Production process for continuously producing high-toughness cable for oil platform

Abstract

The invention discloses a production process for continuously producing a high-toughness cable for an oil platform. According to the invention, through material innovation and process collaborative optimization, breakthrough of long-acting reliability and comprehensive performance of the cable in an extreme environment is realized. Firstly, an elastomer material system of the cable is based on a high and low temperature resistant double-substrate blending and dynamic crosslinking technology, so that the cable keeps high flexibility in a range of-60 DEG C to 125 DEG C, the tearing strength is remarkably improved, and the cable can bear more than 30 million times of reciprocating bending without cracking; the combination of the nano reinforced filler and the matte surface extinction process endows the outer layer of the cable with excellent wear resistance and scratch resistance, reduces the interference of surface reflection, and adapts to the complex marine operation environment. In addition, due to the synergistic effect of the halogen-free flame-retardant system and the ultraviolet light absorber, the long-acting safety of the cable under the conditions of flammability, strong corrosion and high ultraviolet radiation of an oil platform is ensured, and the requirements of environmental protection and durability are met.

Description

Technical Field

[0001] The invention belongs to the technical field of cables, and in particular relates to a production process for continuously producing high-toughness cables for oil platforms. Background Art

[0002] Oil platform cables are specialized cables designed specifically for offshore oil extraction and transportation, boasting exceptional resistance to oil, seawater corrosion, weathering, and mechanical strength. These cables are typically used to connect offshore oil platforms to onshore facilities, transmitting power, data, and control system signals to ensure the safety and efficiency of oil extraction and transportation. Oil platform cables utilize specialized materials and structural designs, such as an inner sheath made of oil-resistant rubber or specialized plastics, an outer sheath made of seawater-resistant materials, and conductors made of highly conductive materials with excellent flexibility to withstand the harsh offshore environment and complex installation conditions. Furthermore, oil platform cables must meet stringent fire, explosion, and tensile strength requirements to ensure stable and reliable operation even under extreme conditions. They are essential critical equipment in the offshore oil industry.

[0003] However, the traditional process uses a single base material and static cross-linking technology, resulting in insufficient resistance to high and low temperatures for the cable, and it is prone to brittle cracking under extreme temperature differences; it relies on halogen-containing flame retardants and simple mixing processes, which limits the corrosion resistance and environmental friendliness of the material, and the coating has poor adhesion, and the flame retardant layer is prone to peeling; the static vulcanization process is cumbersome, energy-intensive, and has a long production cycle, making it difficult to meet the needs of continuous and efficient processing. At the same time, the uneven dispersion of fillers leads to low tear strength, and the bending fatigue life is far lower than the harsh working conditions required by oil platforms. Summary of the Invention

[0004] The object of the present invention is to provide a production process for continuously producing high-toughness cables for oil platforms in order to solve the above-mentioned problems.

[0005] The technical solution adopted by the present invention is as follows: a production process for continuously producing high-toughness cables for oil platforms, the production process comprising the following steps: S1: First weigh the production raw materials, weighing: 65 parts by weight of thermoplastic polyester elastomer, 20 parts by weight of hydrogenated nitrile rubber, 8 parts by weight of modified carbon nanotubes, 5 parts by weight of nano-silica, 12 parts by weight of environmentally friendly plasticizer (DOTP), 3 parts by weight of composite heat stabilizer (organotin + metal oxide), 1.5 parts by weight of antioxidant Irganox1010, 0.8 parts by weight of ultraviolet absorber UV-326, 2 parts by weight of dynamic crosslinking agent dicumyl peroxide, 10 parts by weight of halogen-free phosphorus and nitrogen-based flame retardant, 3 parts by weight of fumed silica matting agent, and 0.5 parts by weight of silane coupling agent KH-550; The thermoplastic polyester elastomer is one of polybutylene terephthalate-polytetramethylene ether block copolymer, polyethylene terephthalate-polyether block copolymer or polybutylene adipate-polytetramethylene ether block copolymer.

[0006] The composite heat stabilizer is a combination of dibutyltin dilaurate and zinc oxide, dibutyltin maleate and magnesium oxide, or stannous octoate and calcium oxide.

[0007] The halogen-free phosphorus-nitrogen flame retardant is one of ammonium polyphosphate, melamine polyphosphate, or aluminum hypophosphite.

[0008] The environmentally friendly plasticizer is one of dioctyl terephthalate, diisononyl cyclohexanedicarboxylate, or trioctyl trimellitate.

[0009] The ultraviolet absorber is one of benzotriazole UV-326, benzophenone UV-531, or salicylate UV-9.

[0010] The dynamic crosslinking agent is one of dicumyl peroxide, di-tert-butyl peroxide, or benzoyl peroxide.

[0011] The dispersant is one of silane coupling agent KH-550, silane coupling agent KH-560, or titanate coupling agent NDZ-201; S2: The thermoplastic polyester elastomer and hydrogenated nitrile rubber are pre-dried separately to remove moisture and volatiles, and the pre-treated matrix materials are put into a twin-screw extruder and melt-blended at a set temperature to form a uniform matrix phase.

[0012] S3: Modified carbon nanotubes and nano-silica are injected simultaneously during the melt blending process, and high-speed shear dispersion is used to achieve uniform compounding of the nanofiller and the matrix.

[0013] S4: Add a dynamic cross-linking agent to the middle section of the extruder, and induce a dynamic cross-linking reaction by regulating the screw speed and temperature gradient to form a reversible molecular network structure.

[0014] S5: The composite melt is continuously extruded through a water-cooled die head and the surface is treated with a matte roller to give the outer layer of the cable matte wear-resistant properties.

[0015] S6: The extruded cable sheath is subjected to gradient cooling and shaping, and segmented temperature control is used to avoid internal stress concentration.

[0016] S7: Activate the cable surface through online plasma treatment technology to enhance the adhesion of subsequent flame retardant coating.

[0017] S8: Halogen-free flame retardant is applied synchronously on the continuous production line, and infrared curing technology is used to form a dense flame retardant protective layer.

[0018] S9: Conduct dynamic bending fatigue test and temperature cycle verification on the finished cables to ensure that the performance meets the standards before packaging.

[0019] In a preferred embodiment, in the step S2, the thermoplastic polyester elastomer and the hydrogenated nitrile rubber are respectively placed in a hot air circulation oven for pre-drying treatment, the oven temperature is set to 85±5 degrees Celsius, and the drying time is strictly controlled at 5±0.5 hours. A humidity sensor is equipped inside the oven to monitor the humidity in real time and maintain it below 0.03% to ensure that the free moisture and low molecular volatiles in the raw materials are completely removed. The dried material needs to be transferred to a sealed moisture-proof container and put into the next process within 30 minutes to avoid secondary moisture absorption. The moisture content of the raw material needs to be tested by a Karl Fischer moisture meter to ensure that it is less than 0.02% before proceeding to the next step.

[0020] In a preferred embodiment, in the step S2, the pre-dried matrix material is accurately measured by a loss-in-weight feeder and then put into a twin-screw extruder. The extruder is divided into five temperature control zones, which are set to 180 degrees Celsius, 190 degrees Celsius, 200 degrees Celsius, 210 degrees Celsius and 205 degrees Celsius from the feed end to the die head. The screw aspect ratio is 40: 1 and the rotation speed is 250 ± 10 revolutions per minute. During the melt blending process, the pressure fluctuations are monitored in real time by the melt pump to ensure that the pressure is stable within the range of 8 ± 0.5 MPa. The end of the extruder is equipped with a melt filter with a mesh size of 200 to intercept unmelted particles or impurities to ensure that the matrix continuous phase is defect-free.

[0021] In a preferred embodiment, in step S3, the modified carbon nanotubes and nano-silicon dioxide are pre-dispersed by a high-speed mixer and then injected into the high shear zone of the extruder at a rate of 0.5 ± 0.05 kg / h through a lateral weight loss feeder. The screw in this area is designed as a meshing block combination, the shear rate is increased to 7500 ± 500 seconds minus once, and the melt residence time is controlled at 60 ± 5 seconds. The filler dispersion state is monitored in real time by an online laser particle size analyzer to ensure that the particle size distribution D90 is ≤ 1 micron and there are no visible agglomerates. After dispersion is completed, the melt is further homogenized by a static mixer, and the temperature fluctuation range does not exceed ± 2 degrees Celsius.

[0022] In a preferred embodiment, in step S4, the dynamic crosslinking agent is added to the sixth reaction zone of the extruder by pulse injection via a high-pressure metering pump, with an injection pressure of 12±0.3 MPa and an injection rate of 0.8±0.05 liters / minute. The reaction zone temperature is set to 195±2 degrees Celsius, the screw speed is adjusted to 280 revolutions per minute, and a strong shear field and temperature gradient are formed by adjusting the angle and gap of the kneading block. The online rheometer detects the complex viscosity of the melt in real time, and the viscosity value needs to be stable within the range of 1500±200 Pa·s. The crosslinking density is verified by a nuclear magnetic resonance crosslinking analyzer, with a target value of 25±3%.

[0023] In a preferred embodiment, in step S5, the composite melt is extruded through a coat-hanger die with a die lip opening set to 2.0 ± 0.1 mm, and the melt flow rate is controlled at 15 ± 0.3 m / min by a gear pump. The matte roller surface is sandblasted to a roughness Ra of 1.6 ± 0.2 μm. Circulating cooling water is passed through the roller, and the water temperature is maintained at 55 ± 2 degrees Celsius. The roller pressure is adjusted to 0.8 ± 0.05 MPa by a pneumatic system. The surface gloss of the extruded cable is tested using a gloss meter to ensure that the 60° angle measurement value is ≤ 10 GU and there are no scratches or bubbles.

[0024] In a preferred embodiment, in step S6, the cable sheath enters a three-stage gradient cooling tank. The first stage is 70±2°C warm water spray cooling for 8±0.5 minutes; the second stage switches to 40±2°C circulating water immersion cooling for 10±1 minutes; and the third stage is 25±1°C cold water spray rapid shaping for 5±0.5 minutes. The water flow rate in the cooling tank is 0.5±0.05 m / s, ensuring a temperature difference of ≤5°C between the inner and outer layers of the cable. After cooling, the cable outer diameter tolerance must be controlled within ±0.05 mm, and the ovality must be ≤0.02 mm.

[0025] In a preferred embodiment, in step S7, the plasma treatment equipment uses a radio frequency power supply with a frequency of 13.56±0.01 MHz and a power density of 1.2±0.1 W / cm². The argon flow rate is set to 20±0.5 L / min, the treatment distance is 8±0.2 mm, and the cable travel speed is matched to 6±0.2 m / min. The treated surface energy must pass a dyne pen test and must reach 48±2 dynes. The surface micromorphology is then observed using a scanning electron microscope to ensure the formation of a uniform nanoscale pit structure with a depth of 200±50 nm.

[0026] In a preferred embodiment, in step S8, the halogen-free flame retardant slurry is compounded by ammonium polyphosphate and melamine cyanurate in a mass ratio of 3:1, and the solid content is adjusted to 45±1%. A slit coating head is used, the slit gap is set to 0.15±0.01 mm, and the coating pressure is 0.3±0.02 MPa. The infrared curing oven is divided into three zones for temperature control: the first zone is preheated at 120±2 degrees Celsius for 30 seconds, the second zone is cured at 150±2 degrees Celsius for 60 seconds, and the third zone is finally cured at 180±2 degrees Celsius for 90 seconds. After curing, the thickness of the flame retardant layer is 70±5 microns, and it meets the UL94 V-0 level through the vertical burning test, with an after-flame time of ≤3 seconds.

[0027] In a preferred embodiment, in step S9, the dynamic bending test adopts an ISO 17721 standard testing machine, with a bending radius of 6±0.1 times the outer diameter of the cable, a reciprocating frequency of 12±1 times / minute, and a full monitoring resistance change fluctuation of ≤±5%. The thermal cycle test box is set to -60±1 degrees Celsius (maintained for 30 minutes) to 125±1 degrees Celsius (maintained for 30 minutes) in alternating cycles, with a heating and cooling rate of 5 degrees Celsius / minute. The final product must pass a 2000V DC withstand voltage test (leakage current ≤0.5 mA) and a salt spray test (480 hours without corrosion). The winding tension is controlled by a servo motor at 25±2 Newtons, and the winding diameter error is ≤±1 mm.

[0028] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. In the present invention, through the coordinated optimization of material innovation and process, the long-term reliability and comprehensive performance of the cable in extreme environments have been achieved. First of all, its elastomeric material system is based on high and low temperature resistant dual matrix blending and dynamic cross-linking technology, which enables the cable to maintain high flexibility in the range of -60°C to 125°C, and the tear strength is significantly improved. It can withstand more than 30 million reciprocating bendings without cracking. The combination of nano-reinforced fillers and matte matte technology gives the outer layer of the cable excellent wear resistance and scratch resistance, while reducing surface reflection interference and adapting to complex operating environments at sea. In addition, the synergistic effect of the halogen-free flame retardant system and the UV absorber ensures the long-term safety of the cable in flammable, highly corrosive and high UV radiation scenarios on oil platforms, taking into account both environmental protection and durability requirements.

[0029] 2. This invention overcomes the limitations of traditional static vulcanization processes on material fluidity through innovative steps such as dynamic cross-linking induction and gradient cooling to achieve continuous and efficient production. The in-line integration of extrusion molding and plasma surface treatment avoids interfacial defects caused by multi-stage processing, ensuring dense adhesion of the flame-retardant coating. Segmented temperature control and tension winding technology further ensure cable dimensional stability and package uniformity, reducing physical damage during transportation and deployment. This overall process significantly shortens production cycles, reduces energy consumption, and reduces scrap rates while improving performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the process principle of the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0032] Example: Reference Figure 1 , A production process for continuously producing high-toughness cables for oil platforms, the production process comprising the following steps: S1: First weigh the production raw materials, weighing: 65 parts by weight of thermoplastic polyester elastomer, 20 parts by weight of hydrogenated nitrile rubber, 8 parts by weight of modified carbon nanotubes, 5 parts by weight of nano-silica, 12 parts by weight of environmentally friendly plasticizer (DOTP), 3 parts by weight of composite heat stabilizer (organotin + metal oxide), 1.5 parts by weight of antioxidant Irganox1010, 0.8 parts by weight of ultraviolet absorber UV-326, 2 parts by weight of dynamic crosslinking agent dicumyl peroxide, 10 parts by weight of halogen-free phosphorus and nitrogen-based flame retardant, 3 parts by weight of fumed silica matting agent, and 0.5 parts by weight of silane coupling agent KH-550; The thermoplastic polyester elastomer is one of polybutylene terephthalate-polytetramethylene ether block copolymer, polyethylene terephthalate-polyether block copolymer or polybutylene adipate-polytetramethylene ether block copolymer.

[0033] The composite heat stabilizer is a combination of dibutyltin dilaurate and zinc oxide, dibutyltin maleate and magnesium oxide, or stannous octoate and calcium oxide.

[0034] The halogen-free phosphorus-nitrogen flame retardant is one of ammonium polyphosphate, melamine polyphosphate, or aluminum hypophosphite.

[0035] The environmentally friendly plasticizer is one of dioctyl terephthalate, diisononyl cyclohexanedicarboxylate, or trioctyl trimellitate.

[0036] The ultraviolet absorber is one of benzotriazole UV-326, benzophenone UV-531, or salicylate UV-9.

[0037] The dynamic cross-linking agent is one of dicumyl peroxide, di-tert-butyl peroxide, or benzoyl peroxide.

[0038] The dispersant is one of silane coupling agent KH-550, silane coupling agent KH-560, or titanate coupling agent NDZ-201; S2: The thermoplastic polyester elastomer and hydrogenated nitrile rubber are pre-dried separately to remove moisture and volatiles, and the pre-treated matrix materials are put into a twin-screw extruder and melt-blended at a set temperature to form a uniform matrix phase.

[0039] S3: Modified carbon nanotubes and nano-silica are injected simultaneously during the melt blending process, and high-speed shear dispersion is used to achieve uniform compounding of the nanofiller and the matrix.

[0040] S4: Add a dynamic cross-linking agent to the middle section of the extruder, and induce a dynamic cross-linking reaction by regulating the screw speed and temperature gradient to form a reversible molecular network structure.

[0041] S5: The composite melt is continuously extruded through a water-cooled die head and the surface is treated with a matte roller to give the outer layer of the cable matte wear-resistant properties.

[0042] S6: The extruded cable sheath is subjected to gradient cooling and shaping, and segmented temperature control is used to avoid internal stress concentration.

[0043] S7: Activate the cable surface through online plasma treatment technology to enhance the adhesion of subsequent flame retardant coating.

[0044] S8: Halogen-free flame retardant is applied synchronously on the continuous production line, and infrared curing technology is used to form a dense flame retardant protective layer.

[0045] S9: Conduct dynamic bending fatigue test and temperature cycle verification on the finished cables to ensure that the performance meets the standards before packaging.

[0046] In step S2, the thermoplastic polyester elastomer and hydrogenated nitrile rubber are placed in a hot air circulation oven for pre-drying treatment. The oven temperature is set to 85±5 degrees Celsius, and the drying time is strictly controlled at 5±0.5 hours. A humidity sensor is equipped inside the oven to monitor the humidity in real time and maintain it below 0.03% to ensure that the free moisture and low molecular volatiles in the raw materials are completely removed. The dried material needs to be transferred to a sealed moisture-proof container and put into the next process within 30 minutes to avoid secondary moisture absorption. The moisture content of the raw material needs to be tested by a Karl Fischer moisture meter to ensure that it is less than 0.02% before proceeding to the next step.

[0047] In step S2, the pre-dried matrix material is accurately measured by a loss-in-weight feeder and then put into a twin-screw extruder. The extruder is divided into five temperature control zones, which are set to 180 degrees Celsius, 190 degrees Celsius, 200 degrees Celsius, 210 degrees Celsius and 205 degrees Celsius from the feed end to the die head. The screw aspect ratio is 40: 1 and the speed is 250 ± 10 revolutions per minute. During the melt blending process, the pressure fluctuations are monitored in real time by the melt pump to ensure that the pressure is stable within the range of 8 ± 0.5 MPa. The end of the extruder is equipped with a melt filter with a mesh size of 200 to intercept unmelted particles or impurities to ensure that the matrix continuous phase is defect-free.

[0048] In step S3, the modified carbon nanotubes and nano-silica are pre-dispersed by a high-speed mixer and injected into the high shear zone of the extruder at a rate of 0.5±0.05 kg / h through a lateral weight loss feeder. The screw in this area is designed as a meshing block combination, the shear rate is increased to 7500±500 seconds minus once, and the melt residence time is controlled at 60±5 seconds. The filler dispersion state is monitored in real time by an online laser particle size analyzer to ensure that the particle size distribution D90 is ≤1 micron and there are no visible agglomerates. After dispersion is completed, the melt is further homogenized by a static mixer, and the temperature fluctuation range does not exceed ±2 degrees Celsius.

[0049] In step S4, a dynamic crosslinker is pulsed into the sixth reaction zone of the extruder via a high-pressure metering pump at an injection pressure of 12 ± 0.3 MPa and an injection rate of 0.8 ± 0.05 liters / minute. The reaction zone temperature is set to 195 ± 2 degrees Celsius, the screw speed is adjusted to 280 revolutions per minute, and a strong shear field and temperature gradient are created by adjusting the angle and gap of the kneading blocks. The melt complex viscosity is monitored in real time by an online rheometer, with the viscosity value required to be stable within the range of 1500 ± 200 Pa·s. The crosslink density is verified using a nuclear magnetic resonance (NMR) analyzer, with a target value of 25 ± 3%.

[0050] In step S5, the composite melt is extruded through a coat-hanger die with a die lip opening set to 2.0 ± 0.1 mm. The melt flow rate is controlled by a gear pump at 15 ± 0.3 m / min. The matte roller surface is sandblasted to a roughness Ra of 1.6 ± 0.2 μm. Circulating cooling water is passed through the roller, and the water temperature is maintained at 55 ± 2 degrees Celsius. The roller pressure is adjusted to 0.8 ± 0.05 MPa using a pneumatic system. The surface gloss of the extruded cable is tested using a gloss meter to ensure that the 60° angle measurement value is ≤ 10 GU and that there are no scratches or bubbles.

[0051] In step S6, the cable sheath enters a three-stage gradient cooling tank. The first stage is a warm water spray cooling at 70±2°C for 8±0.5 minutes; the second stage switches to immersion cooling in circulating water at 40±2°C for 10±1 minutes; and the third stage is a rapid shaping cooling with cold water spray at 25±1°C for 5±0.5 minutes. The water flow rate in the cooling tank is 0.5±0.05 m / s, ensuring a temperature difference of ≤5°C between the inner and outer layers of the cable. After cooling, the cable outer diameter tolerance must be controlled within ±0.05 mm, and the ovality must be ≤0.02 mm.

[0052] In step S7, the plasma treatment equipment uses an RF power supply with a frequency of 13.56 ± 0.01 MHz and a power density of 1.2 ± 0.1 W / cm². The argon flow rate is set to 20 ± 0.5 liters / minute, the treatment distance is 8 ± 0.2 mm, and the cable travel speed is matched to 6 ± 0.2 m / minute. The treated surface energy must pass a dyne pen test and reach 48 ± 2 dynes. The surface micromorphology is then observed using a scanning electron microscope to ensure the formation of a uniform nanoscale pit structure with a depth of 200 ± 50 nm.

[0053] In step S8, a halogen-free flame-retardant slurry is compounded from ammonium polyphosphate and melamine cyanurate in a 3:1 mass ratio, with a solid content adjusted to 45±1%. A slit coating head is used, with the slit gap set to 0.15±0.01 mm and the coating pressure set to 0.3±0.02 MPa. The infrared curing oven is divided into three zones for temperature control: the first zone is preheated at 120±2 degrees Celsius for 30 seconds, the second zone is cured at 150±2 degrees Celsius for 60 seconds, and the third zone is cured at 180±2 degrees Celsius for 90 seconds. After curing, the flame-retardant layer has a thickness of 70±5 microns and meets the UL94 V-0 rating in the vertical combustion test, with an after-flame time of ≤3 seconds.

[0054] In step S9, the dynamic bending test uses an ISO 17721 standard testing machine, with a bending radius of 6±0.1 times the outer diameter of the cable, a reciprocating frequency of 12±1 times / minute, and full-process monitoring of resistance fluctuations ≤±5%. The thermal cycle test chamber is set to -60±1 degrees Celsius (maintained for 30 minutes) to 125±1 degrees Celsius (maintained for 30 minutes) in alternating cycles, with a heating and cooling rate of 5 degrees Celsius / minute. The final product must pass a 2000V DC withstand voltage test (leakage current ≤0.5 mA) and a salt spray test (480 hours without corrosion). The winding tension is controlled by a servo motor at 25±2 Newtons, and the winding diameter error is ≤±1 mm. Test example: Performance verification of high-toughness cables used in continuous production of oil platforms: Test items and methods: Mechanical properties test: Bending fatigue test: Based on ISO 17721, the reciprocating bending conditions of the drag chain cable on an oil platform are simulated, and the number of bends before the cable sheath cracks is recorded.

[0055] Tear strength test: ASTM D624 standard is used to test the tear strength of the cable sheath.

[0056] Environmental resistance test: High and low temperature cycle test: The cable is placed in a temperature chamber from -60℃ to 125℃ and cycled 100 times. Each cycle includes 30 minutes of high temperature and 30 minutes of low temperature. The surface is observed for cracking or deformation.

[0057] Salt spray corrosion test: Based on ASTM B117 standard, simulates marine environment to test the corrosion resistance of cable surface.

[0058] Flame retardant and safety performance test: Vertical burning test: Determines the flame retardancy of cables according to UL94 V-0 standard.

[0059] UV aging test: Simulates marine UV radiation in a UV aging chamber for 500 hours to assess surface chalking or cracking.

[0060] The experimental results are shown in the table below: From the experimental results we can know: In this invention, through innovative technologies such as dynamic cross-linking process, nano-filler reinforcement and plasma surface treatment, the bending fatigue resistance (≥32 million times) and tear strength (32.5MPa) of the cable are significantly improved, far exceeding the level of traditional processes. In extreme high and low temperature cycles and salt spray corrosion environments, the cable sheath does not crack or corrode, and the flame retardant performance reaches UL94 V-0 level, meeting the stringent requirements of oil platforms for long-term safety. In addition, the efficiency of the continuous production process is increased by 80%, and the halogen-free flame retardant system meets environmental protection standards, which comprehensively verifies the reliability and economic advantages of this process under extreme working conditions.

[0061] In the present invention, through the coordinated optimization of material innovation and process, the long-term reliability and comprehensive performance of the cable in extreme environments have been achieved. First of all, its elastomeric material system is based on high and low temperature resistant dual matrix blending and dynamic cross-linking technology, which enables the cable to maintain high flexibility in the range of -60°C to 125°C, and the tear strength is significantly improved. It can withstand more than 30 million reciprocating bendings without cracking. The combination of nano-reinforced fillers and matte matte technology gives the outer layer of the cable excellent wear resistance and scratch resistance, while reducing surface reflection interference and adapting to complex offshore operating environments. In addition, the synergistic effect of the halogen-free flame retardant system and the UV absorber ensures the long-term safety of the cable in flammable, highly corrosive and high UV radiation scenarios on oil platforms, taking into account both environmental protection and durability requirements.

[0062] In this invention, innovative steps such as dynamic cross-linking induction and gradient cooling for shaping overcome the limitations of traditional static vulcanization processes on material fluidity, enabling continuous and efficient production. The online integration of extrusion molding and plasma surface treatment avoids interfacial defects caused by multi-stage processing, ensuring dense adhesion of the flame-retardant coating. Segmented temperature control and tension winding technology further ensure cable dimensional stability and package uniformity, reducing physical damage during transportation and deployment. The overall process significantly shortens production cycles, reduces energy consumption, and reduces scrap rates while improving performance.

[0063] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprises" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device that includes 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 limitations, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device that includes the element.

[0064] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A production process for continuously producing high-toughness cables for oil platforms, characterized by: The production process comprises the following steps: S1: Weigh the raw materials first, and weigh: 65 parts by weight of thermoplastic polyester elastomer, 20 parts by weight of hydrogenated nitrile rubber, 8 parts by weight of modified carbon nanotubes, 5 parts by weight of nano-silica, 12 parts by weight of environmentally friendly plasticizer, 3 parts by weight of composite heat stabilizer, 1.5 parts by weight of antioxidant Irganox 1010, 0.8 parts by weight of ultraviolet absorber UV-326, 2 parts by weight of dynamic crosslinking agent dicumyl peroxide, 10 parts by weight of halogen-free phosphorus-nitrogen flame retardant, 3 parts by weight of fumed silica matting agent, and 0.5 parts by weight of silane coupling agent KH-550; The thermoplastic polyester elastomer is one of polybutylene terephthalate-polytetramethylene ether block copolymer, polyethylene terephthalate-polyether block copolymer or polybutylene adipate-polytetramethylene ether block copolymer; The composite heat stabilizer is a combination of dibutyltin dilaurate and zinc oxide, dibutyltin maleate and magnesium oxide, or stannous octoate and calcium oxide; The halogen-free phosphorus-nitrogen flame retardant is one of ammonium polyphosphate, melamine polyphosphate, or aluminum hypophosphite; The environmentally friendly plasticizer is one of dioctyl terephthalate, diisononyl cyclohexanedicarboxylate, or trioctyl trimellitate; The ultraviolet absorber is one of benzotriazole UV-326, benzophenone UV-531, or salicylate UV-9; The dynamic crosslinking agent is one of dicumyl peroxide, di-tert-butyl peroxide, or benzoyl peroxide; The dispersant is one of silane coupling agent KH-550, silane coupling agent KH-560, or titanate coupling agent NDZ-201; S2: pre-drying the thermoplastic polyester elastomer and hydrogenated nitrile rubber to remove moisture and volatiles, feeding the pre-treated matrix materials into a twin-screw extruder, and melt-blending them at a set temperature to form a uniform matrix phase; S3: Synchronously injecting modified carbon nanotubes and nano-silica during the melt blending process, and achieving uniform compounding of the nanofiller and the matrix through high-speed shear dispersion; S4: adding a dynamic crosslinking agent to the middle section of the extruder, and inducing a dynamic crosslinking reaction by regulating the screw speed and temperature gradient to form a reversible molecular network structure; S5: The composite melt is continuously extruded through a water-cooled die head and subjected to a matte matte roller surface treatment to give the outer layer of the cable a matte wear-resistant property; S6: Gradual cooling and shaping of the extruded cable sheath is performed, and segmented temperature control is adopted to avoid internal stress concentration; S7: Activate the cable surface through online plasma treatment technology to enhance the adhesion of subsequent flame retardant coating; S8: Halogen-free flame retardant is applied synchronously on the continuous production line, and infrared curing technology is used to form a dense flame retardant protective layer; S9: Conduct dynamic bending fatigue test and temperature cycle verification on the finished cables to ensure that the performance meets the standards before packaging.

2. The process for continuously producing high-toughness cables for oil platforms according to claim 1, characterized in that: In step S2, the thermoplastic polyester elastomer and the hydrogenated nitrile rubber are respectively placed in a hot air circulation oven for pre-drying treatment, the oven temperature is set to 85±5 degrees Celsius, and the drying time is strictly controlled to 5±0.5 hours; a humidity sensor is installed inside the oven to monitor the humidity in real time and maintain it below 0.03% to ensure that free moisture and low-molecular volatiles in the raw materials are completely removed; the dried material needs to be transferred to a sealed moisture-proof container and put into the next process within 30 minutes to avoid secondary moisture absorption; the moisture content of the raw material needs to be tested by a Karl Fischer titrator to ensure that it is less than 0.02% before proceeding to the next step.

3. The process for continuously producing high-toughness cables for oil platforms according to claim 1, characterized in that: In step S2, the pre-dried matrix material is accurately measured by a loss-in-weight feeder and then fed into a twin-screw extruder; the extruder is divided into five temperature control zones, which are set to 180 degrees Celsius, 190 degrees Celsius, 200 degrees Celsius, 210 degrees Celsius and 205 degrees Celsius from the feed end to the die head, respectively. The screw aspect ratio is 40:1 and the speed is 250±10 revolutions per minute; during the melt blending process, the pressure fluctuation is monitored in real time by the melt pump to ensure that the pressure is stable within the range of 8±0.5 MPa; the end of the extruder is equipped with a melt filter with a mesh size of 200 to intercept unmelted particles or impurities to ensure that the matrix continuous phase is defect-free.

4. The process for continuously producing high-toughness cables for oil platforms according to claim 1, characterized in that: In step S3, the modified carbon nanotubes and nano-silica are pre-dispersed in a high-speed mixer and then fed into the high shear zone of the extruder at a rate of 0.5±0.05 kg / h through a lateral loss-in-weight feeder; the screw in this zone is designed as a meshing block combination, the shear rate is increased to 7500±500 seconds minus one, and the melt residence time is controlled at 60±5 seconds; the filler dispersion state is monitored in real time by an online laser particle size analyzer to ensure that the particle size distribution D90 is ≤1 micron and there are no visible agglomerates; After dispersion is completed, the melt is further homogenized by a static mixer, and the temperature fluctuation range does not exceed ±2 degrees Celsius.

5. The process for continuously producing high-toughness cables for oil platforms according to claim 1, characterized in that: In step S4, the dynamic crosslinking agent is added to the sixth reaction zone of the extruder by pulse injection through a high-pressure metering pump, with an injection pressure of 12±0.3 MPa and an injection rate of 0.8±0.05 liters / minute; the reaction zone temperature is set to 195±2 degrees Celsius, the screw speed is adjusted to 280 revolutions per minute, and a strong shear field and temperature gradient are formed by adjusting the angle and gap of the kneading block; the melt complex viscosity is detected in real time by an online rheometer, and the viscosity value must be stable within the range of 1500±200 Pa·s. The crosslinking density is verified by a nuclear magnetic resonance crosslinking analyzer, with a target value of 25±3%.

6. The process for continuously producing high-toughness cables for oil platforms according to claim 1, characterized in that: In step S5, the composite melt is extruded through a coat-hanger die, the die lip opening is set to 2.0±0.1 mm, and the melt flow rate is controlled at 15±0.3 m / min by a gear pump; the matte matte roller surface is sandblasted, with a roughness Ra of 1.6±0.2 μm, circulating cooling water is passed into the roller, the water temperature is maintained at 55±2 degrees Celsius, and the roller pressure is adjusted to 0.8±0.05 MPa by a pneumatic system; the surface gloss of the extruded cable needs to be tested by a gloss meter to ensure that the 60° angle measurement value is ≤10 GU and there are no scratches or bubbles.

7. The process for continuously producing high-toughness cables for oil platforms according to claim 1, characterized in that: In step S6, the cable sheath enters a three-stage gradient cooling tank, the first stage is 70±2 degrees Celsius warm water spray cooling, the cooling time is 8±0.5 minutes; the second stage is switched to 40±2 degrees Celsius circulating water immersion cooling, the time is 10±1 minutes; the third stage is 25±1 degrees Celsius cold water spray rapid shaping, the time is 5±0.5 minutes; the water flow rate in the cooling tank is 0.5±0.05 m / s, ensuring that the temperature difference between the inner and outer layers of the cable is ≤5 degrees Celsius; after cooling, the outer diameter tolerance of the cable needs to be controlled within ±0.05 mm, and the ovality is ≤0.02 mm.

8. The process for continuously producing high-toughness cables for oil platforms according to claim 1, characterized in that: In step S7, the plasma treatment equipment uses a radio frequency power supply with a frequency of 13.56±0.01 MHz and a power density of 1.2±0.1 W / cm2; the argon flow rate is set to 20±0.5 L / min, the treatment distance is 8±0.2 mm, and the cable travel speed is matched to 6±0.2 m / min; the surface energy after treatment can pass the dyne pen test and must reach 48±2 dynes, and the surface micromorphology is observed by a scanning electron microscope to ensure the formation of a uniform nanoscale pit structure with a depth of 200±50 nm.

9. The process for continuously producing high-toughness cables for oil platforms according to claim 1, characterized in that: In step S8, the halogen-free flame retardant slurry is compounded by ammonium polyphosphate and melamine cyanurate in a mass ratio of 3:1, and the solid content is adjusted to 45±1%; a slit coating head is used, the slit gap is set to 0.15±0.01 mm, and the coating pressure is 0.3±0.02 MPa; the infrared curing furnace is divided into three zones for temperature control, the first zone is preheated at 120±2 degrees Celsius for 30 seconds, the second zone is cured at 150±2 degrees Celsius for 60 seconds, and the third zone is finally cured at 180±2 degrees Celsius for 90 seconds; the thickness of the flame retardant layer after curing is 70±5 microns, and it passes the vertical burning test to reach UL94 V-0 level, and the afterflame time is ≤3 seconds.

10. The process for continuously producing high-toughness cables for oil platforms according to claim 1, characterized in that: In step S9, the dynamic bending test uses an ISO 17721 standard testing machine, with a bending radius of 6±0.1 times the outer diameter of the cable, a reciprocating frequency of 12±1 times / minute, and a resistance change fluctuation of ≤±5% throughout the monitoring process; the thermal cycle test chamber is set to alternately cycle from -60±1 degrees Celsius to 125±1 degrees Celsius, with a heating and cooling rate of 5 degrees Celsius / minute; the final product must pass a 2000 V DC withstand voltage test and a salt spray test, the winding tension is controlled by a servo motor at 25±2 Newtons, and the winding diameter error is ≤±1 mm.

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