and sequentially passing through a sleeving station, an extrusion station, an extrusion molding station and a cooling station arranged on the rack;

[0012] Step 2: when the cable core passes through the sleeving station, the winding machine on the sleeving station winds and bonds the polytetrafluoroethylene tape on the outer end of the cable core;

[0013] Step 3: extruding the edge of the polytetrafluoroethylene tape bonded on the outer end of the cable core by the extrusion station;

[0014] Step 4: forming a sheath layer on the outer side of the buffer layer by the extrusion molding station, and cooling and treating the sheath layer by the cooling station.

[0015] Further, the winding machine comprises a winding disc which is rotationally installed on the rack and coaxially arranged on the outer end of the cable core, wherein the winding disc is provided with a winding disc, the winding disc is provided with the polytetrafluoroethylene tape wound in a roll shape, and the polytetrafluoroethylene tape moves in a circumferential direction on the outer end of the cable core with the rotation of the winding disc, so that the polytetrafluoroethylene tape is spirally sleeved on the outer end of the cable core.

[0016] Further, the winding disc is provided with two winding discs, each winding disc is arranged obliquely to the cable core, and the distance between the two winding discs and the winding disc is not equal.

[0017] Further, the middle part of the polytetrafluoroethylene tape is provided with a groove, the two sides of the groove are adhesive surfaces, a flat air bag is embedded in the groove, and the flat air bag is glued in the groove and is in the same plane as the adhesive surface of the polytetrafluoroethylene tape.

[0018] Further, the flat air bag is filled with carbon dioxide gas.

[0019] Further, the spiral pitches of the polytetrafluoroethylene tapes on the two winding discs are the same, the polytetrafluoroethylene tape on the winding disc away from the winding disc is wound around the middle part of the spiral pitch formed by the polytetrafluoroethylene tape on the other winding disc, and the spiral pitch formed by the polytetrafluoroethylene tape is smaller than the width of the polytetrafluoroethylene tape.

[0020] Further, the extrusion station comprises hot pressing blocks, the hot pressing blocks are arranged on the outer end of the cable core in a plurality of and circumferential arrangement, and the hot pressing blocks are in the shape of arc blocks, each of which is provided with a convex ring on the two sides along the axial direction of the cable core, the convex ring protrudes towards the cable core, and intersects with the moving path of the polytetrafluoroethylene tape spiral outer end wound around the protruding polytetrafluoroethylene tape spiral outer end of the cable core, and an electric heating plate is arranged between the two convex rings, the distance between the electric heating plate and the outer end of the cable core is less than the distance between the convex ring and the cable core, and the electric heating plate does not intersect with the moving path of the polytetrafluoroethylene tape spiral outer end wound around the protruding polytetrafluoroethylene tape spiral outer end of the cable core.

[0021] Further, each of the hot pressing blocks can elastically slide along the radial direction of the cable core.

[0022] Further, the side ends of the adjacent convex rings are attached, and the convex ring is made of heat-resistant rubber material.

[0023] Beneficial effects

[0024] The technical scheme provided by the present application has the following beneficial effects compared with the known prior art:

[0025] The present application fixes the buffer layer on the outer end of the cable core in a glue-solidified manner, improves the bonding strength between the buffer layer and the cable core, and is not easy to loosen. In addition, the expansion layer can be expanded by heat, and after extrusion, the expansion layer can expand by heat to expand the outer sheath layer formed by the extrusion material, thereby improving the bonding strength between the adjacent sheath layers. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creating any creative labor.

[0027] Figure 1 The figure is a schematic diagram of the optical cable preparation method in the embodiment of the present application;

[0028] Figure 2 The figure is a schematic diagram of the main structure of the optical cable preparation in the embodiment of the present application;

[0029] Figure 3 The figure is a front view schematic diagram of the main structure of the optical cable preparation in the embodiment of the present application;

[0030] Figure 4 The figure is a top view schematic diagram of the main structure of the optical cable preparation in the embodiment of the present application;

[0031] Figure 5 The figure is a schematic diagram of the side view cross-sectional structure of the optical cable in the embodiment of the present application;

[0032] Figure 6 Figure 3 is a schematic view of a partial cross-section of a ring block structure in an embodiment of the present application;

[0033] Figure 7 Figure 4 is a schematic view of a hot press block structure in an embodiment of the present application;

[0034] Figure 8 Figure 5 is a schematic view of a cross-section of a polytetrafluoroethylene tape in an embodiment of the present application;

[0035] Figure 9 Figure 6 is a schematic view of a double-layered sleeve winding structure of a polytetrafluoroethylene tape in an embodiment of the present application.

[0036] The figure marks: 1, cable core; 2, buffer layer; 21, polytetrafluoroethylene tape; 211, groove; 212, flat air bag; 22, expansion layer; 3, sheath layer; 4, rack; 41, winding machine; 411, winding disc; 412, winding disc; 5, sleeve winding station; 6, extrusion station; 61, hot press block; 611, convex ring; 612, electric heating plate; 62, ring block; 7, extrusion station; 71, hot lamp; 8, cooling station. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application.

[0038] In the description of the present application, unless otherwise explicitly specified and limited, the terms "connected", "connected", "fixed" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0039] In the present application, unless otherwise explicitly specified and limited, the "upper" or "lower" of the first feature to the second feature can include the direct contact of the first and second features, or can include the contact of the first and second features through another feature between them. Moreover, the "upper", "upper" and "upper" of the first feature to the second feature include the vertical direction of the first feature above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "lower", "lower" and "lower" of the first feature to the second feature include the vertical direction of the first feature below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0040] In the description of the embodiments, the terms "upper", "lower", "left", "right", and the like, orientation or positional relationships are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used to distinguish in the description, and have no special meaning.

[0041] The application will be further described below in conjunction with the embodiments.

[0042] Embodiment: For optical cables, the better the performance of the optical cable, the longer the service life, and the heat insulation performance and protection performance of the optical cable are reflected in the structures such as the buffer layer and the loose sleeve layer provided outside the cable core. The heat insulation, pressure resistance and other characteristics of these different structures give the optical cable excellent effects.

[0043] However, in the processing process of the optical cable in the prior art, when the buffer layer is sleeved on the cable core, the buffer layer is prone to looseness, which causes the inner part of the sheath layer to be not tight enough, air can circulate, heat can flow due to the communication of air, and to some extent, the pressure resistance of the optical cable is also weakened.

[0044] Therefore, the present application proposes an aviation high-temperature-resistant loose-sleeve optical cable to solve such practical problems. Instead of directly winding a single layer of a buffer layer formed by a polytetrafluoroethylene 21 on the outer end of the cable core, two staggered polytetrafluoroethylene tapes 21 are used for winding, and unlike the traditional technology of directly pulling the winding by traction, a glue layer is provided on the end face of the polytetrafluoroethylene tape 21, which is directly adhered to the outer end of the cable core 1 during winding, thereby improving the bonding strength between the cable core 1 and the polytetrafluoroethylene tape 21, and preventing looseness caused by the transmission process of the cable core 1.

[0045] Specifically, referring to the accompanying Figures 1-9 The aviation high-temperature-resistant loose-sleeve optical cable in the present application comprises a cable core 1, a buffer layer 2 and a sheath layer 3 are sequentially arranged on the outer side of the cable core 1, the buffer layer 2 is composed of a polytetrafluoroethylene tape 21 spirally glued to the outer end of the cable core 1, and one end of the polytetrafluoroethylene tape 21 facing the cable core 1 is provided with an expansion layer 22, which can be expanded by heat and tightly fit between the buffer layer 2 and the cable core 1.

[0046] The present application further provides a method for preparing the aviation high-temperature-resistant loose-sleeve optical cable, comprising the following steps:

[0047] Step 1: guiding and pulling the cable core 1 along the processing sequence direction on the rack 4 by a pulling device, and sequentially passing through the sleeve winding station 5, the extrusion station 6, the extrusion station 7 and the cooling station 8 arranged on the rack 4;

[0048] Step 2: When the cable core 1 passes through the wrapping station 5, the wrapping machine 41 on the wrapping station 5 wraps and bonds the polytetrafluoroethylene tape 21 on the outer end of the cable core 1;

[0049] Step 3: The edges of the polytetrafluoroethylene tape 21 bonded on the outer end of the cable core 1 are extruded by the extrusion station 6;

[0050] Step 4: A sheath layer 3 is formed on the outer side of the buffer layer 2 by the extrusion station 7, and the sheath layer 3 is cooled and treated by the cooling station 8.

[0051] It is worth noting that the steps shown in the present scheme are not completely shown, and the cable core 1 needs to be bent before being wrapped, and the outer side of the cable core 1 needs to be coated, which are all prior art and are not shown in detail in the present case. The figure is limited to the present scheme.

[0052] Specifically, the rack 4 is provided with a rotatable wrapping disc 411, and the driving mode is various. In the present case, the rear side of the wrapping disc 411 is driven to rotate by a belt, which is a well-known technology and is not limited in detail. The wrapping disc 411 is disc-shaped and has a through hole in the middle. The wrapping disc 411 is coaxially arranged on the outer end of the cable core 1, that is, the cable core 1 passes through the through hole for guidance. The way of pulling the cable core 1 is a prior art and is not described in detail.

[0053] The wrapping disc 411 is provided with a winding disc 412, and the winding disc 412 is provided with a polytetrafluoroethylene tape 21 wound in a roll. The polytetrafluoroethylene tape 21 is used as a protective layer for the outer end of the cable core 1 due to its excellent high and low temperature resistance, electrical insulation, chemical inertness, low friction coefficient, and non-stickiness in a wide temperature range (-260 to 260°C).

[0054] Since the wrapping disc 411 rotates and the winding disc 412 is inclinedly arranged between the outer edge of the wrapping disc 411 and the center of the wrapping disc 411, the polytetrafluoroethylene tape 21 on the winding disc 412 moves circumferentially on the outer end of the cable core 1 with the rotation of the wrapping disc 411 during the transmission of the cable core 1, and the polytetrafluoroethylene tape 21 is spirally wrapped on the outer end of the cable core 1, and the formed spiral buffer layer has a certain pitch.

[0055] In the present scheme, in order to further improve the buffering effect of the buffer layer 2, the winding disc 412 is provided with two winding discs 412, each winding disc 412 is inclinedly arranged with the cable core 1, the distance between the two winding discs 412 and the wrapping disc 411 is not equal, the distance between the two winding discs 412 and the center of the wrapping disc 411 is equal, and the center is symmetrically distributed.

[0056] Thus, during the transmission of the cable core 1 and the rotation of the winding disc 411, two PTFE tapes 21 will be presented, and the winding disc 412 close to the winding disc 411 plays a major role in winding and "precedes" the other PTFE tape 21 to be wound on the cable core 1, and the winding disc 412 away from the winding disc 411 further winds on the basis of the spiral tape formed by the previous PTFE tape 21.

[0057] In this case, the spiral pitches formed by the PTFE tapes 21 on the two winding discs 412 are the same, and the PTFE tape 21 on the winding disc 412 away from the winding disc 411 is wound towards the middle of the spiral pitch formed by the PTFE tape 21 on the other winding disc 412, and the spiral pitch formed by the PTFE tape 21 is smaller than the width of the PTFE tape 21.

[0058] That is, when the two winding discs 412 work together, the spiral formed by the subsequent PTFE tape 21 will form a new spiral turn in the middle of the pitch of the previous PTFE tape 21, and a spiral tape is formed by multiple spiral turns. It is worth noting that the two side edges of the subsequent PTFE tape 21 intersect with the side ends of the previous PTFE tape 21, that is, they are adhered to the end face of the previous PTFE tape 21.

[0059] When the subsequent extrusion process starts, a protective layer will be formed on the outside of the PTFE tape 21 by the extruded semi-fluid material. The extruder is a prior art, and the specific extrusion process is not described in detail.

[0060] And the middle part of the PTFE tape 21 is provided with a groove 211, and the two sides of the groove 211 are adhesive surfaces. A flat air bag 212 is embedded in the groove 211, and the flat air bag 212 is adhered in the groove 211 and is in the same plane as the adhesive surface of the PTFE tape 21, and the flat air bag 212 is filled with carbon dioxide gas. The thermal conductivity of carbon dioxide is only 0.01179, which further improves the influence of external environmental factors on the cable core 1, and carbon dioxide will expand when heated.

[0061] After extrusion, the buffer layer 2 will be subjected to high heat, and a heat lamp 71 is provided between the cooling station 8 and the extrusion station 7, the heat lamp 71 is provided with four lamps arranged circumferentially on the outside of the cable core 1, and each lamp faces the cable core 1. At this time, the carbon dioxide in the buffer layer 2 will begin to expand to a certain volume. Due to the characteristics of extrusion, when the cable core 1 passes through the extrusion station 7 for 3-5 seconds, the extrusion material has not completely adhered to the outer end of the cable core 1, but is in the shape of a truncated cone. It can be regarded as "the cable core 1 moves by itself, pulling out a part of the extrusion material, and the adhesion between the extrusion material and the cable core 1 at this time is not high. Due to the heat of the extrusion material and the irradiation of the heat lamp 71, the carbon dioxide in the buffer layer 2 expands and bulges, increasing the bonding area and efficiency between the extrusion material layer and the cable core 1. Usually, after extrusion, a sheath layer 3 needs to be sleeved (the sheath layer 3 is mostly also extruded to realize, which is a prior art, and the present case and the drawings do not show it. Such a way avoids unevenness of the extrusion material layer, so that the bonding between the sheath layer 3 is more closely.

[0062] In the present scheme, in order to ensure the winding effect of the polytetrafluoroethylene tape 21, and also to avoid the sticking of the polytetrafluoroethylene tape 21 due to the pulling of the polytetrafluoroethylene tape 21, the small offset caused by gravity or inertial force forms a wrinkle, in the present scheme, before extrusion, the buffer layer 2 is extruded, especially the adhesive part of the last polytetrafluoroethylene tape 21 is pressed. Since the last polytetrafluoroethylene tape 21 is adhered between the two coils of the previous polytetrafluoroethylene tape 21, it has a certain intersection area, so it has a certain thickness. In the present scheme, by extruding and heating at the same time, the adhesive surface of the last polytetrafluoroethylene tape 21 is adhered more tightly, and the carbon dioxide in the flat air bag 212 is also preliminarily heated.

[0063] Specifically, the extrusion station 6 has a ring block 62, the ring block 62 is internally provided with a cavity, and six hot pressing blocks 61 are arranged in the cavity and are circumferentially arranged on the outer end of the cable core 1 and can move radially along the ring block 62. Each hot pressing block 61 is in the shape of an arc block, and a convex ring 611 is arranged on each of the two sides of the hot pressing block 61 in the axial direction of the cable core 1. The convex ring 611 protrudes towards the cable core 1 and intersects with the movement path of the outer end of the polytetrafluoroethylene tape 21 spirally wound on the protruding outer end of the cable core 1. An electric heating plate 612 is arranged between the two convex rings 611, the distance between the electric heating plate 612 and the outer end of the cable core 1 is less than the distance between the convex ring 611 and the cable core 1, and the electric heating plate 612 does not intersect with the movement path of the outer end of the polytetrafluoroethylene tape 21 spirally wound on the protruding outer end of the cable core 1, and the side ends of adjacent convex rings 611 are in close contact, and the convex ring 611 is made of heat-resistant rubber material. The convex ring 611 can greatly press the polytetrafluoroethylene tape 21 covering part on the outer end of the cable core 1. Furthermore, a spring is arranged between each hot pressing block 61 and the ring block 62, the friction between adjacent convex rings 611 is small, and the gap is small, which is much smaller than the force of the spring, so that the hot pressing block 61 can elastically slide in the radial direction of the cable core 1. The electric heating plate 612 realizes power on and power off through this movement process, which is prior art in the electric heating field, and will not be described in detail.

[0064] When the convex ring 611 moves on the previous polytetrafluoroethylene tape 21, the width of the convex ring 611 in the present case is less than the width of the polytetrafluoroethylene tape 21, so that it will not move, and the electric heating plate 612 is not triggered, and the electric heating plate 612 in the six convex rings 611 is independently installed. When any one of the convex rings 611 contacts the next polytetrafluoroethylene tape 21, the next polytetrafluoroethylene tape 21 is "covered" on the previous polytetrafluoroethylene tape 21, and the covered part has a certain thickness. The longer the electric heating plate 612 is used, the higher the temperature. Therefore, in combination with the above features, the electric heating plate 612 is intermittently turned on and off, i.e. the flat air bag 212 starts to move and triggers the electric heating plate 612 to work. The electric heating plate 612 emits a certain temperature to preheat the flat air bag 212 in the next polytetrafluoroethylene tape 21. When the electric heating plate 612 stops working, the flat air bag 212 in the "bottom layer" is preheated by the residual heat. The purpose of preheating is only to slightly increase the temperature of carbon dioxide, which is not the main source of expansion. Even if the flat air bags 212 in the two polytetrafluoroethylene tapes 21 have different heating, the influence is not great.

[0065] When the convex ring 611 abuts against the covering part, it is extruded towards the covering part to improve the bonding effect.

[0066] It is worth noting that the cooling station 8 in the present case uses a flowing water tank for cooling, and after extrusion, the cable core 1 needs to pass through at least 1-2 meters of natural air cooling before being cooled in the flowing water cooling station 8, which is a known technology and is not shown in detail in the figure.

[0067] The above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements will not make the essence of the corresponding technical solutions deviate from the protection scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing a high-temperature resistant loose-tube optical cable for aviation, comprising a cable core (1), characterized in that, The outer side of the cable core (1) is provided with a buffer layer (2) and a sheath layer (3) in sequence. The buffer layer (2) is composed of a polytetrafluoroethylene tape (21) that is spirally glued to the outer end of the cable core (1). An expansion layer (22) is provided at the end of the polytetrafluoroethylene tape (21) facing the cable core (1). The expansion layer (22) can be heated and tightly attached between the buffer layer (2) and the cable core (1). The method includes the following steps: Step 1: The cable core (1) is guided and pulled on the frame (4) along the processing sequence direction by the traction equipment, and passes through the winding station (5), extrusion station (6), extrusion station (7) and cooling station (8) set on the frame (4) in sequence. Step 2: When the cable core (1) passes through the winding station (5), the winding machine (41) on the winding station (5) winds up the polytetrafluoroethylene tape (21) and attaches it to the outer end of the cable core (1). Step 3: The edge of the polytetrafluoroethylene tape (21) bonded to the outer end of the cable core (1) is extruded through the extrusion station (6); Step 4: A sheath layer (3) is formed on the outer end of the buffer layer (2) through the extrusion station (7), and the sheath layer (3) is cooled through the cooling station (8); The winding machine (41) includes: A wrapping disc (411) is rotatably mounted on a frame (4) and coaxially located at the outer end of the cable core (1); The wrapping reel (411) is provided with a winding reel (412), and the winding reel (412) is provided with a polytetrafluoroethylene strip (21) wound into a roll. As the wrapping reel (411) rotates, it moves circumferentially at the outer end of the cable core (1), so that the polytetrafluoroethylene strip (21) is spirally wrapped around the outer end of the cable core (1). There are two winding reels (412), each winding reel (412) is inclined to the cable core (1), and the distances between the two winding reels (412) and the wrapping reel (411) are not equal; The polytetrafluoroethylene tape (21) has a groove (211) in the middle. Both sides of the groove (211) are adhesive surfaces. A flat airbag (212) is embedded in the groove (211). The flat airbag (212) is glued in the groove (211) and is on the same plane as the adhesive surface of the polytetrafluoroethylene tape (21).

2. The method for preparing a high-temperature resistant loose-tube optical cable for aviation according to claim 1, characterized in that, The flat airbag (212) is filled with carbon dioxide gas.

3. The method for preparing a high-temperature resistant loose-tube optical cable for aviation according to claim 2, characterized in that, The PTFE strips (21) on the two winding reels (412) have the same helical pitch, and the PTFE strip (21) on the winding reel (412) away from the wrapping reel (411) winds around the middle of the helical pitch formed by the PTFE strip (21) on the other winding reel (412). The helical pitch formed by the polytetrafluoroethylene tape (21) is smaller than the width of the polytetrafluoroethylene tape (21).

4. The method for preparing a high-temperature resistant loose-tube optical cable for aviation according to claim 3, characterized in that, The extrusion station (6) includes: A hot pressing block (61) is provided, which is arranged in a circle around the outer end of the cable core (1). The hot pressing block (61) is in the shape of an arc block. A convex ring (611) is provided on both sides along the axial direction of the cable core (1). The convex ring (611) protrudes towards the side of the cable core (1) and intersects with the moving path of the spiral outer end of the polytetrafluoroethylene tape (21) protruding from the outer end of the cable core (1). An electric heating plate (612) is provided between the two convex rings (611). The distance between the electric heating plate (612) and the outer end of the cable core (1) is less than the distance between the convex ring (611) and the cable core (1), and does not intersect with the moving path of the spiral outer end of the polytetrafluoroethylene tape (21) protruding from the outer end of the cable core (1).

5. The method for preparing a high-temperature resistant loose-tube optical cable for aviation according to claim 4, characterized in that, Each of the heat-pressing blocks (61) can slide elastically along the radial direction of the cable core (1).

6. The method for preparing a high-temperature resistant loose-tube optical cable for aviation according to claim 5, characterized in that, The sides of the adjacent convex rings (611) are in contact with each other, and the convex rings (611) are made of heat-resistant rubber.

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