Temperature-resistant and high-pressure-resistant distributed optical cable for logging and processing method thereof

Abstract

The invention discloses a temperature-resistant and high-pressure-resistant distributed optical cable for logging and a processing method thereof. The temperature-resistant and high-pressure-resistant distributed optical cable for well logging comprises optical fiber cores, a high-temperature-resistant coating, a reinforcing layer, a hardness enhancing layer, a metal armor layer and an outer sheath which are sequentially arranged from inside to outside, the number of the optical fiber cores is multiple, preferably nine, and the nine optical fiber cores are formed by tightly combining three optical fiber cores in an inner annular array and six optical fiber cores outside. The peripheries of the optical fiber cores are uniformly coated with a high-temperature-resistant coating, the optical fiber cores are mutually twisted and connected and are wrapped with a reinforcing layer, the reinforcing layer is wrapped with a hardness enhancing layer, the hardness enhancing layer is wrapped with a metal armor layer, and the metal armor layer is wrapped with an outer sheath. The optical cable prepared by the method has excellent temperature resistance, high pressure resistance and mechanical strength.

Description

Technical Field

[0001] The invention belongs to the technical field of optical cable preparation, and in particular relates to a temperature-resistant and high-pressure-resistant distributed optical cable for well logging and a processing method thereof. Background Art

[0002] In the process of oil exploration and development, logging operations are a key link in obtaining formation information and evaluating the scale and reserves of oil and gas reservoirs. Traditional logging methods rely on various electronic sensors and cables, but these devices are often limited by the harsh environment of high temperature, high pressure, high corrosion, etc., resulting in reduced measurement accuracy and even equipment damage. Therefore, it is particularly important to develop a new logging technology that can adapt to extreme environments and has excellent performance. The distributed optical cable technology for logging that is resistant to temperature and high pressure has emerged. This optical cable is made of special optical fiber materials and has significant characteristics such as high temperature resistance, high pressure resistance, corrosion resistance, and resistance to electromagnetic interference from formations. As a sensing element, optical fiber can perform continuous and real-time measurements over the entire length of the optical cable without the need to set discrete sensors at predetermined points. This distributed sensing technology not only improves the accuracy and reliability of the measurement, but also greatly simplifies the operation process of logging operations.

[0003] Patent CN216697906U discloses a high-voltage, heat-resistant and waterproof cable, comprising four cable cores and an external protective structure, wherein the outer side of the cable core is provided with an internal protective structure, and the external protective structure is provided on the outer side of the internal protective structure; the external structure comprises an outer shell sleeved between the outer layers of the four cable cores, the inner side of the outer shell is fixedly connected with a first flame-retardant layer, the inner side of the first flame-retardant layer is fixedly connected with a waterproof layer, the inner side of the waterproof layer is fixedly connected with a thermal insulation layer, and the inner side of the thermal insulation layer is fixedly connected with a second filling layer. The cable prepared by this method has a flame-retardant function and avoids aging caused by high temperature, but the temperature resistance, high-voltage resistance and mechanical properties of the cable prepared by this method still have room for improvement. Summary of the invention

[0004] The object of the present invention is to provide a distributed optical cable for logging that is resistant to heat and high pressure and a processing method thereof, so as to solve the technical problems of poor temperature resistance, high pressure resistance and mechanical properties of the cable in the prior art.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a temperature-resistant and high-pressure resistant distributed optical cable for logging, comprising an optical fiber core, a high-temperature resistant coating, a reinforcement layer, a hardness enhancement layer, a metal armor layer and an outer sheath which are arranged in sequence from the inside to the outside, wherein a plurality of optical fiber cores are provided, the outer periphery of the optical fiber cores is uniformly coated with a high-temperature resistant coating, the optical fiber cores are twisted and connected to each other and are wrapped with a reinforcement layer on the outside, a hardness enhancement layer is wrapped on the outside of the reinforcement layer, a metal armor layer is wrapped on the outside of the hardness enhancement layer, and an outer sheath is wrapped on the outside of the metal armor layer.

[0007] Preferably, the method for preparing the high temperature resistant coating material comprises the following steps:

[0008] Q1: 2-amino-3-hydroxymethylpyridine and polyoxymethylene are added to N,N-dimethylformamide and mixed, heated and stirred, and then heated to react. After the reaction is completed, the product is added to distilled water, solids are precipitated, filtered, and dried to obtain an intermediate monomer; the intermediate monomer and phthalic anhydride are added to a container filled with N,N-dimethylformamide, and then triethylamine is added, and the reaction is carried out under a nitrogen atmosphere to obtain a monomer;

[0009] Q2: Add 2-aminodiphenylamine and sodium hydride to N,N-dimethylformamide, stir at room temperature, then add 4-fluoronitrobenzene, continue to stir at room temperature to react, after the reaction is completed, add to distilled water to quench the reaction, there is precipitation, suction filtration, dissolution, washing, drying, filtering, concentration, vacuum drying to obtain a crude product; add the crude product to ethanol to dissolve, then add palladium / carbon and hydrazine hydrate, heat and stir to react, after the reaction is completed, cool, dilute, filter, wash, separate, dry the organic phase, filter, concentrate, vacuum dry, purify to obtain a solid;

[0010] Q3: Add the monomer and solid matter into N,N-dimethylformamide in sequence, heat and stir to react, and after the reaction is completed, filter, wash, purify and dry to obtain a high temperature resistant coating material.

[0011] In the above process, the synthesis reaction formula of the high temperature resistant coating material is as follows:

[0012]

[0013] The results of mass spectrometry analysis of the intermediate monomer are: m / z: 408.19 (100.0%), 409.19 (24.9%), 410.20 (3.2%); the results of mass spectrometry analysis of the monomer are: m / z: 852.24 (100.0%), 853.24 (51.3%), 854.25 (12.0%), 854.24 (3.6%), 855.25 (3.1%) ; The results of mass spectrometry analysis of the crude product were: m / z: 547.15 (100.0%), 548.15 (34.5%), 549.16 (5.2%), 549.15 (1.8%); The results of mass spectrometry analysis of the solid were: m / z: 457.23 (100.0%), 458.23 (32.8%), 459.23 (5.7%), 458.22 (1.8%).

[0014] Preferably, in Q1, the amount ratio of 2-amino-3-hydroxymethylpyridine, polyoxymethylene, N,N-dimethylformamide and distilled water is (1.5-1.8) g: (0.9-1.2) g: (20-24) mL: (200-230) mL, the heating and stirring temperature is 100-120°C, the stirring time is 2-3 h, the heating reaction temperature is 140-150°C, and the reaction time is 7-9 h; the amount ratio of the intermediate monomer, phthalic anhydride, N,N-dimethylformamide and triethylamine is (2.13-2.35) g: (1.85-2.02) g: (10-20) mL: (0.2-0.25) g, and the reaction time is 20-24 h.

[0015] Preferably, in Q2, the amount ratio of 2-aminodiphenylamine, sodium hydride, N,N-dimethylformamide and 4-fluoronitrobenzene is (3.22-3.56) g: (1.05-1.38) g: (32-46) mL: (3.18-3.59) g, the stirring time at room temperature is 1-2 h, the stirring reaction time at room temperature is continued for 5-7 h, the mixture is dissolved with dichloromethane, washed with saturated sodium chloride solution, and dried with anhydrous sodium sulfate; the amount ratio of crude product, ethanol, palladium / carbon and hydrazine hydrate is (2.12-2.46) g: (40-60) mL: (1.12-1.54) g: (5.89-6.16) mL, the heating and stirring reaction temperature is 80-85°C, the reaction time is 4-6 h, the mixture is diluted with dichloromethane, washed with saturated sodium chloride solution, and the organic phase is dried with anhydrous sodium sulfate.

[0016] Preferably, in Q3, the usage ratio of monomer, solid and N,N-dimethylformamide is (2.04-2.65) g: (2.43-2.96) g: (10-15) mL, the heating temperature is 110-140° C., and the reaction time is 8-10 h.

[0017] Preferably, the method for preparing the outer sheath material comprises the following steps:

[0018] S1: Add dopamine hydrochloride and imidazole to a container filled with dichloromethane, stir magnetically, then dropwise add triethylsilyl chloride, stir at room temperature for reaction, and after the reaction is completed, dilute, extract, wash, dry, and rotary evaporate to obtain intermediate 1;

[0019] S2: adding intermediate 1 and triethylamine to a container filled with tetrahydrofuran, then dissolving diphenyl chlorophosphate in tetrahydrofuran and slowly adding the mixture dropwise to the container, stirring the mixture magnetically to react, and after the reaction is completed, blowing off, diluting, extracting, washing, drying, and rotary evaporation are performed to obtain intermediate 2;

[0020] S3: Add intermediate 2 to ethanol, then slowly add hydrochloric acid, stir at room temperature, rotary evaporate, and purify to obtain intermediate 3; add intermediate 3, 4,4'-difluorobenzophenone, potassium carbonate, toluene and N-methylpyrrolidone to a container, heat and stir under reflux, continue to heat and react, after the reaction is completed, add to distilled water, filter, vacuum dry, dissolve, precipitate, wash, and vacuum dry to obtain an outer sheath material.

[0021] In the above process, the synthetic reaction formula of the outer sheath material is as follows:

[0022]

[0023] The results of mass spectrometry analysis of intermediate 1 were: m / z: 381.25 (100.0%), 382.26 (22.2%), 382.25 (10.5%), 383.25 (9.3%), 383.26 (2.8%), 384.25 (1.9%); the results of mass spectrometry analysis of intermediate 2 were: m / z: 613.28 (100.0%), 614.28 (45.1%), 615.28 (10.7%), 615.29 (7.1%), 616.28 (2.9%), 616.29 (1.7%); the results of mass spectrometry analysis of intermediate 3 were: m / z: 385.11 (100.0%), 386.11 (22.1%), 387.11 (3.3%).

[0024] Preferably, in S1, the dosage ratio of dopamine hydrochloride, imidazole, dichloromethane and triethylsilyl chloride is (3.2-4.6) g: (5.12-5.98) g: (60-80) mL: (7.63-8.02) g, the stirring reaction time is 12-16 h, diluted with dichloromethane, extracted and washed with 1 mol / L sodium bicarbonate aqueous solution, deionized water and saturated sodium chloride solution, and dried with anhydrous sodium sulfate.

[0025] Preferably, in S2, the usage ratio of intermediate 1, triethylamine and diphenyl chlorophosphate is (7.1-8.6) g: (2.8-3.6) g: (5.12-5.98) g, the magnetic stirring reaction time is 12-16 h, ethyl acetate is added for dilution, extraction and washing are carried out with 1 mol / L ammonium chloride solution and saturated sodium chloride solution, and drying is carried out with anhydrous sodium sulfate.

[0026] Preferably, in S3, the amount ratio of intermediate 2, ethanol and hydrochloric acid is (8.12-9.35) g: (20-25) mL: (10-12) mL, the concentration of hydrochloric acid is 1 mol / L, and the stirring time at room temperature is 24-36 h; the amount ratio of intermediate 3, 4,4'-difluorobenzophenone, potassium carbonate, toluene and N-methylpyrrolidone is (18-22) g: (11.8-13.6) g: (13-19) g: (68-76) mL: (200-230) mL, the heating stirring reflux temperature is 140-150° C., the reflux time is 1-2 h, the heating reaction temperature is 170-190° C., and the reaction time is 4-6 h.

[0027] Preferably, the method for processing the temperature-resistant and high-pressure-resistant distributed optical cable for logging comprises the following steps:

[0028] Step 1: Wipe the surface of the optical fiber core with anhydrous ethanol, evenly apply the high-temperature resistant coating on the surface of the optical fiber core, solidify, twist, and then insert the twisted optical fiber core containing the high-temperature resistant coating into the reinforcement layer, fill with water-blocking yarn, and seal and weld;

[0029] Step 2: Evenly wind the aramid fiber on the surface of the stainless steel tube, then coat it with epoxy resin glue and solidify it to obtain a hardness enhancement layer, then wind it with stainless steel wire, and obtain a metal armor layer after annealing. Melt the outer sheath material, extrude it, and fix it on the outer layer of the metal armor layer to obtain a temperature-resistant and high-pressure resistant distributed optical cable for well logging.

[0030] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0031] 1. The present invention first uses 2-amino-3-hydroxymethylpyridine, polyformaldehyde, phthalic anhydride, 2-aminodiphenylamine and 4-fluoronitrobenzene as raw materials to prepare a high-temperature resistant coating material, and then uses dopamine hydrochloride, triethylsilyl chloride, diphenyl chlorophosphate, hydrochloric acid and 4,4'-difluorobenzophenone as raw materials to prepare an outer sheath material, which is added to the optical cable to effectively improve the pressure resistance, temperature resistance and flame retardant properties of the optical cable.

[0032] 2. The present invention uniformly coats the prepared high-temperature resistant coating material on the surface of the optical fiber core, which can effectively improve the high-temperature resistance and mechanical properties of the optical cable. The triazine ring contained in the high-temperature resistant coating material has a highly conjugated directional structure, the electron cloud in the molecule is evenly distributed, and the chemical bond energy is high. It can effectively disperse thermal stress at high temperatures, hinder the breakage of molecular chains, and significantly improve the high-temperature resistance of the optical cable. The polar effect of the amide bonds in the molecular chain of the high-temperature resistant coating material and the hydrogen bond network form a dense cross-linking structure, which enhances the interaction between molecular chains, inhibits the slippage of molecular chains at high temperatures, and improves the glass transition temperature and thermal stability, so that the optical cable can withstand high temperature environments. The structure remains stable without softening, decomposition or bubbles, ensuring the reliability of optical cable signal transmission; the triazine ring in the high temperature resistant coating material is embedded in the polyamide main chain as a rigid structural unit, which improves the elastic modulus and tensile strength of the material by limiting the flexibility of the molecular chain. At the same time, its planar structure can induce the molecular chains to arrange in order to form a structure similar to a "physical cross-linking point" to enhance the creep resistance. The ester bonds contained as polar groups can interact with the polyamide main chain through hydrogen bonds or ionic bonds to form a dynamic and reversible physical cross-linking network, so that it can dissipate energy through bond breaking and recombination when subjected to force, giving the material good toughness and impact resistance.

[0033] 3. The present invention applies the prepared outer sheath material to the optical cable, which can effectively improve its high temperature resistance, mechanical properties and flame retardant properties. The main chain of the outer sheath material is composed of alternating ether bonds, ketone bonds and rigid aromatic rings. The ether bonds provide flexibility of the molecular chain, while the ketone bonds and the aromatic rings form a highly rigid molecular skeleton through the conjugation effect, which hinders the free rotation of the molecular chain. The π-π stacking effect of the aromatic rings enhances the intermolecular force and improves the thermal stability. The aromatic rings and polar ketone bonds in the outer sheath material form a strong dipole-dipole interaction, which promotes the formation of a crystalline region. The crystalline region serves as a physical crosslinking point to disperse the The flexibility of the ether bond allows the molecular chain to deform locally and absorb energy when subjected to stress, while the rigid skeleton provides overall deformation resistance, giving the optical cable a high fatigue life; at the same time, the phosphate contained in the outer sheath material has heat absorption and heat insulation effects, which can absorb part of the heat generated by combustion, effectively reduce the surface temperature of the optical cable, thereby slowing down the combustion rate. The generated water vapor can also dilute the surrounding combustion-supporting gas, reduce the oxygen concentration in the combustion area, and further inhibit combustion. The phosphate substance can also form a protective layer on the surface of the optical cable to isolate oxygen and heat and prevent further spread of combustion. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 It is a cross-sectional schematic diagram of the temperature-resistant and high-pressure-resistant distributed optical cable for well logging prepared by the present invention.

[0036] Description of the drawings: 1. Optical fiber core; 2. High temperature resistant coating; 3. Stainless steel tube; 4. Hardness enhancement layer; 5. Metal armor layer; 6. Outer sheath. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Example 1: See Figure 1 As shown, a temperature-resistant and high-pressure resistant distributed optical cable for logging of the present embodiment comprises an optical fiber core 1, a reinforcement layer 3, a hardness enhancement layer 4, a metal armor layer 5 and an outer sheath 6 which are arranged in sequence from the inside to the outside, wherein a plurality of optical fiber cores are provided, preferably nine, and the nine are formed by three inner annular arrays and six outer ones being tightly combined, the outer periphery of the optical fiber core 1 is evenly coated with a high-temperature resistant coating 2, the optical fiber cores 1 are twisted and connected to each other and are wrapped with a reinforcement layer 3 on the outside, the outer side of the reinforcement layer 3 is wrapped with a hardness enhancement layer 4, the outer side of the hardness enhancement layer 4 is wrapped with a metal armor layer 5, and the outer side of the metal armor layer 5 is wrapped with an outer sheath 6.

[0039] Embodiment 2: This embodiment discloses a method for preparing a high temperature resistant coating material, comprising the following steps:

[0040] Q1: 1.65 g of 2-amino-3-hydroxymethylpyridine and 1.1 g of polyoxymethylene were added to 22 mL of N,N-dimethylformamide and mixed, heated at 110°C with stirring for 3 h, then heated to 145°C for reaction for 8 h. After the reaction, the product was added to 215 mL of distilled water, solid precipitated, filtered, and dried to obtain an intermediate monomer; 2.24 g of the intermediate monomer and 1.93 g of phthalic anhydride were added to a container containing 15 mL of N,N-dimethylformamide, and then 0.22 g of triethylamine was added. The mixture was reacted for 24 h under a nitrogen atmosphere to obtain a monomer;

[0041] Q2: Add 3.39 g of 2-aminodiphenylamine and 1.21 g of sodium hydride to 39 mL of N,N-dimethylformamide, stir at room temperature for 2 h, then add 3.39 g of 4-fluoronitrobenzene, continue stirring at room temperature for 6 h, after the reaction is completed, add to distilled water to quench the reaction, a precipitate is precipitated, filter, dissolve with dichloromethane, wash with saturated sodium chloride solution, dry with anhydrous sodium sulfate, filter, concentrate, and vacuum dry to obtain a crude product; add 2.29 g of the crude product to 50 mL of ethanol for dissolution, then add 1.33 g of palladium / carbon and 5.98 mL of hydrazine hydrate, heat and stir at 85 ° C for 6 h, after the reaction is completed, cool, dilute with dichloromethane, filter, wash with saturated sodium chloride solution, separate, dry the organic phase with anhydrous sodium sulfate, filter, concentrate, vacuum dry, purify, and obtain a solid;

[0042] Q3: 2.35 g monomer and 2.68 g solid were added to 12.5 mL N,N-dimethylformamide in sequence, heated and stirred at 120°C for 10 h. After the reaction, filtered, washed, purified and dried to obtain a high temperature resistant coating material.

[0043] This embodiment discloses a method for preparing an outer sheath material, comprising the following steps:

[0044] S1: 3.9 g dopamine hydrochloride and 5.55 g imidazole were added to a container containing 70 mL dichloromethane, and magnetic stirring was performed. Then 7.82 g triethylsilyl chloride was added dropwise, and the mixture was stirred at room temperature for 16 h. After the reaction was completed, the mixture was diluted with dichloromethane, extracted and washed with 1 mol / L sodium bicarbonate aqueous solution, deionized water and saturated sodium chloride solution, dried with anhydrous sodium sulfate, and rotary evaporated to obtain intermediate 1;

[0045] S2: 7.8 g of intermediate 1 and 3.2 g of triethylamine were added to a container containing 10 mL of tetrahydrofuran, and then 5.55 g of diphenyl chlorophosphate was dissolved in 10 mL of tetrahydrofuran and slowly added dropwise to the container. The reaction was stirred magnetically for 12 h. After the reaction was completed, the reaction was purged, ethyl acetate was added for dilution, and the mixture was extracted and washed with 1 mol / L ammonium chloride solution and saturated sodium chloride solution. The mixture was dried with anhydrous sodium sulfate and rotary evaporated to obtain intermediate 2;

[0046] S3: 8.73 g of intermediate 2 was added to 22.5 mL of ethanol, and then 11 mL of 1 mol / L hydrochloric acid was slowly added, and the mixture was stirred at room temperature for 36 h, and then rotary evaporated and purified to obtain intermediate 3; 20 g of intermediate 3, 12.2 g of 4,4'-difluorobenzophenone, 16 g of potassium carbonate, 72 mL of toluene and 215 mL of N-methylpyrrolidone were added to a container, heated and stirred at 145 ° C for 2 h, and then the temperature was continued to rise to 180 ° C for 6 h. After the reaction was completed, the mixture was added to distilled water, filtered, vacuum dried, dissolved, precipitated, washed, and vacuum dried to obtain an outer sheath material.

[0047] See also Figure 1 As shown, this embodiment discloses a method for processing a temperature-resistant and high-pressure-resistant distributed optical cable for logging, comprising the following steps:

[0048] Step 1: Wipe the surface of the optical fiber core 1 with anhydrous ethanol, evenly apply the high temperature resistant coating 2 material on the surface of the optical fiber core, solidify, twist, and then insert the twisted optical fiber core 1 containing the high temperature resistant coating 2 into the reinforcement layer 3, fill with water-blocking yarn, and seal and weld;

[0049] Step 2: Evenly wind the aramid fiber on the surface of the reinforcement layer 3, then coat it with epoxy resin glue and solidify it to obtain a hardness enhancement layer 4, which is then wound with stainless steel wire and annealed to obtain a metal armor layer 5. The outer sheath 6 material is melted, extruded, and fixed on the outer layer of the metal armor layer 5 to obtain a temperature-resistant and high-pressure resistant distributed optical cable for well logging.

[0050] Embodiment 3: This embodiment discloses a method for preparing a high temperature resistant coating material, comprising the following steps:

[0051] Q1: 1.5 g of 2-amino-3-hydroxymethylpyridine and 0.9 g of polyoxymethylene were added to 20 mL of N,N-dimethylformamide and mixed, heated at 110°C with stirring for 3 h, then heated to 145°C for reaction for 8 h. After the reaction, the product was added to 200 mL of distilled water, solid precipitated, filtered, and dried to obtain an intermediate monomer; 2.13 g of the intermediate monomer and 1.85 g of phthalic anhydride were added to a container containing 10 mL of N,N-dimethylformamide, and then 0.2 g of triethylamine was added, and the mixture was reacted under a nitrogen atmosphere to obtain a monomer;

[0052] Q2: Add 3.22g 2-aminodiphenylamine and 1.05g sodium hydride to 32mL N,N-dimethylformamide, stir at room temperature for 2h, then add 3.18g 4-fluoronitrobenzene, continue to stir at room temperature for 6h, after the reaction is completed, add to distilled water to quench the reaction, a precipitate is precipitated, filter, dissolve with dichloromethane, wash with saturated sodium chloride solution, dry with anhydrous sodium sulfate, filter, concentrate, and vacuum dry to obtain a crude product; add 2.12g crude product to 40mL ethanol for dissolution, then add 1.12g palladium / carbon and 5.89mL hydrazine hydrate, heat and stir at 85℃ for 6h, after the reaction is completed, cool, dilute with dichloromethane, filter, wash with saturated sodium chloride solution, separate, dry the organic phase with anhydrous sodium sulfate, filter, concentrate, vacuum dry, purify, and obtain a solid;

[0053] Q3: 2.04 g monomer and 2.43 g solid were added to 10 mL N,N-dimethylformamide in sequence, heated and stirred at 120°C for 10 h. After the reaction, the mixture was filtered, washed, purified and dried to obtain a high temperature resistant coating material.

[0054] This embodiment discloses a method for preparing an outer sheath material, comprising the following steps:

[0055] S1: 3.2 g dopamine hydrochloride and 5.12 g imidazole were added to a container containing 60 mL dichloromethane, and magnetic stirring was performed. Then 7.63 g triethylsilyl chloride was added dropwise, and the mixture was stirred at room temperature for 16 h. After the reaction was completed, the mixture was diluted with dichloromethane, extracted and washed with 1 mol / L sodium bicarbonate aqueous solution, deionized water and saturated sodium chloride solution, dried with anhydrous sodium sulfate, and rotary evaporated to obtain intermediate 1;

[0056] S2: 7.1 g of intermediate 1 and 2.8 g of triethylamine were added to a container containing 10 mL of tetrahydrofuran, and then 5.12 g of diphenyl chlorophosphate was dissolved in 10 mL of tetrahydrofuran and slowly added dropwise to the container. The reaction was stirred magnetically for 12 h. After the reaction was completed, the reaction was purged, ethyl acetate was added for dilution, and the mixture was extracted and washed with 1 mol / L ammonium chloride solution and saturated sodium chloride solution. The mixture was dried with anhydrous sodium sulfate and rotary evaporated to obtain intermediate 2.

[0057] S3: 8.12 g of intermediate 2 was added to 20 mL of ethanol, and then 10 mL of 1 mol / L hydrochloric acid was slowly added, and the mixture was stirred at room temperature for 36 h, and then rotary evaporated and purified to obtain intermediate 3; 18 g of intermediate 3, 11.8 g of 4,4'-difluorobenzophenone, 13 g of potassium carbonate, 68 mL of toluene and 200 mL of N-methylpyrrolidone were added to a container, heated and stirred at 145°C for 2 h, and then the temperature was raised to 180°C for 6 h. After the reaction was completed, the mixture was added to distilled water, filtered, vacuum dried, dissolved, precipitated, washed, and vacuum dried to obtain an outer sheath material.

[0058] See also Figure 1 As shown, this embodiment discloses a method for processing a temperature-resistant and high-pressure-resistant distributed optical cable for logging, comprising the following steps:

[0059] Step 1: Wipe the surface of the optical fiber core 1 with anhydrous ethanol, evenly apply the high temperature resistant coating 2 material on the surface of the optical fiber core, solidify, twist, and then insert the twisted optical fiber core 1 containing the high temperature resistant coating 2 into the reinforcement layer 3, fill with water-blocking yarn, and seal and weld;

[0060] Step 2: Evenly wind the aramid fiber on the surface of the reinforcement layer 3, then coat it with epoxy resin glue and solidify it to obtain a hardness enhancement layer 4, which is then wound with stainless steel wire and annealed to obtain a metal armor layer 5. The outer sheath 6 material is melted, extruded, and fixed on the outer layer of the metal armor layer 5 to obtain a temperature-resistant and high-pressure resistant distributed optical cable for well logging.

[0061] Embodiment 4: This embodiment discloses a method for preparing a high temperature resistant coating material, comprising the following steps:

[0062] Q1: 1.8 g of 2-amino-3-hydroxymethylpyridine and 1.2 g of polyoxymethylene were added to 24 mL of N, N-dimethylformamide and mixed, heated at 110 ° C with stirring for 3 h, and then heated to 145 ° C for reaction for 8 h. After the reaction, the product was added to 230 mL of distilled water, and solids were precipitated. The solids were filtered and dried to obtain an intermediate monomer; 2.35 g of the intermediate monomer and 2.02 g of phthalic anhydride were added to a container containing 20 mL of N, N-dimethylformamide, and then 0.25 g of triethylamine was added. The mixture was reacted under a nitrogen atmosphere to obtain a monomer;

[0063] Q2: Add 3.56g 2-aminodiphenylamine and 1.38g sodium hydride to 46mL N,N-dimethylformamide, stir at room temperature for 2h, then add 3.59g 4-fluoronitrobenzene, continue to stir at room temperature for 6h, after the reaction is completed, add to distilled water to quench the reaction, a precipitate is precipitated, filtered, dissolved with dichloromethane, washed with saturated sodium chloride solution, dried with anhydrous sodium sulfate, filtered, concentrated, and vacuum dried to obtain a crude product; 2.46g of the crude product is added to 60mL ethanol for dissolution, then 1.54g palladium / carbon and 6.16mL hydrazine hydrate are added, heated and stirred at 85℃ for 6h, after the reaction is completed, cool, dilute with dichloromethane, filter, wash with saturated sodium chloride solution, separate, dry the organic phase with anhydrous sodium sulfate, filter, concentrate, vacuum dry, purify, and obtain a solid;

[0064] Q3: 2.65 g of monomer and 2.96 g of solid were added to 15 mL of N,N-dimethylformamide in sequence, heated and stirred at 120°C for 10 h. After the reaction, the mixture was filtered, washed, purified and dried to obtain a high temperature resistant coating material.

[0065] This embodiment discloses a method for preparing an outer sheath material, comprising the following steps:

[0066] S1: 4.6 g dopamine hydrochloride and 5.98 g imidazole were added to a container containing 80 mL dichloromethane, and magnetic stirring was performed. Then 8.02 g triethylsilyl chloride was added dropwise, and the mixture was stirred at room temperature for 16 h. After the reaction was completed, the mixture was diluted with dichloromethane, extracted and washed with 1 mol / L sodium bicarbonate aqueous solution, deionized water and saturated sodium chloride solution, dried with anhydrous sodium sulfate, and rotary evaporated to obtain intermediate 1;

[0067] S2: 8.6 g of intermediate 1 and 3.6 g of triethylamine were added to a container containing 10 mL of tetrahydrofuran, and then 5.98 g of diphenyl chlorophosphate was dissolved in 10 mL of tetrahydrofuran and slowly added dropwise to the container. The reaction was stirred magnetically for 12 h. After the reaction was completed, the reaction was purged, ethyl acetate was added for dilution, and the mixture was extracted and washed with 1 mol / L ammonium chloride solution and saturated sodium chloride solution. The mixture was dried with anhydrous sodium sulfate and rotary evaporated to obtain intermediate 2;

[0068] S3: 9.35 g of intermediate 2 was added to 25 mL of ethanol, and then 12 mL of 1 mol / L hydrochloric acid was slowly added, stirred at room temperature for 36 h, and rotary evaporated to purify to obtain intermediate 3; 22 g of intermediate 3, 13.6 g of 4,4'-difluorobenzophenone, 19 g of potassium carbonate, 76 mL of toluene and 230 mL of N-methylpyrrolidone were added to a container, heated at 145 ° C, stirred and refluxed for 2 h, and continued to heat at 180 ° C for 6 h. After the reaction was completed, it was added to distilled water, filtered, vacuum dried, dissolved, precipitated, washed, and vacuum dried to obtain an outer sheath material.

[0069] See also Figure 1 As shown, this embodiment discloses a method for processing a temperature-resistant and high-pressure-resistant distributed optical cable for logging, comprising the following steps:

[0070] Step 1: Wipe the surface of the optical fiber core 1 with anhydrous ethanol, evenly apply the high temperature resistant coating 2 material on the surface of the optical fiber core, solidify, twist, and then insert the twisted optical fiber core 1 containing the high temperature resistant coating 2 into the reinforcement layer 3, fill with water-blocking yarn, and seal and weld;

[0071] Step 2: Evenly wind the aramid fiber on the surface of the reinforcement layer 3, then coat it with epoxy resin glue and solidify it to obtain a hardness enhancement layer 4, which is then wound with stainless steel wire and annealed to obtain a metal armor layer 5. The outer sheath 6 material is melted, extruded, and fixed on the outer layer of the metal armor layer 5 to obtain a temperature-resistant and high-pressure resistant distributed optical cable for well logging.

[0072] Embodiment 5: This embodiment discloses a method for preparing a high temperature resistant coating material, comprising the following steps:

[0073] Q1: 1.6 g of 2-amino-3-hydroxymethylpyridine and 1 g of polyoxymethylene were added to 21 mL of N,N-dimethylformamide and mixed, heated at 110°C with stirring for 3 h, then heated to 145°C for reaction for 8 h. After the reaction, the product was added to 210 mL of distilled water, solid precipitated, filtered, and dried to obtain an intermediate monomer; 2.31 g of the intermediate monomer and 1.87 g of phthalic anhydride were added to a container containing 12 mL of N,N-dimethylformamide, and then 0.23 g of triethylamine was added, and the mixture was reacted under a nitrogen atmosphere to obtain a monomer;

[0074] Q2: Add 3.27g 2-aminodiphenylamine and 1.11g sodium hydride to 35mL N,N-dimethylformamide, stir at room temperature for 2h, then add 3.24g 4-fluoronitrobenzene, continue to stir at room temperature for 6h, after the reaction is completed, add to distilled water to quench the reaction, a precipitate is precipitated, filter, dissolve with dichloromethane, wash with saturated sodium chloride solution, dry with anhydrous sodium sulfate, filter, concentrate, and vacuum dry to obtain a crude product; add 2.21g crude product to 45mL ethanol for dissolution, then add 1.23g palladium / carbon and 5.91mL hydrazine hydrate, heat and stir at 85℃ for 6h, after the reaction is completed, cool, dilute with dichloromethane, filter, wash with saturated sodium chloride solution, separate, dry the organic phase with anhydrous sodium sulfate, filter, concentrate, vacuum dry, purify, and obtain a solid;

[0075] Q3: 2.21 g monomer and 2.51 g solid were added to 11 mL N,N-dimethylformamide in sequence, heated and stirred at 120°C for 10 h. After the reaction, the mixture was filtered, washed, purified and dried to obtain a high temperature resistant coating material.

[0076] This embodiment discloses a method for preparing an outer sheath material, comprising the following steps:

[0077] S1: 3.5 g dopamine hydrochloride and 5.43 g imidazole were added to a container containing 65 mL dichloromethane, and magnetic stirring was performed. Then 7.71 g triethylsilyl chloride was added dropwise, and the mixture was stirred at room temperature for 16 h. After the reaction was completed, the mixture was diluted with dichloromethane, extracted and washed with 1 mol / L sodium bicarbonate aqueous solution, deionized water and saturated sodium chloride solution, dried with anhydrous sodium sulfate, and rotary evaporated to obtain intermediate 1;

[0078] S2: 7.4 g of intermediate 1 and 3 g of triethylamine were added to a container containing 10 mL of tetrahydrofuran, and then 5.31 g of diphenyl chlorophosphate was dissolved in 10 mL of tetrahydrofuran and slowly added dropwise to the container. The reaction was stirred magnetically for 12 h. After the reaction was completed, the reaction was purged, ethyl acetate was added for dilution, and the mixture was extracted and washed with 1 mol / L ammonium chloride solution and saturated sodium chloride solution. The mixture was dried with anhydrous sodium sulfate and rotary evaporated to obtain intermediate 2.

[0079] S3: 8.63 g of intermediate 2 was added to 21 mL of ethanol, and then 10.5 mL of 1 mol / L hydrochloric acid was slowly added, and the mixture was stirred at room temperature for 36 h, and then rotary evaporated and purified to obtain intermediate 3; 19 g of intermediate 3, 11.9 g of 4,4'-difluorobenzophenone, 15 g of potassium carbonate, 69 mL of toluene and 210 mL of N-methylpyrrolidone were added to a container, heated and stirred at 145°C for 2 h, and then the temperature was raised to 180°C for 6 h. After the reaction was completed, the mixture was added to distilled water, filtered, vacuum dried, dissolved, precipitated, washed, and vacuum dried to obtain an outer sheath material.

[0080] See also Figure 1 As shown, this embodiment discloses a method for processing a temperature-resistant and high-pressure-resistant distributed optical cable for logging, comprising the following steps:

[0081] Step 1: Wipe the surface of the optical fiber core 1 with anhydrous ethanol, evenly apply the high temperature resistant coating 2 material on the surface of the optical fiber core, solidify, twist, and then insert the twisted optical fiber core 1 containing the high temperature resistant coating 2 into the reinforcement layer 3, fill with water-blocking yarn, and seal and weld;

[0082] Step 2: Evenly wind the aramid fiber on the surface of the reinforcement layer 3, then coat it with epoxy resin glue and solidify it to obtain a hardness enhancement layer 4, which is then wound with stainless steel wire and annealed to obtain a metal armor layer 5. The outer sheath 6 material is melted, extruded, and fixed on the outer layer of the metal armor layer 5 to obtain a temperature-resistant and high-pressure resistant distributed optical cable for well logging.

[0083] Comparative Example 1: Compared with Example 1, in the process of preparing the high-temperature resistant coating material in Comparative Example 1, phthalic anhydride is not added, and other conditions remain unchanged.

[0084] Comparative Example 2: Compared with Example 1, in Comparative Example 2, no diphenyl chlorophosphate is added during the preparation of the outer sheath material, and other conditions remain unchanged.

[0085] Experimental Example: The performance of the heat-resistant and high-pressure-resistant distributed optical cables for logging prepared in Examples 2-5 and Comparative Examples 1-2 was tested. The mechanical properties of the samples were tested according to GB / T 7424.2-2008, the temperature resistance of the samples was tested according to GB / T2951.14-2008, and the combustion performance of the samples was tested according to GB / T 2406.2-2009. The test results are shown in Table 1:

[0086] Table 1

[0087] project Flattening force / (N / 100mm) Tensile strength reduction rate / % Oxygen index / % Example 2 2545 5.67 36.3 Example 3 2537 5.81 36.1 Example 4 2521 5.98 36.2 Example 5 2498 5.84 35.8 Comparative Example 1 1894 8.15 35.9 Comparative Example 2 1913 8.02 28.8

[0088] From the test results in Table 1, it can be seen that the distributed optical cables for well logging prepared in Examples 2-5 of the present invention have excellent high-voltage resistance, temperature resistance and flame retardancy. From the comparison between Comparative Example 1 and Examples 2-5, it can be seen that the addition of phthalic anhydride can effectively improve the high-voltage resistance and high-temperature resistance of the distributed optical cables for well logging; from the comparison between Comparative Example 2 and Examples 2-5, it can be seen that the addition of 4,4'-difluorobenzophenone can effectively improve the high-voltage resistance, high-temperature resistance and flame retardancy of the distributed optical cables for well logging.

[0089] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0090] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A temperature-resistant and high-pressure-resistant distributed optical cable for logging, characterized in that: It includes an optical fiber core, a high-temperature resistant coating, a reinforcement layer, a hardness enhancement layer, a metal armor layer and an outer sheath which are arranged in sequence from the inside to the outside. There are multiple optical fiber cores, and the outer periphery of the optical fiber core is evenly coated with a high-temperature resistant coating. The optical fiber cores are twisted and connected to each other and wrapped with a reinforcement layer on the outside. A hardness enhancement layer is wrapped on the outside of the reinforcement layer, a metal armor layer is wrapped on the outside of the hardness enhancement layer, and an outer sheath is wrapped on the outside of the metal armor layer.

2. The temperature-resistant and high-pressure-resistant distributed optical cable for logging according to claim 1, characterized in that: The method for preparing the high temperature resistant coating material comprises the following steps: Q1: 2-amino-3-hydroxymethylpyridine and polyoxymethylene are added to N,N-dimethylformamide and mixed, heated and stirred, and then heated to react. After the reaction is completed, the product is added to distilled water, and solids are precipitated. The solids are filtered and dried to obtain an intermediate monomer. The intermediate monomer and phthalic anhydride are added to a container containing N,N-dimethylformamide, and then triethylamine is added. The reaction is carried out under a nitrogen atmosphere to obtain a monomer. Q2: Add 2-aminodiphenylamine and sodium hydride to N,N-dimethylformamide, stir at room temperature, then add 4-fluoronitrobenzene, continue to stir at room temperature to react, after the reaction is completed, add to distilled water to quench the reaction, there is precipitation, suction filtration, dissolution, washing, drying, filtering, concentration, vacuum drying to obtain a crude product; add the crude product to ethanol to dissolve, then add palladium / carbon and hydrazine hydrate, heat and stir to react, after the reaction is completed, cool, dilute, filter, wash, separate, dry the organic phase, filter, concentrate, vacuum dry, purify to obtain a solid; Q3: Add the monomer and solid matter into N,N-dimethylformamide in sequence, heat and stir to react, and after the reaction is completed, filter, wash, purify and dry to obtain a high temperature resistant coating material.

3. The temperature-resistant and high-pressure-resistant distributed optical cable for logging according to claim 2, characterized in that: In the Q1, the dosage ratio of 2-amino-3-hydroxymethylpyridine, polyoxymethylene, N,N-dimethylformamide and distilled water is (1.5-1.8) g: (0.9-1.2) g: (20-24) mL: (200-230) mL, the heating and stirring temperature is 100-120° C., the stirring time is 2-3 h, the heating reaction temperature is 140-150° C., and the reaction time is 7-9 h; the dosage ratio of the intermediate monomer, phthalic anhydride, N,N-dimethylformamide and triethylamine is (2.13-2.35) g: (1.85-2.02) g: (10-20) mL: (0.2-0.25) g, and the reaction time is 20-24 h.

4. The temperature-resistant and high-pressure-resistant distributed optical cable for logging according to claim 2, characterized in that: In Q2, the amount ratio of 2-aminodiphenylamine, sodium hydride, N,N-dimethylformamide and 4-fluoronitrobenzene is (3.22-3.56) g: (1.05-1.38) g: (32-46) mL: (3.18-3.59) g, the stirring time at room temperature is 1-2 h, the stirring reaction time at room temperature is continued for 5-7 h, the mixture is dissolved with dichloromethane, washed with saturated sodium chloride solution, and dried with anhydrous sodium sulfate; the amount ratio of crude product, ethanol, palladium / carbon and hydrazine hydrate is (2.12-2.46) g: (40-60) mL: (1.12-1.54) g: (5.89-6.16) mL, the heating and stirring reaction temperature is 80-85°C, the reaction time is 4-6 h, the mixture is diluted with dichloromethane, washed with saturated sodium chloride solution, and the organic phase is dried with anhydrous sodium sulfate.

5. The temperature-resistant and high-pressure-resistant distributed optical cable for logging according to claim 2, characterized in that: In the Q3, the usage ratio of the monomer, the solid and N,N-dimethylformamide is (2.04-2.65) g: (2.43-2.96) g: (10-15) mL, the heating temperature is 110-140° C., and the reaction time is 8-10 h.

6. The temperature-resistant and high-pressure-resistant distributed optical cable for logging according to claim 1, characterized in that: The method for preparing the outer sheath material comprises the following steps: S1: Add dopamine hydrochloride and imidazole to a container filled with dichloromethane, stir magnetically, then dropwise add triethylsilyl chloride, stir at room temperature for reaction, and after the reaction is completed, dilute, extract, wash, dry, and rotary evaporate to obtain intermediate 1; S2: adding intermediate 1 and triethylamine to a container filled with tetrahydrofuran, then dissolving diphenyl chlorophosphate in tetrahydrofuran and slowly adding the mixture dropwise to the container, stirring the mixture magnetically to react, and after the reaction is completed, blowing off, diluting, extracting, washing, drying, and rotary evaporation are performed to obtain intermediate 2; S3: Add intermediate 2 to ethanol, then slowly add hydrochloric acid, stir at room temperature, rotary evaporate, and purify to obtain intermediate 3; add intermediate 3, 4,4'-difluorobenzophenone, potassium carbonate, toluene and N-methylpyrrolidone to a container, heat and stir under reflux, continue to heat and react, after the reaction is completed, add to distilled water, filter, vacuum dry, dissolve, precipitate, wash, and vacuum dry to obtain an outer sheath material.

7. The temperature-resistant and high-pressure-resistant distributed optical cable for logging according to claim 6, characterized in that: In the S1, the dosage ratio of dopamine hydrochloride, imidazole, dichloromethane and triethylsilyl chloride is (3.2-4.6) g: (5.12-5.98) g: (60-80) mL: (7.63-8.02) g, the stirring reaction time is 12-16 h, diluted with dichloromethane, extracted and washed with 1 mol / L sodium bicarbonate aqueous solution, deionized water and saturated sodium chloride solution, and dried with anhydrous sodium sulfate.

8. The temperature-resistant and high-pressure-resistant distributed optical cable for logging according to claim 6, characterized in that: In S2, the usage ratio of intermediate 1, triethylamine and diphenyl chlorophosphate is (7.1-8.6) g: (2.8-3.6) g: (5.12-5.98) g, the magnetic stirring reaction time is 12-16 h, ethyl acetate is added for dilution, 1 mol / L ammonium chloride solution and saturated sodium chloride solution are used for extraction and washing, and the mixture is dried with anhydrous sodium sulfate.

9. The temperature-resistant and high-pressure-resistant distributed optical cable for logging according to claim 6, characterized in that: In S3, the amount ratio of intermediate 2, ethanol and hydrochloric acid is (8.12-9.35) g: (20-25) mL: (10-12) mL, the concentration of hydrochloric acid is 1 mol / L, and the stirring time at room temperature is 24-36 h; the amount ratio of intermediate 3, 4,4'-difluorobenzophenone, potassium carbonate, toluene and N-methylpyrrolidone is (18-22) g: (11.8-13.6) g: (13-19) g: (68-76) mL: (200-230) mL, the heating stirring reflux temperature is 140-150° C., the reflux time is 1-2 h, the heating reaction temperature is 170-190° C., and the reaction time is 4-6 h.

10. The method for processing the temperature-resistant and high-pressure-resistant distributed optical cable for logging according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1: Wipe the surface of the optical fiber core with anhydrous ethanol, evenly apply the high-temperature resistant coating on the surface of the optical fiber core, solidify, twist, and then insert the twisted optical fiber core containing the high-temperature resistant coating into the reinforcement layer, fill with water-blocking yarn, and seal and weld; Step 2: Evenly wind the aramid fiber on the surface of the stainless steel tube, then coat it with epoxy resin glue and solidify it to obtain a hardness enhancement layer, then wind it with stainless steel wire, and obtain a metal armor layer after annealing. Melt the outer sheath material, extrude it, and fix it on the outer layer of the metal armor layer to obtain a temperature-resistant and high-pressure resistant distributed optical cable for well logging.

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