High-flame-retardant self-supporting copper sheath fire-resistant cable for intrinsic safety instrument

Abstract

The utility model discloses a high flame retardation self-supporting copper sheath intrinsic safety instrument fireproof cable, comprising an external sheath layer, the inner side of the external sheath layer is provided with a copper sheath layer and a self-supporting member, the inner side of the copper sheath layer is provided with a fireproof layer, a first flame retardation polyester belt is arranged between the fireproof layer and a cable core, and a second flame retardation polyester belt is arranged between the cable core and the self-supporting member. A first unit is arranged on the inner side of the cable core, a second flame-retardant polyester belt is arranged on the inner side of the first unit, a wire core is arranged on the inner side of the second flame-retardant polyester belt, an insulating layer is arranged on the inner side of the wire core, a conductor is arranged on the inner side of the insulating layer, a second unit is arranged on one side of the first unit, and a third unit is arranged on one side of the second unit. One side of the third unit is provided with the fourth unit, and the external sheath layer is made by extruding a high-flame-retardant and weather-resistant high polymer material and is of an 8-shaped and calabash-shaped structure. The self-supporting piece is arranged, so that the overall tensile capacity of the cable is improved; the copper sheath layer is a cavity cylinder, and the surface of the copper sheath layer is of a corrugated structure.

Description

Technical Field

[0001] The utility model relates to the technical field of cables, in particular to a highly flame-retardant self-supporting copper sheathed fire-resistant cable for intrinsically safe instruments. Background Art

[0002] Instrument cable is a type of cable used in industrial automation fields such as measurement, control, and signal transmission. It is commonly used in electronic computer systems, monitoring circuits, and automation control systems for signal transmission and detection instrument and meter connections.

[0003] At present, the common instrument cables on the market mainly use conductors, insulation layers, shielding layers, outer sheath layers, etc. as cable components, where the conductor and insulation layer form the core, and two or more cores are twisted to form a unit. Instrument cables with this structure usually have the following problems:

[0004] 1. Susceptible to mechanical damage. The wire core is relatively thin and the outer diameter of the cable itself is small, which makes it easy to be damaged by external forces, such as pulling, abrasion, or even breaking;

[0005] 2. Susceptible to interference. The signal of the instrument cable may be subject to external electromagnetic interference, which may cause unstable signal transmission and even data loss;

[0006] 3. Susceptible to the influence of humidity and temperature. The performance of the cable is affected by humidity and temperature. When the cable is in a humid environment or the temperature is too high, the insulation performance of the cable may be reduced, the signal transmission may be unstable, and even the cable may be burned;

[0007] 4. Short service life. The outer sheath is made of ordinary polyvinyl chloride, polyolefin and other materials. Such materials are not weather-resistant. In an environment exposed to wind and sun, they are very likely to crack due to wind aging, sun aging and heat aging, shortening the service life. In addition, in the event of a fire, the outer sheath material cannot be fireproof and will further burn into the cable.

[0008] 5. It is susceptible to being eaten by rats and ants. Due to some factors, rats and ants may visit computer rooms or other environments. After eating the outer sheath, they will continue to eat the units inside the cable, which will directly affect the unstable or interrupted signal transmission, and the cable will not be able to operate normally. Utility Model Content

[0009] In view of the deficiencies in the prior art, the utility model provides a highly flame-retardant self-supporting copper sheathed intrinsically safe fire-resistant cable for instruments, which solves the problems of the existing common instrument cables on the market, whose structure mainly uses conductors, insulation layers, shielding layers, external sheath layers, etc. as cable components, and are susceptible to mechanical damage, interference, humidity and temperature, short lifespan, and are susceptible to being gnawed by rats and ants, which further affects the normal operation of the cable.

[0010] To achieve the above objectives, the utility model is implemented through the following technical solutions: a highly flame-retardant self-supporting copper sheathed fire-resistant cable for intrinsically safe instruments, comprising an outer sheath layer, a copper sheath layer and a self-supporting member are arranged on the inner side of the outer sheath layer, a fire-resistant layer is arranged on the inner side of the copper sheath layer, a first flame-retardant polyester tape is arranged between the fire-resistant layer and the cable core, a first unit is arranged on the inner side of the cable core, a second flame-retardant polyester tape is arranged on the inner side of the first unit, a wire core is arranged on the inner side of the second flame-retardant polyester tape, an insulating layer is arranged on the inner side of the wire core, a conductor is arranged on the inner side of the insulating layer, a second unit is arranged on one side of the first unit, a third unit is arranged on one side of the second unit, and a fourth unit is arranged on one side of the third unit.

[0011] Preferably, the outer sheath layer is made of highly flame-retardant and weather-resistant polymer material and has an "8"-shaped, gourd-shaped structure.

[0012] Preferably, the copper sheath layer is a hollow cylinder with a corrugated surface structure.

[0013] Preferably, the self-supporting member is galvanized steel stranded wire.

[0014] Preferably, the refractory layer is a coated mica tape.

[0015] Preferably, the unit is composed of two wire cores and a second flame-retardant polyester tape.

[0016] Preferably, the wire core consists of an insulating layer and a conductor.

[0017] Beneficial Effects

[0018] The utility model provides a highly flame-retardant self-supporting copper sheathed fire-resistant cable for intrinsically safe instruments, which has the following beneficial effects:

[0019] (1) An outer sheath layer is provided, which is made of highly flame-retardant and weather-resistant polymer materials, so that the cable has good flame-retardant and weather-resistant properties, thereby improving the service life of the cable;

[0020] (2) A self-supporting member is provided, which is made of galvanized steel stranded wire to prevent the cable as a whole or in units from being broken during the laying process, thereby improving the overall tensile strength of the cable;

[0021] (3) A copper sheath layer is provided, which is a hollow cylindrical structure with a corrugated surface, which can enhance the impact resistance and wear resistance of the cable;

[0022] (4) A copper sheath layer is provided, which is a complete tubular shape with good air tightness, preventing moisture from entering the cable, thereby improving the moisture-proof and waterproof capabilities of the cable; the copper sheath layer can serve as a protective layer, and rats and ants will not be able to gnaw the copper sheath layer, and rats and ants will not be able to gnaw the units in the cable, so that the cable remains a complete overall structure;

[0023] (5) A copper sheath layer is provided, and copper is used as a shielding material. Copper is a non-magnetic material and will not be magnetized. It can be used as a shielding material. From the radial direction of the cable and the surface of the cable, the copper sheath layer completely covers the inside of the cable, and the shielding coverage rate reaches 100%, which can effectively improve the anti-interference ability of the cable;

[0024] (6) A copper sheath layer is provided. Copper has a melting point of 1083°C and a boiling point of 2567°C. When the cable is operating normally and a fire occurs in the air, the copper sheath layer will not burn after the outer sheath layer burns out, thus preventing the flame from further burning the inside of the cable.

[0025] (7) A fire-resistant layer is provided. The fire-resistant layer material adopts coated mica tape. Under high temperature flame, the fire-resistant layer can form a ceramic-like coating around the flame-retardant polyester tape, and has excellent high temperature resistance and combustion resistance;

[0026] (8) A flame-retardant polyester tape is provided, which has excellent high temperature resistance and flame retardant properties. When a fire occurs or encounters a fire source, the flame-retardant polyester tape can effectively prevent the spread of flames, so that the units and cores in the cable can avoid high temperature melting and protect the safety of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a structural schematic diagram of a highly flame-retardant self-supporting copper sheathed fire-resistant cable for intrinsically safe instruments described in the utility model;

[0028] Figure 2 It is a structural schematic diagram of the self-supporting member of the utility model;

[0029] Figure 3 It is a structural schematic diagram of the first unit of the utility model;

[0030] Figure 4 This is a schematic diagram of the wire core structure of the utility model;

[0031] Figure 5 This is the appearance diagram of the copper sheath layer of the utility model;

[0032] In the figure: 1-outer sheath layer, 2-self-supporting member, 21-galvanized steel wire, 3-copper sheath layer, 4-fire-resistant layer, 5-first flame-retardant polyester tape, 6-first unit, 61-second flame-retardant polyester tape, 7-core, 71-conductor, 72-insulating layer, 8-second unit, 9-third unit, 10-fourth unit, 11-cable core. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] Example:

[0035] See also Figure 1 As shown, the utility model provides a technical solution: a structure of a highly flame-retardant self-supporting copper sheathed intrinsically safe fire-resistant cable for instrumentation, comprising an outer sheath layer 1, a copper sheath layer 3 and a self-supporting member 2 are arranged on the inner side of the outer sheath layer 1, a fire-resistant layer 4 is arranged on the inner side of the copper sheath layer 3, a first flame-retardant polyester tape 5 is arranged between the fire-resistant layer 4 and the cable core 11, a first unit 6 is arranged on the inner side of the cable core 11, a second flame-retardant polyester tape 61 is arranged on the inner side of the first unit 6, a wire core 7 is arranged on the inner side of the second flame-retardant polyester tape 61, an insulating layer 72 is arranged on the inner side of the wire core 7, a conductor 71 is arranged on the inner side of the insulating layer 72, a second unit 8 is arranged on one side of the first unit 6, a third unit 9 is arranged on one side of the second unit 8, and a fourth unit 10 is arranged on one side of the third unit 9.

[0036] In order to improve the service life of the cable, in the present embodiment, as a preference, the outer sheath layer 1 is extruded by an extruder to form a layer of flame retardant and weather resistant sheath cable material, which is evenly surrounded by the copper sheath layer 3 and the self-supporting member 2. The cable material contains flame retardant and carbon black. The flame retardant can make the cable material flame retardant, and the carbon black can make the cable material weather resistant, so that the cable can be used for a long time in a complex environment, thereby improving the service life of the cable. As a preference, further, the outer sheath layer 1 is an "8"-shaped, gourd-shaped structure.

[0037] In order to improve the overall tensile strength of the cable, in the present embodiment, as a preference, a self-supporting member 2 is provided on the inner side of the outer sheath layer 1. The self-supporting member 2 is formed by twisting 7 galvanized steel wires 21. The galvanized steel wires 21 have high tensile strength and corrosion resistance, which prevents the cable as a whole or unit 6 from being broken during the laying process of the cable, thereby improving the overall tensile strength and wear resistance of the cable.

[0038] In order to improve the anti-interference ability of the cable, in the present embodiment, as a preference, a copper sheath layer 3 is arranged on the inner side of the outer sheath layer 1. Copper has excellent plasticity and ductility and is easy to process. Usually, a copper strip with a thickness of 0.5 mm is selected and welded into a complete cylindrical copper tube by argon arc welding equipment. The cylindrical copper tube is then corrugated by a corrugator to finally form the copper sheath layer 3. Copper is a non-magnetic material that will not be magnetized and can be used as a shielding material. From the radial direction of the cable and the surface of the cable, the copper sheath layer 3 completely covers the inside of the cable, and the shielding coverage rate reaches 100%, which can effectively improve the anti-interference ability of the cable. As a preference, further, the copper sheath layer 3 is a hollow cylindrical copper tube with a corrugated surface.

[0039] In order to improve the flame retardant ability of the cable, in this embodiment, preferably, a copper sheath layer 3 is arranged on the inner side of the outer sheath layer 1. Copper is a metal and an inorganic substance with a melting point of 1084°C and a boiling point of 2567°C. When the cable is operating normally and a fire occurs in the air, after the outer sheath layer 1 is burned out, the copper sheath layer 3 will not burn, thereby preventing the flame from further burning the inside of the cable.

[0040] In order to improve the impact resistance of the cable, in this embodiment, preferably, a copper sheath layer 3 is arranged on the inner side of the outer sheath layer 1. The copper sheath layer 3 is a hollow cylindrical copper tube with a corrugated surface. Copper has excellent plasticity and ductility and is easy to process. When the cable is impacted, the copper will deform but will not break or shatter. When the outer sheath layer 1 is subjected to external mechanical impact, the copper sheath layer 3 remains a complete overall structure.

[0041] In order to improve the moisture-proof, waterproof and rat-proof capabilities of the cable, in the present embodiment, preferably, a copper sheath layer 3 is arranged on the inner side of the outer sheath layer 1, and the copper sheath layer 3 is a copper tube with a hollow cylinder and a corrugated surface. In the radial direction of the cable, the copper sheath layer 3 is a complete tubular shape with good air tightness to prevent moisture from entering the interior of the cable; preferably, further, copper is a metal with a Vickers hardness of 343 to 369 MPa and a Brinell hardness of 235 to 878 MPa. After the outer sheath layer 1 of the cable is completely eaten by rats and ants, the copper sheath layer 3 can be used as a protective layer, and rats and ants will not be able to eat the copper sheath layer 3, so that the cable is still a complete overall structure.

[0042] In order to improve the fire resistance of the cable, in the present embodiment, as a preference, a fire-resistant layer 4 is arranged on the inner side of the copper sheath layer 3. The fire-resistant layer 4 is formed by a coated mica tape wrapped around the first flame-retardant polyester tape 5 by a wrapping machine. The coated mica tape is made of mica ore resistant to high temperatures above 950°C and processed into mica paper with a scaly structure. Under high-temperature flames, the fire-resistant layer 4 can form a ceramic-like coating around the first flame-retardant polyester tape 5, which can improve the high temperature resistance and combustion resistance of the cable.

[0043] In order to improve the overall flame retardant ability of the cable, in the present embodiment, preferably, a first flame retardant polyester tape 5 is provided on the inner side of the fire-resistant layer 4, and the first flame retardant polyester tape 5 is wrapped around the cable core 11 by a wrapping machine. In the event of a fire or encountering a fire source, the first flame retardant polyester tape 5 can effectively prevent the spread of flames, thereby preventing the first unit 6 in the cable from melting at high temperature and protecting the safety of the cable.

[0044] In order to improve the overall flame retardant ability of the cable, in the present embodiment, preferably, a second flame retardant polyester tape 61 is arranged on the outside of the core 7, the thickness of the second flame retardant polyester tape 61 is less than the thickness of the first flame retardant polyester tape 5, and the second flame retardant polyester tape 61 is wrapped around the core 7 by a wrapping machine. In the event of a fire or a fire source, the second flame retardant polyester tape 61 can effectively prevent the spread of flames, thereby preventing the core 7 in the cable from melting due to high temperature and protecting the safety of the cable.

[0045] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions. The sentence "includes an element defined by ... does not exclude the existence of other identical elements in the process, method, article or device including the element".

[0046] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A highly flame-retardant self-supporting copper sheathed intrinsically safe instrument fire-resistant cable, comprising an outer sheath layer (1), characterized in that: A copper sheath layer (3) and a self-supporting member (2) are arranged on the inner side of the outer sheath layer (1); a fire-resistant layer (4) is arranged on the inner side of the copper sheath layer (3); a first flame-retardant polyester tape (5) is arranged between the fire-resistant layer (4) and the cable core (11); a first unit (6) is arranged on the inner side of the cable core (11); a second flame-retardant polyester tape (61) is arranged on the inner side of the first unit (6); a wire core (7) is arranged on the inner side of the second flame-retardant polyester tape (61); an insulating layer (72) is arranged on the inner side of the wire core (7); a conductor (71) is arranged on the inner side of the insulating layer (72); a second unit (8) is arranged on one side of the first unit (6); a third unit (9) is arranged on one side of the second unit (8); and a fourth unit (10) is arranged on one side of the third unit (9).

2. A highly flame-retardant self-supporting copper sheathed intrinsically safe fire-resistant cable for instrumentation according to claim 1, characterized in that: The outer sheath layer (1) is an "8"-shaped, gourd-shaped structure.

3. A highly flame-retardant self-supporting copper sheathed intrinsically safe fire-resistant cable for instrumentation according to claim 1, characterized in that: The copper sheath layer (3) is a hollow cylinder with a corrugated surface structure.

4. A highly flame-retardant self-supporting copper sheathed intrinsically safe instrument fire-resistant cable according to claim 1, characterized in that: The self-supporting member (2) is a galvanized steel stranded wire, which improves the overall tensile strength of the cable.

5. A highly flame-retardant self-supporting copper sheathed intrinsically safe instrument fire-resistant cable according to claim 1, characterized in that: The fire-resistant layer (4) is a coated mica tape.

6. A highly flame-retardant self-supporting copper sheathed intrinsically safe fire-resistant cable for instrumentation according to claim 1, characterized in that: The thickness of the second flame-retardant polyester tape (61) is smaller than the thickness of the first flame-retardant polyester tape (5).

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