High-temperature-resistant and high-wear-resistant pipe and preparation method thereof

Abstract

The application belongs to the technical field of pipe materials, and relates to a high-temperature-resistant and high-wear-resistant pipe and a preparation method thereof. The high-temperature-resistant and high-wear-resistant pipe is a composite pipe with double-layer materials, which is composed of a POK inner pipe as an inner layer and a PE outer pipe as an outer layer. The POK inner pipe as the inner layer is obtained by extruding and shaping POK material after melt blending of POK resin, toughening agent, ABS cooling agent, antioxidant and lubricant at a temperature range of 200-240 DEG C. The PE outer pipe as the outer layer is obtained by extruding and shaping PE material after melt blending of PE resin, antioxidant and lubricant at a temperature range of 170-210 DEG C. The PE pipe as the outer layer tightly wraps the POK pipe as the inner layer, and the POK inner pipe as the inner layer and the PE outer pipe as the outer layer are tightly attached. Compared with the prior art, the application has the advantages of excellent high-temperature-resistant and high-wear-resistant performance, anti-aging performance and high-impact resistance, and low production cost.

Description

Technical Field

[0001] This invention belongs to the field of pipeline material technology, and in particular relates to a high-temperature resistant and high-wear-resistant pipe and its preparation method. Background Technology

[0002] POK is a highly crystalline polymer obtained by copolymerizing carbon monoxide-containing olefins (ethylene, propylene) in the air. It possesses high strength, high temperature resistance, high wear resistance, and resistance to moderate acids and alkalis. POK material has a density of 1.1-1.3 g / cm³. 3 With a Vicat softening temperature of 200℃ (B50 method), POK exhibits excellent temperature resistance and is widely used in the petrochemical industry. In addition, it also has high wear resistance, high strength, and good corrosion resistance. However, the high price of POK raw materials greatly limits its application.

[0003] Ultra-high molecular weight polyethylene (UHMW-PE) is a linear thermoplastic engineering plastic with excellent comprehensive properties, including wear resistance, impact resistance, aging resistance, and long service life. It is currently widely used in the fiber, rope, helmet, and oil extraction industries. However, due to its Vicat softening temperature of only about 120°C, its application in oil pipelines in the oil extraction industry is currently limited to depths of up to 3000 meters. Furthermore, compared to POK (polyoxyethylene), UHMW-PE is priced at only half the cost.

[0004] Therefore, there is a lack of materials in the existing technology that simultaneously possess excellent high temperature resistance, wear resistance, aging resistance, and high impact resistance, while also having low production costs. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the prior art and provide a high-temperature resistant and high-wear-resistant pipe and its preparation method.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] This invention first provides a high-temperature resistant and high-wear-resistant pipe, which is a composite pipe composed of a double-layer material consisting of an inner POK inner pipe and an outer PE outer pipe.

[0008] The inner POK tube is a POK material obtained by extruding and shaping through a mold after POK resin, toughening agent, ABS cooling agent, antioxidant and lubricant are melted and blended in the temperature range of 200-240℃.

[0009] The outer PE pipe is a PE pipe obtained by extruding and shaping PE material after PE resin, antioxidant and lubricant are melted and blended in the temperature range of 170-210℃.

[0010] The outer PE pipe tightly wraps the inner POK pipe, and the inner POK pipe and the outer PE pipe are closely fitted together.

[0011] In one embodiment of the present invention, the material used for the inner POK inner tube mainly comprises, by weight:

[0012] POK resin: 60-97 parts;

[0013] ABS cooling agent: 5-10 parts;

[0014] POK toughening agent: 10-20 parts

[0015] Antioxidant: 0-1.2 parts

[0016] Lubricant: 0-2 parts.

[0017] In one embodiment of the present invention, the POK resin is one or more POK resins with a number average molecular weight between 40,000 and 120,000 and a melt index of 3-8 g / 10 min at 240°C / 2.16 kg. Preferably, the selected POK resin has a number average molecular weight of 60,000 and a melt index of 3 g / 10 min.

[0018] In one embodiment of the present invention, the ABS cooling agent is selected from one or more combinations of high polyester polymer, high crystallinity peroxide, polymeric initiator, styrene-acrylonitrile copolymer or ethylene bis-stearamide, preferably a low viscosity styrene-acrylonitrile copolymer.

[0019] In one embodiment of the present invention, the POK toughening agent is selected from one or more of methyl methacrylate-butadiene-styrene copolymer, maleic anhydride-grafted ethylene-vinyl acetate copolymer, or maleic anhydride-grafted polycarbonate.

[0020] In one embodiment of the present invention, the material used for the outer PE outer tube, by weight, mainly comprises:

[0021] PE resin: 60-97 parts;

[0022] PE toughening agent: 10-15 parts

[0023] Antioxidant: 0-1.2 parts

[0024] Lubricant: 0-2 parts.

[0025] In one embodiment of the present invention, the PE resin is selected from one or more combinations of ultra-high molecular weight polyethylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene or linear low-density polyethylene, preferably, purchased molecular weight polyethylene.

[0026] In one embodiment of the present invention, the PE toughening agent is selected from one or more combinations of SBS, SEBS, TPE or POE, preferably, the selected toughening agent is POE.

[0027] In one embodiment of the present invention, the antioxidant is selected from one or a combination of antioxidant 2450, antioxidant 1076, antioxidant 1010 and antioxidant 168. Preferably, the selected antioxidant is antioxidant 1010 and antioxidant 168.

[0028] In one embodiment of the present invention, the lubricant is selected from at least one or a combination of zinc stearate, calcium stearate, butyl stearate, oleamide, pentaerythritol stearate or ethylene bis-stearamide.

[0029] The present invention further provides a method for preparing the high-temperature resistant and high-wear-resistant pipe, comprising the following steps:

[0030] POK resin, toughening agent, ABS cooling agent, antioxidant and lubricant are melt-blended in a temperature range of 200-240℃ to obtain POK material that can be stably extruded;

[0031] PE resin, antioxidant and lubricant are melt-blended in a temperature range of 170-210℃ to obtain PE material that can be stably extruded.

[0032] After POK and PE materials are extruded simultaneously and stably, they are compounded through extrusion molding dies. The POK material is extruded to form the POK inner tube, and the PE material is extruded to form the PE outer tube. The POK inner tube and the PE outer tube are tightly bonded and extruded together to form a composite tube with two layers of materials.

[0033] Because the shrinkage rate of POK during extrusion is less than that of PE, the PE pipe, as the outer layer, can tightly wrap the inner POK pipe, achieving a tight fit.

[0034] In one embodiment of the present invention, when preparing the POK inner tube, the processing equipment selected for melting the mixture is selected from a mixer, a single-screw extruder, a twin-screw extruder, or an open mill. Preferably, a single-screw extruder is selected, with a processing temperature range of 200-240°C and a main engine speed of 200-600 rpm.

[0035] In one embodiment of the present invention, when preparing the PE outer pipe, the processing equipment selected for melting the mixture is selected from a mixer, a single-screw extruder, a twin-screw extruder, or an open mill. Preferably, a single-screw extruder is selected, with a processing temperature range of 170-210°C and a main machine speed of 200-600 rpm.

[0036] In this invention, the POK inner tube and the PE outer tube are extruded simultaneously and then composited through an extrusion molding die. The POK inner tube and the PE outer tube are tightly bonded and extruded together to form a composite tube with two layers of material.

[0037] In one embodiment of the present invention, the extrusion molding die includes a core and a die. A POK material channel for extruding and molding a POK inner tube is formed in the core, and a PE material channel for extruding and molding a PE outer tube is formed in the die. The PE material channel is located outside the POK material channel, and the PE outer tube extruded and molded by the PE material channel can tightly wrap the POK inner tube extruded and molded by the POK material channel, thus achieving a tight fit.

[0038] In one embodiment of the present invention, the die of the extrusion molding die is equipped with a high-temperature resistant polytetrafluoroethylene annular die, which can reduce the smoothness of the outer layer material.

[0039] In one embodiment of the present invention, the dimensions of the POK material channel and the PE material channel are adjustable to allow the thickness of the inner and outer layer materials to be adjusted according to actual conditions.

[0040] In one embodiment of the present invention, the die core has a tetrafluoroethylene coating to ensure that the inner POK material can be extruded smoothly, reduce the residence time of the POK material in the extrusion equipment, reduce the generation of coke, and inhibit the over-processing and carbonization of the POK material.

[0041] In one embodiment of the present invention, after the composite pipe is extruded through an extrusion molding die, it is cooled and shaped by a vacuum spray water tank. At the same time, the shrinkage difference between the extrusion shrinkage rate of the outer PE layer and the extrusion shrinkage rate of POK layer is utilized to achieve a tight bond between the two materials, thereby achieving the extrusion of different materials in the inner and outer layers under load.

[0042] This invention relates to a special high-temperature resistant and wear-resistant pipe made by simultaneously extruding polyketone (POK) as the main raw material with other functional components and polyethylene resin as the base resin with other functional components, and then using an extrusion die to produce a special high-temperature resistant and wear-resistant pipe with an inner layer of polyketone and an outer layer of polyethylene. The inner polyketone (POK) material itself has high temperature resistance, high wear resistance, and corrosion resistance, which can meet the transportation requirements of high-temperature or high-temperature corrosive media. At the same time, the outer polyethylene (PE) material has excellent aging resistance and low-temperature impact resistance, which can ensure the outdoor working conditions of the internally transported media.

[0043] The main principle of the high-temperature and high-wear-resistant pipe of this invention is as follows: a layer of PE pipe is laminated to the outer layer of POK pipe, so that the inner layer of the pipe has excellent temperature and wear resistance, while the outer layer has excellent impact resistance and aging resistance. At the same time, the commercial price of PE material is only half that of POK. The introduction of PE material realizes the low-cost application of POK material and also realizes the application of PE material in deep wells below 3000 meters. It is of great significance for reducing the cost of deep well oil and gas extraction pipelines and the widespread application of POK material.

[0044] The high-temperature and high-wear-resistant pipe of this invention serves as a substitute for pipes used in special industries under high-temperature and highly corrosive conditions. Compared with several pipe materials currently used most extensively in oil and gas extraction and transportation pipelines, it has the following advantages:

[0045] Compared to ultra-high molecular weight polyethylene pipes, the temperature resistance of the pipes can be increased from 70℃ to 185℃, and the compressive strength is increased by 3 times and the tensile strength is increased by 2 times. Compared to nylon pipes, it has better resistance to hydrolysis, chemical corrosion, fuel, and high temperature, as well as a more balanced rigidity and toughness. Compared to steel pipes, it has the advantages of being lighter, having higher media barrier properties, and lower cost.

[0046] Meanwhile, the production process of this invention does not involve excessive, complex, or highly precise instruments. Through extrusion molding and the utilization of material properties, POK and PE materials are compositely extruded, resulting in a composite pipe with excellent performance after molding. This technology has scalability and excellent applicability, and its future technological output has significant practical implications for solving problems faced by the petroleum industry. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the extrusion molding die. Detailed Implementation

[0048] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0049] Unless otherwise specified in the following examples and comparative examples, the manufacturer's general instructions shall be followed.

[0050] The POK resin used in this embodiment of the invention is POK-M630A manufactured by Hyosung in South Korea.

[0051] The PE resin used in this embodiment of the invention is PE-UHMW, manufactured by Yanshan Petrochemical.

[0052] The POK cooling agent used in this embodiment of the invention is styrene-acrylonitrile copolymer (SAN), specifically the brand name Chimei PN-127H.

[0053] The POK toughening agent used in the embodiments of the present invention is methyl methacrylate-butadiene-styrene copolymer (MBS), specifically Dow EXL-2620.

[0054] The PE toughening agent used in the embodiments of the present invention is POE-7467 Dow.

[0055] The antioxidants used in the embodiments of the present invention are antioxidant 1010 and antioxidant 168 used in combination.

[0056] The preparation methods of the inner POK pipe and the outer PE pipe in the embodiments of the present invention mainly include several steps such as blending, melting, extrusion, compounding and vacuum shaping. The extrusion of both POK pipe and PE pipe adopts single screw extrusion.

[0057] The processing temperature range for the single-screw extruder used in POK pipe processing is 200-240℃, and the specific temperature settings are shown in Table 1.

[0058] Table 1 Processing Temperature of Inner Layer POK Pipe

[0059]

[0060] The processing temperature range for single-screw extruders in PE pipe manufacturing is 170-210℃, and the specific temperature settings are shown in Table 2.

[0061] Table 2 Processing Temperature of Outer PE Pipe Material

[0062]

[0063] In the following embodiments, the extrusion molding die is as follows: Figure 1 As shown, it includes a core mold 1 and a die 2. The core mold 1 has a POK material channel 3 for extruding and molding a POK inner tube, and the die 2 has a PE material channel 4 for extruding and molding a PE outer tube. The PE material channel 4 is located outside the POK material channel 3, and the PE outer tube extruded by the PE material channel 4 can tightly wrap the POK inner tube extruded by the POK material channel 3, thus achieving a tight fit.

[0064] The extrusion die 2 is equipped with a high-temperature resistant polytetrafluoroethylene (PTFE) annular die 5, which can reduce the smoothness of the outer layer material. The dimensions of the POK material channel 3 and the PE material channel 4 are adjustable to accommodate adjustments in the thickness of the inner and outer layers as needed. The die core 1 has a PTFE coating to ensure smooth extrusion of the inner POK material, reduce the residence time of the POK material in the extrusion equipment, minimize coking, and inhibit over-processing and carbonization of the POK material.

[0065] After the composite pipe is extruded through the extrusion molding die, it is cooled and shaped by a vacuum spray water tank. At the same time, the shrinkage difference between the outer PE layer and the POK layer is utilized to achieve a tight bond between the two materials, thus realizing the extrusion of different materials in the inner and outer layers under load.

[0066] In this embodiment of the invention, the pipe material produced has a specification of 2. 7 / 8 specification inner-lined oil pipe, specific dimensions are outer diameter With a wall thickness of 3.5mm, the composite pipe was subjected to hydrostatic pressure, drop hammer impact (-20℃), Vicat softening temperature and tensile strength tests.

[0067] Example 1

[0068] After drying POK resin, styrene-acrylonitrile copolymer (SAN), and methyl methacrylate-butadiene-styrene copolymer (MBS) in a vacuum oven at 70°C for 24 hours, the above three materials, antioxidant 1010, antioxidant 168, and butyl stearate were mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of POK:SAN:MBS:antioxidant 1010-168:butyl stearate = 100:5:10:0.6:0.2. After being mixed evenly, the mixture was added to a single-screw extruder, and the screw speed was gradually increased to start extruding the POK material.

[0069] PE resin, POE, antioxidant 1010 and antioxidant 168, and stearic acid are mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of PE:POE:antioxidant 1010-168:stearic acid = 100:5:0.6:0.2. After the mixture is evenly mixed, it is added to a single-screw extruder, and the single screw speed is gradually increased to start the PE material extrusion.

[0070] After the inner layer of POK material and the outer layer of PE material are gradually extruded and stabilized, the composite pipe material extruded from the extrusion die clearly shows that POK (light yellow) and PE (white) are neither mixed with each other and are tightly bonded. The POK material extruder speed is controlled at 396 rpm, and the PE material extruder speed is controlled at 215 rpm. The materials are then pulled into a vacuum forming box for shaping the composite pipe. The vacuum forming box uses spray cooling, and the vacuum pressure is -0.6 MPa.

[0071] Example 2

[0072] After drying POK resin, styrene-acrylonitrile copolymer (SAN), and methyl methacrylate-butadiene-styrene copolymer (MBS) in a vacuum oven at 70°C for 24 hours, the above three materials, antioxidant 1010, antioxidant 168, and butyl stearate were mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of POK:SAN:MBS:antioxidant 1010-168:butyl stearate = 100:5:10:0.6:0.2. After being mixed evenly, the mixture was added to a single-screw extruder, and the screw speed was gradually increased to start extruding the POK material.

[0073] PE resin, POE, antioxidant 1010 and antioxidant 168, and stearic acid are mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of PE:POE:antioxidant 1010-168:stearic acid = 100:5:0.6:0.2. After the mixture is evenly mixed, it is added to a single-screw extruder, and the single screw speed is gradually increased to start the PE material extrusion.

[0074] After the inner layer of POK material and the outer layer of PE material are gradually extruded and stabilized, the composite pipe material extruded from the extrusion die clearly shows that POK (light yellow) and PE (white) are neither mixed with each other and are tightly bonded. The POK material extruder speed is controlled at 510 rpm, and the PE material extruder speed is controlled at 103 rpm. The materials are then pulled into a vacuum forming box for shaping the composite pipe. The vacuum forming box uses spray cooling, and the vacuum pressure is -0.6 MPa.

[0075] Example 3

[0076] After drying POK resin, styrene-acrylonitrile copolymer (SAN), and methyl methacrylate-butadiene-styrene copolymer (MBS) in a vacuum oven at 70°C for 24 hours, the above three materials, antioxidant 1010, antioxidant 168, and butyl stearate were mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of POK:SAN:MBS:antioxidant 1010-168:butyl stearate = 100:5:8:0.6:0.2. After being mixed evenly, the mixture was added to a single-screw extruder, and the screw speed was gradually increased to start extruding the POK material.

[0077] PE resin, POE, antioxidant 1010 and antioxidant 168, and stearic acid are mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of PE:POE:antioxidant 1010-168:stearic acid = 100:5:0.6:0.2. After the mixture is evenly mixed, it is added to a single-screw extruder, and the single screw speed is gradually increased to start the PE material extrusion.

[0078] After the inner layer of POK material and the outer layer of PE material are gradually extruded and stabilized, the composite pipe material extruded from the extrusion die clearly shows that POK (light yellow) and PE (white) are neither mixed with each other and are tightly bonded. The POK material extruder speed is controlled at 396 rpm, and the PE material extruder speed is controlled at 215 rpm. The materials are then pulled into a vacuum forming box for shaping the composite pipe. The vacuum forming box uses spray cooling, and the vacuum pressure is -0.6 MPa.

[0079] Example 4

[0080] After drying POK resin, styrene-acrylonitrile copolymer (SAN), and methyl methacrylate-butadiene-styrene copolymer (MBS) in a vacuum oven at 70°C for 24 hours, the above three materials, antioxidant 1010, antioxidant 168, and butyl stearate were mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of POK:SAN:MBS:antioxidant 1010-168:butyl stearate = 100:7:10:0.6:0.2. After being mixed evenly, the mixture was added to a single-screw extruder, and the screw speed was gradually increased to start extruding the POK material.

[0081] PE resin, POE, antioxidant 1010 and antioxidant 168, and stearic acid are mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of PE:POE:antioxidant 1010-168:stearic acid = 100:5:0.6:0.2. After the mixture is evenly mixed, it is added to a single-screw extruder, and the single screw speed is gradually increased to start the PE material extrusion.

[0082] After the inner layer of POK material and the outer layer of PE material are gradually extruded and stabilized, the composite pipe material extruded from the extrusion die clearly shows that POK (light yellow) and PE (white) are neither mixed with each other and are tightly bonded. The POK material extruder speed is controlled at 510 rpm, and the PE material extruder speed is controlled at 103 rpm. The materials are then pulled into a vacuum forming box for shaping the composite pipe. The vacuum forming box uses spray cooling, and the vacuum pressure is -0.6 MPa.

[0083] Comparative Example 1

[0084] After drying POK resin, styrene-acrylonitrile copolymer (SAN), and methyl methacrylate-butadiene-styrene copolymer (MBS) in a vacuum oven at 70°C for 24 hours, the above three materials, antioxidant 1010, antioxidant 168, and butyl stearate were mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of POK:SAN:MBS:antioxidant 1010-168:butyl stearate = 100:5:10:0.6:0.2. After being mixed evenly, the mixture was added to a single-screw extruder, and the screw speed was gradually increased to start extruding the POK material.

[0085] PE resin, POE, antioxidant 1010 and antioxidant 168, and stearic acid are mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of PE:POE:antioxidant 1010-168:stearic acid = 100:5:0.6:0.2. After the mixture is evenly mixed, it is added to a single-screw extruder, and the single screw speed is gradually increased to start the PE material extrusion.

[0086] After the inner layer of POK material and the outer layer of PE material are gradually extruded and stabilized, the composite pipe material extruded from the extrusion die clearly shows that POK (light yellow) and PE (white) are neither mixed with each other and are tightly bonded. The POK material extruder speed is controlled at 597 rpm, and the PE material extruder speed is controlled at 0 rpm. The materials are then pulled into a vacuum forming box for shaping the composite pipe. The vacuum forming box uses spray cooling, and the vacuum pressure is -0.6 MPa.

[0087] Comparative Example 2

[0088] After drying POK resin, styrene-acrylonitrile copolymer (SAN), and methyl methacrylate-butadiene-styrene copolymer (MBS) in a vacuum oven at 70°C for 24 hours, the above three materials, antioxidant 1010, antioxidant 168, and butyl stearate were mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of POK:SAN:MBS:antioxidant 1010-168:butyl stearate = 100:5:0:0.6:0.2. After being mixed evenly, the mixture was added to a single-screw extruder, and the screw speed was gradually increased to start extruding the POK material.

[0089] PE resin, POE, antioxidant 1010 and antioxidant 168, and stearic acid are mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of PE:POE:antioxidant 1010-168:stearic acid = 100:5:0.6:0.2. After the mixture is evenly mixed, it is added to a single-screw extruder, and the single screw speed is gradually increased to start the PE material extrusion.

[0090] After the inner layer of POK material and the outer layer of PE material are gradually extruded and stabilized, the composite pipe material extruded from the extrusion die clearly shows that POK (light yellow) and PE (white) are neither mixed with each other and are tightly bonded. The POK material extruder speed is controlled at 510 rpm, and the PE material extruder speed is controlled at 103 rpm. The materials are then pulled into a vacuum forming box for shaping the composite pipe. The vacuum forming box uses spray cooling, and the vacuum pressure is -0.6 MPa.

[0091] Comparative Example 3

[0092] After drying POK resin, styrene-acrylonitrile copolymer (SAN), and methyl methacrylate-butadiene-styrene copolymer (MBS) in a vacuum oven at 70°C for 24 hours, the above three materials, antioxidant 1010, antioxidant 168, and butyl stearate were mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of POK:SAN:MBS:antioxidant 1010-168:butyl stearate = 100:0:10:0.6:0.2. After being mixed evenly, the mixture was fed into a single-screw extruder, and the screw speed was gradually increased to start extruding the POK material.

[0093] PE resin, POE, antioxidant 1010 and antioxidant 168, and stearic acid are mixed in a mixing pot at room temperature for 20 minutes according to the mass ratio of PE:POE:antioxidant 1010-168:stearic acid = 100:5:0.6:0.2. After the mixture is evenly mixed, it is added to a single-screw extruder, and the single screw speed is gradually increased to start the PE material extrusion.

[0094] After the inner layer of POK material and the outer layer of PE material are gradually extruded and stabilized, the composite pipe material extruded from the extrusion die clearly shows that POK (light yellow) and PE (white) are neither mixed with each other and are tightly bonded. The POK material extruder speed is controlled at 396 rpm, and the PE material extruder speed is controlled at 215 rpm. The materials are then pulled into a vacuum forming box for shaping the composite pipe. The vacuum forming box uses spray cooling, and the vacuum pressure is -0.6 MPa.

[0095] The performance of the pipes obtained in the examples and comparative examples is shown in Table 3.

[0096] Table 3. Pipe performance obtained from the examples and comparative examples.

[0097]

[0098] As can be seen from the alloy properties shown in Table 3,

[0099] ① Examples 1-4 and Comparative Example 1 show that the outer PE pipe can effectively protect the inner POK pipe, ensuring the impact resistance of the composite pipe at -20℃.

[0100] ② Examples 1-4 and Comparative Example 2 show that when the outer PE pipe wall is thin, the MBS toughening agent added to the inner POK material can effectively improve the impact resistance of the inner POK pipe.

[0101] ③ Examples 1-4 and Comparative Example 3 show that the SAN cooling agent added to the inner POK material can effectively ensure the stable extrusion of POK, reduce the amount of coke generated by screw friction in the POK material entering the pipe, and avoid the occurrence of weak points on the pipe.

[0102] ④ All examples and comparative examples demonstrate that adding SAN cooling agent and toughening agent MBS to POK will reduce the Vicat softening temperature and tensile strength of the inner POK material, and the decrease will gradually increase with the increase of the amount added.

[0103] ⑤ The product in Example 2 has excellent performance in all aspects, with a Vicat softening temperature of 167.5℃, and can be used for oil and gas extraction work at a depth of about 5000 meters.

[0104] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A high-temperature resistant and high-wear-resistant pipe, characterized in that, The high-temperature resistant and high-wear-resistant pipe is a composite pipe composed of a double-layer material, consisting of an inner POK inner pipe and an outer PE outer pipe. The inner POK tube is obtained by extruding and shaping POK material after POK resin, POK toughening agent, styrene-acrylonitrile copolymer, antioxidant and lubricant are melt-blended in the temperature range of 200-240℃. The outer PE tube is obtained by extruding and shaping PE material after PE resin, PE toughening agent, antioxidant and lubricant are melt-blended in the temperature range of 170-210℃. The outer PE tube tightly wraps the inner POK tube, and the inner POK tube and the outer PE tube are closely fitted together. The materials used in the inner POK tube, by weight, mainly include: POK resin: 100 parts; Styrene-acrylonitrile copolymer: 5 parts; POK toughening agent: 10 parts; Antioxidant: 0.6 parts; Lubricant: 0.2 parts; The materials used in the outer PE outer tube, by weight, mainly include: PE resin: 100 parts; PE toughening agent: 5 parts; Antioxidant: 0.6 parts; Lubricant: 0.2 parts; The POK toughening agent is methyl methacrylate-butadiene-styrene copolymer; the PE toughening agent is POE; the antioxidant is a combination of antioxidant 1010 and antioxidant 168; and the lubricant is butyl stearate.

2. The high-temperature resistant and high-wear-resistant pipe according to claim 1, characterized in that, The POK resin is one or more POK resins with a number average molecular weight range of 40,000-120,000 and a melt index of 3-8 g / 10 min at 240℃ / 2.16 kg.

3. The method for preparing the high-temperature resistant and high-wear-resistant pipe according to claim 1, characterized in that, Includes the following steps: POK resin, POK toughening agent, styrene-acrylonitrile copolymer, antioxidant and lubricant are melt-blended in a temperature range of 200-240℃ to obtain POK material that can be stably extruded. PE resin, PE toughening agent, antioxidant and lubricant are melt-blended in a temperature range of 170-210℃ to obtain PE material that can be stably extruded. After POK and PE materials are extruded simultaneously and stably, they are compounded through extrusion molding dies. The POK material is extruded to form the POK inner tube, and the PE material is extruded to form the PE outer tube. The POK inner tube and the PE outer tube are tightly bonded and extruded together to form a composite tube with two layers of materials.

4. The preparation method according to claim 3, characterized in that, When preparing the POK inner tube, the processing equipment for melting the mixture is a mixer, a single-screw extruder, a twin-screw extruder, or an open mill. When using a single-screw extruder, the processing temperature range of the single-screw extruder is 200-240℃, and the main engine speed is 200-600rpm. When preparing PE outer pipes, the processing equipment for melting the mixture is a mixer, a single-screw extruder, a twin-screw extruder, or an open mill. When using a single-screw extruder, the processing temperature range of the single-screw extruder is 170-210℃, and the main machine speed is 200-600rpm.

5. The preparation method according to claim 3, characterized in that, The extrusion molding die includes a core (1) and a die (2). The core (1) has a POK material channel (3) for extruding and molding a POK inner tube, and the die (2) has a PE material channel (4) for extruding and molding a PE outer tube. The PE material channel (4) is located outside the POK material channel (3), and the PE outer tube extruded by the PE material channel (4) can tightly wrap the POK inner tube extruded by the POK material channel (3) to achieve a tight fit.

6. The preparation method according to claim 5, characterized in that, The die (2) of the extrusion molding die is equipped with a high-temperature resistant polytetrafluoroethylene ring die (5).

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