Longitudinal watertight cable for underwater exploration robot and preparation process of longitudinal watertight cable

Abstract

The invention discloses a longitudinal watertight cable for an underwater exploration robot and a preparation process of the longitudinal watertight cable. The cable comprises a cable core formed by a plurality of wire cores, a shielding layer arranged outside the cable core, a water-blocking tape arranged outside the shielding layer, an inner protective layer arranged outside the water-blocking tape, an armor layer arranged outside the inner protective layer, a first outer protective layer arranged outside the armor layer, a tensile layer arranged outside the first outer protective layer and a second outer protective layer arranged outside the tensile layer, single-component water-blocking glue is arranged in gaps among the wire cores; according to the method, each conductor is extruded and coated with an insulating layer in an extrusion mode, every two conductors are twisted to form a wire core, after the wire cores are twisted into a cable core, the cable core is wrapped with a shielding layer and filled with single-component water-blocking glue, and then a water-blocking tape, an inner protection layer, an armor layer, a first outer protection layer, a tensile layer and a second outer protection layer are sequentially processed and coated.

Description

Technical Field

[0001] The invention relates to the field of cables, in particular to a longitudinal watertight cable for an underwater detection robot and a preparation process thereof. Background Art

[0002] The existing watertight cable for underwater detection robots includes a conductor twisted and sealed with water-blocking glue, and a sheath of chloroprene rubber or TPU. The problems are that the conductor is tightly bonded to the insulation layer after the water-blocking glue is added, and it is difficult to strip the wire during end processing. The chloroprene rubber sheath is not wear-resistant and can be easily scratched by sharp objects such as rocks during dragging. The TPU outer sheath has a high water absorption rate. After being immersed in water for a long time, moisture will slowly penetrate into the cable, affecting the insulation resistance of the cable. Summary of the invention

[0003] The present invention provides a longitudinal watertight cable for an underwater detection robot and a preparation process thereof, so as to solve the problems of the prior art watertight cable for underwater detection robots that are difficult to strip off the insulation, the sheath is not wear-resistant, and the insulation resistance decreases after long-term immersion in water.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: A longitudinal watertight cable for an underwater detection robot, comprising a cable core, a shielding layer (4), a water-blocking tape (5), an inner sheath (6), an armor layer (7), a first outer sheath (8), a tensile layer (9), and a second outer sheath (10); The cable core comprises a plurality of strands twisted into a cable core, each strand of the core comprises two groups of twisted conductors (1), each conductor (1) is coated with an insulating layer (2), and the two groups of conductors (1) in each strand of the core are twisted and encapsulated with a two-component water-blocking adhesive as a filler; The shielding layer (4) is wrapped around the entire cable core, and the gaps between the wire cores in the shielding layer are filled with a single-component water-blocking glue (3); The water-blocking tape (5) is a double-layer thin non-woven fabric, the middle of the interlayer of the double-layer thin non-woven fabric is coated with sodium polyacrylate, and the water-blocking tape (5) is wrapped around the outside of the shielding layer (4); The material of the inner protective layer (6) is foamed polyurethane, and the inner protective layer (6) is coated on the outside of the water blocking tape (5); The armor layer (7) is woven outside the inner protective layer (6); The material of the first outer protective layer (8) is foamed polyurethane, and the first outer protective layer (8) is coated on the outside of the armor layer (7); The material of the tensile layer (9) is liquid crystal polymer LCP fiber, and the tensile layer (9) is woven outside the first outer protective layer (8); The material of the second outer protective layer (10) is radiation cross-linked chlorosulfonated polyethylene, and the second outer protective layer (10) is coated outside the tensile layer (9).

[0005] Furthermore, the material of each conductor (1) is based on oxygen-free copper as a base, and a silver layer is plated outside the base.

[0006] Furthermore, the material of the insulating layer (2) is high-density polyethylene.

[0007] Furthermore, the one-component water-blocking adhesive (3) is formed by mixing EVA resin, tackifying resin, wax and antioxidant.

[0008] Furthermore, the foamed polyurethane used as the material of the inner protective layer (6) and the first outer protective layer (8) is obtained by adding a nitrogen-based foaming agent to polyether polyurethane.

[0009] Furthermore, the material of the armor layer (7) is tinned copper wire.

[0010] Furthermore, the tensile layer (9) is sandwiched between the first outer protective layer (8) and the second outer protective layer (10), and the bonding surfaces of the tensile layer (9) and the first outer protective layer (8) and the second outer protective layer (10) are respectively coated with a single-component water-blocking adhesive.

[0011] Furthermore, the radiation cross-linked chlorosulfonated polyethylene used as the material of the second outer protective layer (10) is obtained by taking polyethylene as a matrix and introducing chlorine and chlorosulfonyl groups into the polyethylene molecular chain.

[0012] A process for preparing the longitudinal watertight cable for the underwater detection robot comprises the following steps: Step 1: Extruding an insulating layer (2) onto each conductor (1) by a high-temperature hot-melt high-pressure extrusion method; Step 2: Using a polycrystalline Hough mold to twist the conductors (1) in pairs to form a wire core, and when twisting the wire core, a two-component water-blocking adhesive is cast as a filler, and the two-component water-blocking adhesive is dried and cured in an infrared sintering furnace. When twisting, the twisting direction is left-handed, and a 30% back-twist rate constant tension is used for wire pay-off; Step 3: Use a nylon Huff mold to twist the strands of wire cores into a cable core. The overall twisting direction is left-handed, and a non-back-twisting active constant tension pay-off is used during twisting. Step 4, wrapping the shielding layer (4) around the cable core, and filling the gaps between the wire cores in the shielding layer (4) with a single-component water-blocking glue (3); Step 5: Wrap the water-blocking tape (5) around the shielding layer (4) in a reverse wrapping manner; Step 6, extruding and coating the inner protective layer (6) outside the water blocking tape (5); Step 7, cross-weaving the armor layer (7) outside the inner protective layer (6), applying hot melt adhesive to the gaps and surface of the armor layer (7) during weaving, and performing a rapid curing process on the hot melt adhesive; Step 8: The first outer sheath (8) and the second outer sheath (10) are covered on the outer side of the armor layer (7) by a double-layer co-extrusion method; a braiding machine and a glue coating machine are connected in series between the front and rear heads of the double-layer co-extrusion equipment; the tensile layer (9) is braided between the first outer sheath (8) and the second outer sheath (10) by the braiding machine; and the bonding surfaces of the tensile layer (9) and the first outer sheath (8) and the second outer sheath (10) are coated with a single-component water-blocking glue by the glue coating machine.

[0013] The principle of the present invention is to fill the conductor with a two-component expandable water-blocking adhesive, which expands rapidly after encountering water and fills the conductor gap to achieve the purpose of water blocking without adhering to the insulation. By adopting a specially formulated irradiated chlorosulfonated polyethylene sheath, the problems of the sheath's poor wear resistance and high water absorption are solved.

[0014] Compared with the prior art, the present invention has the following advantages: Two-component swelling water-blocking adhesive, non-sticky, easy to peel off insulation, good processability. The sheath material is lower in cost than TPU and easier to process than chloroprene rubber. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of an embodiment of the present invention. DETAILED DESCRIPTION

[0016] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0017] like Figure 1 As shown, this embodiment discloses a longitudinal watertight cable for underwater detection robots, including a cable core, a shielding layer 4, a water-blocking tape 5, an inner sheath 6, an armor layer 7, a first outer sheath 8, a tensile layer 9, and a second outer sheath 10. The cable core is formed by twisting multiple cores, the shielding layer 4 is wrapped around the entire cable core, and the gaps between the cores in the shielding layer are evenly filled with a single-component water-blocking glue 3. The water-blocking tape 5 is wrapped around the shielding layer 4, the inner sheath 6 is coated on the water-blocking tape 5, and the armor layer 7 is woven on the inner sheath 6. The first outer sheath 8, the tensile layer 9, and the second outer sheath 10 constitute an outer sheath structure, and the outer sheath structure is coated on the armor layer 7 as a whole. In the specific outer sheath structure, the first outer sheath 8 is coated on the armor layer 7, the tensile layer 9 is coated on the first outer sheath 8, and the second outer sheath 10 is coated on the tensile layer 9.

[0018] In this embodiment, each core of the cable core includes two groups of twisted conductors 1, each conductor 1 is made of oxygen-free copper as a matrix, and a silver layer is plated on the outside of the matrix, and each conductor 1 is coated with an insulation layer 2 with a thickness of 2um by high-temperature hot-melt extrusion, and the material of the insulation layer 2 is 0.97 density high-density polyethylene. When the two groups of conductors 1 in each core are twisted, a two-component water-blocking glue is encapsulated as a filler, and the glue A in the two-component water-blocking glue is a mixture of 31% EPDM rubber solution, 44% synthetic oil, 13% styrene-ethylene propylene rubber block copolymer solution, 1010 antioxidant 1%, 2% silicone rubber powder, and 9% acrylic resin powder by weight percentage, and the glue B is a mixture of 99% glycerol, 0.5% diethylene glycol, and 0.5% potassium persulfate by weight percentage, and the weight ratio of the AB glue is 4:1.

[0019] In this embodiment, the material of the shielding layer 4 is wrapped with an aluminum-plastic composite tape, and the shielding layer 4 is wrapped around the entire cable core. The single-component water-blocking adhesive 3 uniformly filled in the shielding layer 4 is a mixture of EVA resin, C5 / C9 petroleum resin, rosin pentaerythritol ester, polyethylene wax, calcium carbonate, antioxidant 1010, dioctyl phthalate, and styrene-butadiene-styrene, and the weight proportions of EVA resin, C5 / C9 petroleum resin, rosin pentaerythritol ester, polyethylene wax, calcium carbonate, antioxidant 1010, dioctyl phthalate, and styrene-butadiene-styrene are: 33%, 15%, 6%, 3%, 40%, 0.3%, 0.7%, and 2%.

[0020] In this embodiment, the water-blocking tape 5 is a double-layer thin non-woven fabric, the middle layer of the double-layer thin non-woven fabric is coated with sodium polyacrylate and then calendered and cured to form a tape, and the water-blocking tape 5 is reversely wrapped around the shielding layer 4.

[0021] In this embodiment, the material of the inner protective layer 6 is foamed polyurethane, and the inner protective layer 6 is coated on the outside of the water blocking tape 5 by extrusion. The foamed polyurethane is obtained by adding a nitrogen-based foaming agent to polyether polyurethane, wherein the weight ratio of the polyether polyurethane to the nitrogen-based foaming agent is 5%. The foamed polyurethane is heated and decomposed to generate gas, which expands the material to form a pore structure, so that the density of the polyether polyurethane is reduced from 1.18 to 0.73.

[0022] In this embodiment, the armor layer 7 is made of tinned copper wire, and the armor layer 7 is cross-woven outside the inner protective layer 6 .

[0023] In this embodiment, the material of the first outer sheath 8 is the same foamed polyurethane as the inner sheath 6, and the material of the second outer sheath 10 is radiation cross-linked chlorosulfonated polyethylene. The radiation cross-linked chlorosulfonated polyethylene used as the material of the second outer sheath 10 is obtained by introducing chlorine and chlorosulfonyl groups into the polyethylene molecular chain with polyethylene as the matrix. By adjusting the introduction ratio, the radiation cross-linked chlorosulfonated polyethylene has both the easy bonding property of rubber and the low water absorption and hydrolysis resistance of polyethylene.

[0024] In this embodiment, the material of the tensile layer 9 is liquid crystal polymer LCP fiber. The liquid crystal polymer LCP fiber hardly absorbs moisture and has a tensile strength more than ten times that of ordinary tensile fibers.

[0025] In this embodiment, the first outer sheath 8 and the second outer sheath 10 are coated on the outside of the armor layer 7 from the inside to the outside in sequence by a double-layer co-extrusion production method, and the first outer sheath 8 and the second outer sheath 10 are co-extruded by a weaving machine to weave the tensile layer 9 between the first outer sheath 8 and the second outer sheath 10, and a single-component water-blocking glue is coated on both sides of the braided tensile layer 9 by a glue coating machine, which can effectively improve the bonding force with the first outer sheath 8 and the second outer sheath 10. The outer sheath structure is composed of the first outer sheath 8, the braided tensile layer 9, and the second outer sheath 10, wherein the first outer sheath 8 is coated on the outside of the armor layer 7, the braided tensile layer 9 is coated on the outside of the first outer sheath 8, and the second outer sheath 10 is coated on the outside of the braided tensile layer 9, and the bonding surfaces of the braided tensile layer 9 and the first outer sheath 8 and the second outer sheath 10 are respectively bonded by single-component water-blocking glue. The one-component water-blocking adhesive is mixed with EVA resin, C5 / C9 petroleum resin, rosin pentaerythritol ester, polyethylene wax, calcium carbonate, antioxidant 1010, dioctyl phthalate, and styrene-butadiene-styrene. The weight proportions of EVA resin, C5 / C9 petroleum resin, rosin pentaerythritol ester, polyethylene wax, calcium carbonate, antioxidant 1010, dioctyl phthalate, and styrene-butadiene-styrene are 33%, 15%, 6%, 3%, 40%, 0.3%, 0.7%, and 2%.

[0026] This embodiment discloses a process for preparing the longitudinal watertight cable for the underwater detection robot, comprising the following steps: Step 1: Extrude and coat the insulating layer 2 onto each conductor 1 by high-temperature hot-melt high-pressure extrusion, and control the concentricity of the insulating layer 2 and the conductor 1 to be above 95%. The high-temperature hot-melt hot-pressing process parameters are 400°C.

[0027] Step 2: Use a polycrystalline Hough mold to twist the conductors 1 in pairs to form a core. When twisting the core, fill it with a two-component water-blocking adhesive as a filler. Use an infrared sintering furnace to dry and cure the two-component water-blocking adhesive. When twisting, the twisting direction is left-handed, and a 30% back-twist rate constant tension is used for pay-off.

[0028] Step 3: Use a nylon Huff mold to twist the strands of wire cores into a cable core. The overall twisting direction is left-handed, and a non-back-twisting active constant tension pay-off is used during twisting.

[0029] Step 4: Wrap the shielding layer 4 around the cable core, and fill the gaps between the wire cores in the shielding layer 4 with a single-component water-blocking glue 3.

[0030] Step 5: Wrap the water-blocking tape 5 around the shielding layer 4 in a reverse wrapping manner.

[0031] Step 6: Extruding and coating the inner protective layer 6 outside the water blocking tape 5.

[0032] Step 7, cross-weave the armor layer 7 outside the inner protective layer 6, apply hot melt adhesive to the gaps and surface of the armor layer 7 when weaving, and quickly cure the hot melt adhesive. The process parameters of the rapid curing treatment are: ambient temperature below 20°C, and curing wind speed of 3.2m-3.4m / s.

[0033] Step 8, using a double-layer co-extrusion method to cover the armor layer 7 with a first outer sheath 8 and a second outer sheath 10, connecting a braiding machine and a glue coating machine in series on the front and rear heads of the double-layer co-extrusion equipment, weaving a tensile layer 9 between the first outer sheath 8 and the second outer sheath 10 by the braiding machine, and coating the bonding surfaces of the tensile layer 9 and the first outer sheath 8 and the second outer sheath 10 with a single-component water-blocking glue by the glue coating machine.

[0034] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. The embodiments described in the present invention are merely descriptions of the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention. The various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction, and such combinations should also be regarded as the contents disclosed in the present disclosure as long as they do not violate the concept of the present invention. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0035] The present invention is not limited to the specific details of the above-mentioned embodiments. Within the technical concept of the present invention and without departing from the design concept of the present invention, various modifications and improvements made to the technical solution of the present invention by technical personnel in this field should fall within the protection scope of the present invention. The technical contents for which protection is sought in the present invention have been fully recorded in the claims.

Claims

1. A longitudinal watertight cable for an underwater detection robot, characterized in that: It comprises a cable core, a shielding layer (4), a water-blocking tape (5), an inner sheath (6), an armor layer (7), a first outer sheath (8), a tensile layer (9), and a second outer sheath (10); The cable core comprises a plurality of strands twisted into a cable core, each strand of the core comprises two groups of twisted conductors (1), each conductor (1) is coated with an insulating layer (2), and the two groups of conductors (1) in each strand of the core are twisted and encapsulated with a two-component water-blocking adhesive as a filler; The shielding layer (4) is wrapped around the entire cable core, and the gaps between the wire cores in the shielding layer are filled with a single-component water-blocking glue (3); The water-blocking tape (5) is a double-layer thin non-woven fabric, the middle of the interlayer of the double-layer thin non-woven fabric is coated with sodium polyacrylate, and the water-blocking tape (5) is wrapped around the outside of the shielding layer (4); The material of the inner protective layer (6) is foamed polyurethane, and the inner protective layer (6) is coated on the outside of the water blocking tape (5); The armor layer (7) is woven outside the inner protective layer (6); The material of the first outer protective layer (8) is foamed polyurethane, and the first outer protective layer (8) is coated on the outside of the armor layer (7); The material of the tensile layer (9) is liquid crystal polymer LCP fiber, and the tensile layer (9) is woven outside the first outer protective layer (8); The material of the second outer protective layer (10) is radiation cross-linked chlorosulfonated polyethylene, and the second outer protective layer (10) is coated outside the tensile layer (9).

2. The longitudinal watertight cable for an underwater exploration robot according to claim 1, characterized in that: The material of each conductor (1) is oxygen-free copper as a base, and a silver layer is plated outside the base.

3. The longitudinal watertight cable for an underwater exploration robot according to claim 1, characterized in that: The material of the insulating layer (2) is high-density polyethylene.

4. The longitudinal watertight cable for an underwater exploration robot according to claim 1, characterized in that: The single-component water-blocking adhesive (3) is prepared by mixing EVA resin, tackifying resin, wax and antioxidant.

5. The longitudinal watertight cable for an underwater exploration robot according to claim 1, characterized in that: The foamed polyurethane used as the material of the inner protective layer (6) and the first outer protective layer (8) is obtained by adding a nitrogen-based foaming agent to polyether polyurethane.

6. The longitudinal watertight cable for an underwater exploration robot according to claim 1, characterized in that: The material of the armor layer (7) is tinned copper wire.

7. The longitudinal watertight cable for an underwater exploration robot according to claim 1, characterized in that: The anti-tensile layer (9) is sandwiched between the first outer protective layer (8) and the second outer protective layer (10), and the bonding surfaces of the anti-tensile layer (9) and the first outer protective layer (8) and the second outer protective layer (10) are respectively coated with a single-component water-blocking adhesive.

8. The longitudinal watertight cable for an underwater exploration robot according to claim 1, characterized in that: The radiation cross-linked chlorosulfonated polyethylene used as the material of the second outer protective layer (10) is obtained by taking polyethylene as a matrix and introducing chlorine and chlorosulfonyl groups into the polyethylene molecular chain.

9. A process for preparing a longitudinal watertight cable for an underwater exploration robot as claimed in any one of claims 1 to 8, characterized in that: The following steps are involved: Step 1: Extruding an insulating layer (2) onto each conductor (1) by a high-temperature hot-melt high-pressure extrusion method; Step 2: Using a polycrystalline Hough mold to twist the conductors (1) in pairs to form a wire core, and when twisting the wire core, a two-component water-blocking adhesive is cast as a filler, and the two-component water-blocking adhesive is dried and cured in an infrared sintering furnace. When twisting, the twisting direction is left-handed, and a 30% back-twist rate constant tension is used for wire pay-off; Step 3: Use a nylon Huff mold to twist the strands of wire cores into a cable core. The overall twisting direction is left-handed, and a non-back-twisting active constant tension pay-off is used during twisting. Step 4, wrapping the shielding layer (4) around the cable core, and filling the gaps between the wire cores in the shielding layer (4) with a single-component water-blocking glue (3); Step 5: Wrap the water-blocking tape (5) around the shielding layer (4) in a reverse wrapping manner; Step 6, extruding and coating the inner protective layer (6) outside the water blocking tape (5); Step 7, cross-weaving the armor layer (7) outside the inner protective layer (6), applying hot melt adhesive to the gaps and surface of the armor layer (7) during weaving, and performing a rapid curing process on the hot melt adhesive; Step 8: The first outer sheath (8) and the second outer sheath (10) are covered on the outer side of the armor layer (7) by a double-layer co-extrusion method; a braiding machine and a glue coating machine are connected in series between the front and rear heads of the double-layer co-extrusion equipment; the tensile layer (9) is braided between the first outer sheath (8) and the second outer sheath (10) by the braiding machine; and the bonding surfaces of the tensile layer (9) and the first outer sheath (8) and the second outer sheath (10) are coated with a single-component water-blocking glue by the glue coating machine.

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