Intrinsic safety flexible high flame retardant instrument cable

Abstract

The utility model discloses a kind of intrinsic safety flexible high flame-retardant instrument cable, belong to wire and cable technical field, including cable core, from inside to outside are successively wrapped in the outer tape of cable core, inner sheath, braided shielding layer and outer sheath, cable core is composed of multiple wire core and two reinforcing pieces, two reinforcing pieces are symmetrically arranged in the intermediate position of cable core, multiple wire core is distributed in the outside of reinforcing piece, reinforcing piece is twisted by multiple nylon filaments and is wrapped with polyvinyl chloride material in outside, wire core is by multiple conductor and extruded in the outside of conductor Insulating layer constitutes insulated wire core, the utility model is not prone to insulated wire core short core, cause power failure accident, while the wear resistance of inner and outer sheath is strong, after long time moving, sheath cracking abrasion phenomenon also does not appear, ensure that the cable can be safely used in mobile laying place of intrinsically safe electrical system.

Description

Technical Field

[0001] This utility model belongs to the field of wire and cable technology, and more specifically, relates to an intrinsically safe flexible high flame-retardant instrument cable. Background Technology

[0002] Intrinsically safe instrument cables are mainly used for transmitting weak electrical signals in intrinsically safe electrical systems. By increasing the insulation thickness and using special cable structure design, the cables have characteristics such as low capacitance, low inductance, flame retardancy, and anti-interference. They are mainly used in fixed installation locations, and the technology is relatively mature at present. However, the technology for intrinsically safe instrument cables used in mobile installation locations (such as those installed together with tank tracks) is still a bottleneck.

[0003] Traditional intrinsically safe instrument cables have the following defects when used in mobile installation sites for a long time: the insulation core is prone to shorting, causing power outage accidents; at the same time, the sheath layer has poor wear resistance, and the sheath is prone to cracking and wear after long-term movement. Utility Model Content

[0004] The main objective of this invention is to provide an intrinsically safe flexible high flame-retardant instrument cable to solve the problems mentioned above in the background.

[0005] According to a first aspect of this utility model, an intrinsically safe flexible high flame-retardant instrument cable is provided, comprising a cable core, a wrapping tape, an inner sheath, a braided shielding layer, and an outer sheath wrapped around the cable core from the inside out. The cable core is composed of multiple wire cores and two reinforcing members, which are symmetrically arranged in the middle position of the cable core. The multiple wire cores are distributed around the outside of the reinforcing members. The reinforcing members are made of multiple strands of nylon filaments twisted together and wrapped with polyvinyl chloride material on the outside. The wire cores are composed of multiple conductors and an insulation layer extruded on the outside of the conductors to form an insulated wire core.

[0006] In a specific embodiment of this utility model, the inner sheath is extruded onto the outside of the bag strap.

[0007] In a specific embodiment of this utility model, the outer sheath is extruded and formed on the outside of the braided shielding layer.

[0008] In a specific embodiment of this invention, an anti-slip agent is provided on the outer side of the insulating layer.

[0009] In a specific embodiment of this utility model, the inner sheath is made of flame-retardant and soft polyvinyl chloride material.

[0010] In a specific embodiment of this utility model, the outer sheath is made of flame-retardant and flexible polyvinyl chloride material.

[0011] In a specific embodiment of this utility model, the flame-retardant flexible polyvinyl chloride material has a tensile strength of 17 MPa, a hardness of 85A, and an oxygen index of 32A.

[0012] In a specific embodiment of this invention, the tensile strength of the nylon filament is not less than 72 kgf.

[0013] One of the above-described technical solutions of this utility model has at least one of the following advantages or beneficial effects:

[0014] This utility model employs a reinforcing member in the middle, which is made of multiple nylon filaments twisted together. The twisted nylon filaments are then extruded with a layer of polyvinyl chloride material, ensuring the roundness of the cable and its good tensile strength. This cable is less prone to short cores in the insulation, which could lead to power outages. At the same time, the inner and outer sheaths have strong wear resistance and will not crack or wear even after long-term movement, ensuring that the cable can be safely used in mobile installation locations of intrinsically safe electrical systems. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0016] Figure 1 This is a schematic diagram of the structure of an intrinsically safe flexible high flame-retardant instrument cable in one embodiment of the present invention;

[0017] Figure 2 This is a schematic diagram of the core structure in one embodiment of the present invention. Detailed Implementation

[0018] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0019] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0020] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly indicating the number of indicated technical features, or implicitly indicating the sequential relationship of the indicated technical features.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more features.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, it can be a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection or a connection that can communicate with each other; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two elements, an indirect connection, or an interaction between two elements.

[0023] The following disclosure provides many different implementation methods or examples for different solutions to implement this utility model.

[0024] Reference Figures 1 to 2 As shown, an intrinsically safe flexible high flame-retardant instrument cable is provided, including a cable core, and from the inside out, a wrapping tape 1, an inner sheath 2, a braided shielding layer 3, and an outer sheath 4 are wrapped around the cable core. The cable core is composed of multiple wire cores 5 and two reinforcing members 6. The two reinforcing members 6 are symmetrically arranged in the middle position of the cable core. Multiple wire cores 5 are distributed around the outside of the reinforcing members 6. The reinforcing members 6 are made of multiple nylon filaments twisted together and wrapped with polyvinyl chloride material on the outside. The wire cores 5 are composed of multiple conductors 51 and an insulation layer 52 extruded on the outside of the conductors 51 to form an insulated wire core.

[0025] In this embodiment, to prevent the cable from shorting during long-term mobile installation, a reinforcing member 6 is added in the middle of the cable core. This reinforcing member 6 is made of multiple nylon filaments twisted together. The twisted nylon filaments are then wrapped with a layer of polyvinyl chloride material, which ensures the roundness of the cable and also ensures that the cable has good tensile strength. Through the multi-layer sheath, the cable is protected from wear during mobile installation, ensuring that the cable can be safely used in mobile installation locations of intrinsically safe electrical systems.

[0026] In one embodiment of this utility model, the inner sheath 2 is extruded on the outside of the wrapping tape 1, and the outer sheath 4 is extruded on the outside of the braided shielding layer 3. The inner sheath 2 and the outer sheath 4 are extruded by extrusion. This method can make the cable core structure more compact and avoid the phenomenon of misalignment and breakage caused by displacement of the insulated core after repeated bending.

[0027] In one embodiment of this utility model, the pitch ratio of the insulated wire cores is controlled within 14 times when they are stranded. An anti-slip agent is provided on the outer side of the insulation layer 52. The main component of the anti-slip agent is silicone oil, which ensures that the single wire moves a short distance and generates little frictional resistance when the cable is bent. This prevents the insulated wire cores from loosening, bending, or breaking under repeated bending, making the cable easier to bend. After implementing the above measures, the finished cable can bend more than 100,000 times.

[0028] In one embodiment of this utility model, to prevent wear of the sheath layer when the cable is repeatedly bent, the inner sheath 2 is made of flame-retardant soft polyvinyl chloride (PVC) material, and the outer sheath 4 is also made of flame-retardant soft PVC material. Preferably, through a special formula design, the flame-retardant soft PVC material has a tensile strength of 17 MPa, a hardness of 85A, and an oxygen index of 32A, which is superior to traditional PVC materials. This ensures that the outer sheath does not wear after repeated cable movement, while also ensuring that the cable has good flame-retardant performance and flexibility. The flame-retardant rating of the finished cable reaches Class A.

[0029] In one embodiment of this utility model, the tensile strength of the nylon filament is not less than 72 kgf. During product design, the number of nylon filaments is appropriately adjusted according to the size of the cable cross-section to ensure that the core does not break when the cable is repeatedly bent.

[0030] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An intrinsically safe, flexible, highly flame-retardant instrument cable, characterized in that, The cable core includes a cable tape (1), an inner sheath (2), a braided shielding layer (3), and an outer sheath (4) wrapped around the cable core from the inside out. The cable core is composed of multiple wire cores (5) and two reinforcing members (6). The two reinforcing members (6) are symmetrically arranged in the middle position of the cable core. The multiple wire cores (5) are distributed around the outside of the reinforcing members (6). The reinforcing members (6) are made of multiple nylon filaments twisted together and wrapped with polyvinyl chloride material on the outside. The wire cores (5) are composed of multiple conductors (51) and an insulation layer (52) extruded on the outside of the conductors (51) to form an insulated wire core.

2. The intrinsically safe flexible high flame-retardant instrument cable according to claim 1, characterized in that, The inner sheath (2) is extruded onto the outside of the strap (1).

3. The intrinsically safe flexible high flame-retardant instrument cable according to claim 1, characterized in that, The outer sheath (4) is extruded onto the outside of the braided shielding layer (3).

4. The intrinsically safe flexible high flame-retardant instrument cable according to claim 1, characterized in that, The outer side of the insulating layer (52) is provided with an anti-slip agent.

5. The intrinsically safe flexible high flame-retardant instrument cable according to claim 1, characterized in that, The inner sheath (2) is made of flame-retardant and soft polyvinyl chloride material.

6. The intrinsically safe flexible high flame-retardant instrument cable according to claim 1, characterized in that, The outer sheath (4) is made of flame-retardant and soft polyvinyl chloride material.

7. The intrinsically safe flexible high flame-retardant instrument cable according to claim 5 or 6, characterized in that, The flame-retardant flexible polyvinyl chloride material has a tensile strength of 17 MPa, a hardness of 85 A, and an oxygen index of 32 A.

8. The intrinsically safe flexible high flame-retardant instrument cable according to claim 1, characterized in that, The tensile strength of the nylon filament is not less than 72 kgf.

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