Production process of a thin-walled reducer

Abstract

The present invention discloses a production process of a thin-walled reducing pipe. After heating, piercing, tube rolling, and sizing treatment of a tube blank, a sized pipe is obtained; then, after quenching, hot expansion, and tempering treatment of the sized pipe, it is cooled to room temperature, and a wear-resistant and corrosion-resistant coating is sprayed on the pipe wall surface, followed by heat preservation treatment to obtain the pipe. The wear-resistant and corrosion-resistant coating comprises the following raw materials in parts by weight: 60-80 parts of an enhanced resin emulsion, 15-20 parts of enhanced particles, 8-10 parts of aluminum tripolyphosphate, 2-3 parts of SN-154 defoamer, 1.5-2 parts of DH-3170 leveling agent, and 1-1.5 parts of sodium dodecylbenzenesulfonate. The enhanced particles are based on graphene and silicon carbide, and the compound use with the enhanced resin further improves the wear resistance of the coating. At the same time, the surface of the enhanced particles is wrapped by a hyperbranched polymer, which can be quickly and evenly dispersed in the coating, and at the same time enhances the corrosion resistance of the reducing pipe and improves the service life of the reducing pipe.

Description

Technical Field

[0001] The present invention relates to the technical field of reducing pipe preparation, and particularly relates to a production process for thin-walled reducing pipes. Background Art

[0002] A reducing pipe, also known as a reducer, is a pipe fitting with different diameters at both straight ends, mainly used for connecting two different pipe diameters. Reducing pipes can be divided into circular reducing pipes, rectangular reducing pipes, U-shaped reducing pipes, and rectangular connecting pipes with a torsional direction. Among them, circular reducing pipes are the most widely used. The main materials of reducing pipes include stainless steel reducing pipes, alloy steel reducing pipes, etc. The commonly used forming processes for reducing pipes are necking pressing, expanding pressing, or necking plus expanding pressing.

[0003] After the reducing pipe is produced, its surface will have scratches and rust spots due to bumps and oxidation during the production process. Therefore, it needs to be finely processed. The traditional fine processing of reducing pipe production and manufacturing mainly involves clamping the reducing pipe with a clamping pliers, and then manually holding a grinding machine for repair and grinding. At the same time, during use, due to the transportation of corrosive liquids and external frictional forces, the reducing pipe will be damaged, thus affecting normal use. Summary of the Invention

[0004] The purpose of the present invention is to provide a production process for thin-walled reducing pipes, which solves the problems of poor wear resistance, corrosion resistance, and low service life of thin-walled reducing pipes at the present stage.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A production process for thin-walled reducing pipes specifically includes the following steps:

[0007] Step S1: Heat the pipe blank at a temperature of 1000 - 1050 °C for 1 - 1.5 h, then raise the temperature to 1100 - 1120 °C and heat-treat for 1 - 1.5 h, then raise the temperature to 1150 - 1200 °C and heat-treat for 1 - 1.5 h. Then, under the condition that the rotational speed of the hole machine guide disk is 2 - 3 m / s, perform piercing treatment. Then, under the conditions of a rolling speed of 1.5 - 3 m / s and a temperature of 950 - 980 °C, roll the pipe to determine the diameter and obtain a sized pipe;

[0008] Step S2: Subject the sizing tube to quenching treatment for 15 - 20 min under the condition of a temperature of 850 - 900 °C, then conduct hot expansion for 20 - 30 min under the conditions of a temperature of 750 - 800 °C and a hot expansion speed of 30 - 35 mm / min, and then conduct tempering for 35 - 40 min under the condition of a temperature of 550 - 600 °C. After cooling to room temperature, spray the wear-resistant and corrosion-resistant coating onto the tube wall surface and conduct heat preservation treatment for 3 - 5 h under the condition of a temperature of 120 - 130 °C to obtain a thin-walled reducer.

[0009] Furthermore, the wear-resistant and corrosion-resistant coating comprises the following raw materials in parts by weight: 60 - 80 parts of enhanced resin emulsion, 15 - 20 parts of enhanced particles, 8 - 10 parts of aluminum tripolyphosphate, 2 - 3 parts of SN-154 defoamer, 1.5 - 2 parts of DH-3170 leveling agent, and 1 - 1.5 parts of sodium dodecylbenzenesulfonate.

[0010] Furthermore, the enhanced resin emulsion is prepared by the following steps:

[0011] Step A1: Mix KH550, tetrabutyl titanate, dimethyldiethoxysilane, and xylene uniformly. Under the conditions of a rotation speed of 200 - 300 r / min and a temperature of 70 - 80 °C, stir for 5 - 10 min, then add deionized water and hydrochloric acid solution and react for 3 - 5 h. Under the conditions of a pressure of 0.06 - 0.07 MPa and a temperature of 80 - 85 °C, distill to remove low-boiling substances, raise the temperature to 120 - 125 °C, and distill again to remove low-boiling substances to obtain an organosilicon resin.

[0012] The reaction process is as follows:

[0013]

[0014] Step A2: Mix 3,3',4,4'-benzophenone tetracarboxylic dianhydride and 1-methyl-2-pyrrolidone uniformly, introduce nitrogen protection and add 4,4'-diaminodiphenyl ether. Under the conditions of a rotation speed of 150 - 200 r / min and a temperature of 120 - 130 °C, react for 2 - 4 h, then raise the temperature to 175 - 185 °C and continue to react for 20 - 25 h to obtain polyimide.

[0015] The reaction process is as follows:

[0016]

[0017] Step A3: Mix polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, and acetone evenly. Under the conditions of a rotation speed of 200 - 300 r / min and a temperature of 80 - 85 °C, stir and add isophorone diisocyanate and dibutyltin dilaurate, and react for 5 - 7 h. Then add silicone resin and continue to react for 2 - 3 h to obtain an enhanced resin emulsion.

[0018] Further, the dosage ratio of KH550, tetrabutyl titanate, dimethyldiethoxysilane, xylene, deionized water, and hydrochloric acid solution described in Step A1 is 3.5 g : 6.8 g : 3.7 g : 20 mL : 100 mL : 0.5 mL, and the mass fraction of the hydrochloric acid solution is 36%.

[0019] Further, the dosage ratio of 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 1-methyl-2-pyrrolidone, and 4,4'-diaminodiphenyl ether described in Step A2 is 5 mmol : 30 mL : 6 mmol.

[0020] Further, the dosage ratio of polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, acetone, isophorone diisocyanate, dibutyltin dilaurate, and silicone resin described in Step A3 is 10 mmol : 10 mmol : 10 mmol : 10 mL : 20 mL : 8 mmol : 0.3 g : 5 mmol.

[0021] Further, the enhanced particles are prepared by the following steps:

[0022] Step B1: Mix graphene oxide, KH550, 1-hydroxybenzotriazole, and tetrahydrofuran evenly. Under the conditions of a rotation speed of 300 - 500 r / min and a temperature of 40 - 50 °C, react for 6 - 8 h. Filter to remove the filtrate. After drying the filter cake, disperse it in deionized water, add silicon carbide, adjust the pH value to 9 - 10, and under the conditions of a frequency of 30 - 50 kHz and a temperature of 60 - 70 °C, perform ultrasonic treatment for 5 - 7 h. Filter to remove the filtrate to obtain composite particles;

[0023] Step B2: Mix the composite particles, isophorone diisocyanate, and tetrahydrofuran, and under the conditions of a rotation speed of 150 - 200 r / min and a temperature of 20 - 30 °C, stir for 30 - 40 min. Filter to remove the filtrate to obtain modified composite particles. Mix pentaerythritol, epichlorohydrin, sodium carbonate, and deionized water, and under the condition of a rotation speed of 200 - 300 r / min, react for 3 - 5 h. Then adjust the pH value to alkaline and add ethylenediamine to react for 6 - 8 h to obtain a hyperbranched polymer;

[0024] Step B3: Mix the hyperbranched polymer, modified composite particles, and tetrahydrofuran, and stir for 6 - 8 h under the conditions of a rotation speed of 500 - 800 r / min and a temperature of 50 - 60 °C. Filter to remove the filtrate, and dry the filter cake to obtain enhanced particles.

[0025] Further, the dosage of KH550 in Step B1 is 5 - 8% of the mass of graphene oxide, and the dosage of silicon carbide is 15 - 20% of the mass of graphene oxide.

[0026] Further, the molar ratio of the carboxyl groups on the surface of the composite particles to the isocyanate groups on isophorone diisocyanate in Step B2 is 1:2, and the molar ratio of pentaerythritol, epichlorohydrin, and ethylenediamine is 1:4:2.3.

[0027] Further, the mass ratio of the hyperbranched polymer to the modified composite particles in Step B3 is 5:2.

[0028] Advantages of the present invention: To prepare a thin-walled variable-diameter pipe according to the present invention, a sized pipe is obtained after heating, piercing, tube rolling, and sizing the pipe blank; then, after quenching, hot expansion, and tempering the sized pipe, it is cooled to room temperature, and a wear-resistant and corrosion-resistant coating is sprayed on the pipe wall surface and subjected to heat preservation treatment. The wear-resistant and corrosion-resistant coating comprises the following raw materials in parts by weight: 60-80 parts of an enhanced resin emulsion, 15-20 parts of enhanced particles, 8-10 parts of aluminum tripolyphosphate, 2-3 parts of SN-154 defoamer, 1.5-2 parts of DH-3170 leveling agent, and 1-1.5 parts of sodium dodecylbenzenesulfonate. The enhanced resin emulsion is prepared by polymerizing KH550, tetrabutyl titanate, and dimethyldiethoxysilane to obtain an organosilicon resin. Then, 3,3',4,4'-benzophenone tetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether are polymerized to form a polyimide with amino groups at both ends. The polyimide, polycarbonate diol 1000, polyethylene glycol 1000, and isophorone diisocyanate are reacted to form a long chain with isocyanate groups at both ends. The isocyanate groups at both ends react with the amino groups on the side chain of the organosilicon resin molecule, and the remaining isophorone diisocyanate is grafted therein to obtain the enhanced resin emulsion. The enhanced particles are prepared by dehydrating graphene oxide with KH550, such that the carboxyl groups on the surface of graphene oxide react with the amino groups on KH550, so that a large amount of siloxane is grafted on the surface of graphene. Then, hydrolysis occurs in water and reacts with the hydroxyl groups on the surface of silicon carbide, such that silicon carbide adheres to the surface of graphene to obtain composite particles. The composite particles are reacted with isophorone diisocyanate to graft isocyanate groups on the surface. Pentaerythritol and epichlorohydrin are reacted such that the alcohol hydroxyl groups on pentaerythritol react with the chlorine atom sites on epichlorohydrin, and then reacted with ethylenediamine to form a hyperbranched polymer. During the reaction between amino groups and epoxy groups, a large number of hydroxyl groups are generated in the hyperbranched polymer molecules. The hydroxyl groups further react with the isocyanate groups on the modified composite particles, such that a grid-like polymer is coated on the particle surface to obtain the enhanced particles. When the enhanced resin emulsion and the enhanced particles are blended, the hydroxyl groups on the surface of the enhanced particles react with the isocyanate groups in the enhanced resin emulsion molecules for capping, such that the coating is cured. The molecular chain of the enhanced resin emulsion contains an organosilicon side chain, and at the same time, the organosilicon molecule contains titanium, such that the wear resistance of the prepared enhanced resin is improved. The enhanced particles are based on graphene and silicon carbide, and the compounding with the enhanced resin further improves the wear resistance of the coating. At the same time, the surface of the enhanced particles is wrapped by a hyperbranched polymer, such that during the blending process of the enhanced particles and the enhanced resin emulsion, they can be quickly and uniformly dispersed, and at the same time, the corrosion resistance of the variable-diameter pipe is enhanced, and the service life of the variable-diameter pipe is extended. Detailed implementation manners

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] Embodiment 1

[0031] A production process for a thin-walled reducing pipe specifically includes the following steps:

[0032] Step S1: Heat the tube blank at a temperature of 1000 °C for 1 h, then raise the temperature to 1100 °C and heat for 1 h, then raise the temperature to 1150 °C and heat for 1 h. Then, under the condition that the rotational speed of the hole machine guide disk is 2 m / s, perform piercing treatment. Then, under the conditions of a rolling speed of 1.5 m / s and a temperature of 950 °C, perform tube rolling and sizing to obtain a sized tube.

[0033] Step S2: Quench the sized tube at a temperature of 850 °C for 15 min. Then, under the conditions of a temperature of 750 °C and a hot expansion speed of 30 mm / min, perform hot expansion for 20 min. Then, under the condition of a temperature of 550 °C, perform tempering for 35 min and then cool to room temperature. Spray the wear-resistant and corrosion-resistant coating on the surface of the tube wall, and perform heat preservation treatment at a temperature of 120 °C for 3 h to obtain a thin-walled reducing pipe.

[0034] The wear-resistant and corrosion-resistant coating includes the following raw materials in parts by weight: 60 parts of enhanced resin emulsion, 15 parts of enhanced particles, 8 parts of aluminum tripolyphosphate, 2 parts of SN-154 defoamer, 1.5 parts of DH-3170 leveling agent, and 1 part of sodium dodecylbenzenesulfonate.

[0035] The enhanced resin emulsion is prepared by the following steps:

[0036] Step A1: Mix KH550, tetrabutyl titanate, dimethyldiethoxysilane, and xylene evenly. Under the conditions of a rotational speed of 200 r / min and a temperature of 70 °C, stir for 5 min, then add deionized water and hydrochloric acid solution, and react for 3 h. Then, under the conditions of a pressure of 0.06 MPa and a temperature of 80 °C, distill to remove low-boiling substances, raise the temperature to 120 °C, and distill again to remove low-boiling substances to obtain an organosilicon resin.

[0037] Step A2: Mix 3,3',4,4'-benzophenone tetracarboxylic dianhydride and 1-methyl-2-pyrrolidone evenly, introduce nitrogen protection and add 4,4'-diaminodiphenyl ether. Under the conditions of a rotational speed of 150 r / min and a temperature of 120 °C, react for 2 h, then raise the temperature to 175 °C and continue to react for 20 h to obtain polyimide.

[0038] Step A3: Mix polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, and acetone evenly. Under the conditions of a rotation speed of 200 r / min and a temperature of 80 °C, stir and add isophorone diisocyanate and dibutyltin dilaurate, and react for 5 h. Then add silicone resin and continue to react for 2 h to obtain an enhanced resin emulsion.

[0039] The dosage ratio of KH550, tetrabutyl titanate, dimethyldiethoxysilane, xylene, deionized water, and hydrochloric acid solution described in Step A1 is 3.5 g: 6.8 g: 3.7 g: 20 mL: 100 mL: 0.5 mL, and the mass fraction of the hydrochloric acid solution is 36%.

[0040] The dosage ratio of 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 1-methyl-2-pyrrolidone, and 4,4'-diaminodiphenyl ether described in Step A2 is 5 mmol: 30 mL: 6 mmol.

[0041] The dosage ratio of polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, acetone, isophorone diisocyanate, dibutyltin dilaurate, and silicone resin described in Step A3 is 10 mmol: 10 mmol: 10 mmol: 10 mL: 20 mL: 8 mmol: 0.3 g: 5 mmol.

[0042] The described enhanced particles are prepared by the following steps:

[0043] Step B1: Mix graphene oxide, KH550, 1-hydroxybenzotriazole, and tetrahydrofuran evenly. Under the conditions of a rotation speed of 300 r / min and a temperature of 40 °C, react for 6 h. Filter to remove the filtrate. After drying the filter cake, disperse it in deionized water, add silicon carbide, adjust the pH value to 9, and under the conditions of a frequency of 30 kHz and a temperature of 60 °C, perform ultrasonic treatment for 5 h. Filter to remove the filtrate to obtain composite particles.

[0044] Step B2: Mix the composite particles, isophorone diisocyanate, and tetrahydrofuran, and stir at a rotation speed of 150 r / min and a temperature of 20 °C for 30 min. Filter to remove the filtrate to obtain modified composite particles. Mix pentaerythritol, epichlorohydrin, sodium carbonate, and deionized water, and react at a rotation speed of 200 r / min for 3 h. Then adjust the pH value to alkaline and add ethylenediamine to react for 6 h to obtain a hyperbranched polymer.

[0045] Step B3: Mix the hyperbranched polymer, modified composite particles, and tetrahydrofuran, and stir for 6 h under the conditions of a rotation speed of 500 r / min and a temperature of 50 °C. Filter to remove the filtrate, and dry the filter cake to obtain the reinforcing particles.

[0046] The dosage of KH550 described in Step B1 is 5% of the mass of graphene oxide, and the dosage of silicon carbide is 15% of the mass of graphene oxide.

[0047] The molar ratio of the carboxyl groups on the surface of the composite particles described in Step B2 to the isocyanate groups on isophorone diisocyanate is 1:2, and the molar ratio of pentaerythritol, epichlorohydrin, and ethylenediamine is 1:4:2.3.

[0048] The mass ratio of the hyperbranched polymer to the modified composite particles described in Step B3 is 5:2.

[0049] Example 2

[0050] A production process for a thin-walled reducing pipe specifically includes the following steps:

[0051] Step S1: Heat-treat the tube blank at a temperature of 1030 °C for 1.3 h, then raise the temperature to 1110 °C and heat-treat for 1.3 h, then raise the temperature to 1180 °C and heat-treat for 1.3 h. Then, perform piercing treatment under the condition that the rotation speed of the hole machine guide disc is 2 m / s, and then perform tube sizing at a rolling speed of 2 m / s and a temperature of 970 °C to obtain the sized tube.

[0052] Step S2: Quench the sized tube at a temperature of 880 °C for 18 min, then perform hot expansion at a temperature of 780 °C and a hot expansion speed of 35 mm / min for 25 min. Then, perform tempering at a temperature of 580 °C for 35 min and then cool to room temperature. Spray the wear-resistant and anticorrosive coating on the tube wall surface, and perform heat preservation treatment at a temperature of 125 °C for 4 h to obtain the thin-walled reducing pipe.

[0053] The wear-resistant and anticorrosive coating includes the following raw materials in parts by weight: 70 parts of reinforcing resin emulsion, 18 parts of reinforcing particles, 9 parts of aluminum tripolyphosphate, 2.5 parts of SN-154 defoamer, 1.8 parts of DH-3170 leveling agent, and 1.3 parts of sodium dodecylbenzenesulfonate.

[0054] The reinforcing resin emulsion is prepared by the following steps:

[0055] Step A1: Mix KH550, tetrabutyl titanate, dimethyldiethoxysilane, and xylene evenly. Under the conditions of a rotation speed of 200 r / min and a temperature of 75 °C, stir for 8 min, then add deionized water and hydrochloric acid solution, and react for 4 h. Under the conditions of a pressure of 0.07 MPa and a temperature of 83 °C, distill to remove low-boiling substances. Raise the temperature to 123 °C and distill again to remove low-boiling substances to obtain silicone resin.

[0056] Step A2: Mix 3,3',4,4'-benzophenone tetracarboxylic dianhydride and 1-methyl-2-pyrrolidone evenly, introduce nitrogen protection and add 4,4'-diaminodiphenyl ether. Under the conditions of a rotation speed of 180 r / min and a temperature of 125 °C, react for 3 h, then raise the temperature to 180 °C and continue to react for 23 h to obtain polyimide.

[0057] Step A3: Mix polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, and acetone evenly. Under the conditions of a rotation speed of 200 r / min and a temperature of 83 °C, stir and add isophorone diisocyanate and dibutyltin dilaurate, and react for 6 h. Then add silicone resin and continue to react for 2.5 h to obtain an enhanced resin emulsion.

[0058] The dosage ratios of KH550, tetrabutyl titanate, dimethyldiethoxysilane, xylene, deionized water, and hydrochloric acid solution described in Step A1 are 3.5 g: 6.8 g: 3.7 g: 20 mL: 100 mL: 0.5 mL, and the mass fraction of the hydrochloric acid solution is 36%.

[0059] The dosage ratios of 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 1-methyl-2-pyrrolidone, and 4,4'-diaminodiphenyl ether described in Step A2 are 5 mmol: 30 mL: 6 mmol.

[0060] The dosage ratios of polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, acetone, isophorone diisocyanate, dibutyltin dilaurate, and silicone resin described in Step A3 are 10 mmol: 10 mmol: 10 mmol: 10 mL: 20 mL: 8 mmol: 0.3 g: 5 mmol.

[0061] The described reinforcing particles are prepared by the following steps:

[0062] Step B1: Mix graphene oxide, KH550, 1-hydroxybenzotriazole, and tetrahydrofuran evenly. React for 7 h under the conditions of a rotation speed of 300 r / min and a temperature of 45 °C. Filter to remove the filtrate. After drying the filter cake, disperse it in deionized water, add silicon carbide, adjust the pH value to 10, and perform ultrasonic treatment for 6 h under the conditions of a frequency of 40 kHz and a temperature of 65 °C. Filter to remove the filtrate to obtain composite particles.

[0063] Step B2: Mix the composite particles, isophorone diisocyanate, and tetrahydrofuran, and stir for 35 min under the conditions of a rotation speed of 180 r / min and a temperature of 25 °C. Filter to remove the filtrate to obtain modified composite particles. Mix pentaerythritol, epichlorohydrin, sodium carbonate, and deionized water, react for 4 h under the condition of a rotation speed of 200 r / min, then adjust the pH value to be alkaline, and add ethylenediamine to react for 7 h to obtain a hyperbranched polymer.

[0064] Step B3: Mix the hyperbranched polymer, modified composite particles, and tetrahydrofuran, and stir for 7 h under the conditions of a rotation speed of 800 r / min and a temperature of 55 °C. Filter to remove the filtrate and dry the filter cake to obtain enhanced particles.

[0065] The dosage of KH550 described in Step B1 is 6% of the mass of graphene oxide, and the dosage of silicon carbide is 18% of the mass of graphene oxide.

[0066] The molar ratio of the carboxyl group on the surface of the composite particles to the isocyanate group on isophorone diisocyanate described in Step B2 is 1:2, and the molar ratio of pentaerythritol, epichlorohydrin, and ethylenediamine is 1:4:2.3.

[0067] The mass ratio of the hyperbranched polymer to the modified composite particles described in Step B3 is 5:2.

[0068] Example 3

[0069] A production process for a thin-walled variable-diameter pipe specifically includes the following steps:

[0070] Step S1: Heat-treat the tube blank at a temperature of 1050 °C for 1.5 h, then raise the temperature to 1120 °C and heat-treat for 1.5 h, then raise the temperature to 1200 °C and heat-treat for 1.5 h. Then, perform piercing treatment under the condition that the rotation speed of the hole machine guide disc is 3 m / s, and then perform tube sizing under the conditions of a rolling speed of 3 m / s and a temperature of 980 °C to obtain a sized tube.

[0071] Step S2: Subject the sizing tube to quenching treatment for 20 min at 900 °C, then perform hot expansion for 30 min at 800 °C with a hot expansion speed of 35 mm / min, and then perform tempering for 40 min at 600 °C, and cool to room temperature. Spray the wear-resistant and corrosion-resistant coating on the surface of the pipe wall, and perform heat preservation treatment for 5 h at 130 °C to obtain a thin-walled reducer.

[0072] The wear-resistant and corrosion-resistant coating described above comprises raw materials in the following weight parts: 80 parts of enhanced resin emulsion, 20 parts of enhanced particles, 10 parts of aluminum tripolyphosphate, 3 parts of SN-154 defoamer, 2 parts of DH-3170 leveling agent, and 1.5 parts of sodium dodecylbenzenesulfonate.

[0073] The enhanced resin emulsion is prepared by the following steps:

[0074] Step A1: Mix KH550, tetrabutyl titanate, dimethyldiethoxysilane, and xylene evenly. Under the conditions of a rotation speed of 300 r / min and a temperature of 80 °C, stir for 10 min, then add deionized water and hydrochloric acid solution, and react for 5 h. Under the conditions of a pressure of 0.07 MPa and a temperature of 85 °C, distill to remove low-boiling substances, raise the temperature to 125 °C, and distill again to remove low-boiling substances to obtain an organosilicon resin.

[0075] Step A2: Mix 3,3',4,4'-benzophenone tetracarboxylic dianhydride and 1-methyl-2-pyrrolidone evenly, introduce nitrogen protection and add 4,4'-diaminodiphenyl ether. Under the conditions of a rotation speed of 200 r / min and a temperature of 130 °C, react for 4 h, then raise the temperature to 185 °C and continue to react for 25 h to obtain polyimide.

[0076] Step A3: Mix polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, and acetone evenly. Under the conditions of a rotation speed of 300 r / min and a temperature of 85 °C, stir and add isophorone diisocyanate and dibutyltin dilaurate, react for 7 h, then add the organosilicon resin and continue to react for 3 h to obtain the enhanced resin emulsion.

[0077] The dosage ratio of KH550, tetrabutyl titanate, dimethyldiethoxysilane, xylene, deionized water, and hydrochloric acid solution in Step A1 is 3.5 g: 6.8 g: 3.7 g: 20 mL: 100 mL: 0.5 mL, and the mass fraction of the hydrochloric acid solution is 36%.

[0078] The dosage ratio of 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 1-methyl-2-pyrrolidone, and 4,4'-diaminodiphenyl ether in Step A2 is 5 mmol: 30 mL: 6 mmol.

[0079] The dosage ratio of the polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, acetone, isophorone diisocyanate, dibutyltin dilaurate, and silicone resin described in step A3 is 10 mmol: 10 mmol: 10 mmol: 10 mL: 20 mL: 8 mmol: 0.3 g: 5 mmol.

[0080] The described reinforcing particles are made by the following steps:

[0081] Step B1: Mix graphene oxide, KH550, 1-hydroxybenzotriazole, and tetrahydrofuran evenly. React for 8 h under the conditions of a rotation speed of 500 r / min and a temperature of 50 °C. Filter to remove the filtrate. After drying the filter cake, disperse it in deionized water, add silicon carbide, adjust the pH value to 10, and perform ultrasonic treatment for 7 h under the conditions of a frequency of 50 kHz and a temperature of 70 °C. Filter to remove the filtrate to obtain composite particles;

[0082] Step B2: Mix the composite particles, isophorone diisocyanate, and tetrahydrofuran, and stir for 40 min under the conditions of a rotation speed of 200 r / min and a temperature of 30 °C. Filter to remove the filtrate to obtain modified composite particles. Mix pentaerythritol, epichlorohydrin, sodium carbonate, and deionized water, and react for 5 h under the condition of a rotation speed of 300 r / min. Then adjust the pH value to alkaline and add ethylenediamine to react for 8 h to obtain a hyperbranched polymer;

[0083] Step B3: Mix the hyperbranched polymer, modified composite particles, and tetrahydrofuran, and stir for 8 h under the conditions of a rotation speed of 800 r / min and a temperature of 60 °C. Filter to remove the filtrate and dry the filter cake to obtain reinforcing particles.

[0084] The dosage of KH550 described in step B1 is 8% of the mass of graphene oxide, and the dosage of silicon carbide is 20% of the mass of graphene oxide.

[0085] The molar ratio of the carboxyl groups on the surface of the composite particles to the isocyanate groups on isophorone diisocyanate described in step B2 is 1:2, and the molar ratio of pentaerythritol, epichlorohydrin, and ethylenediamine is 1:4:2.3.

[0086] The mass ratio of the hyperbranched polymer to the modified composite particles described in step B3 is 5:2.

[0087] Comparative Example 1

[0088] This comparative example is the wear-resistant and anticorrosive coating disclosed in Chinese Patent CN111925695A.

[0089] Comparative Example 2

[0090] This comparative example is the wear-resistant and corrosion-resistant coating disclosed in Chinese Patent CN109777262A.

[0091] The wear rates of the wear-resistant and corrosion-resistant coatings prepared in Examples 1-3 and Comparative Examples 1-2 were detected according to the standard of GB / T23988-2009, and the corrosion resistance test was carried out according to the standard of GB / T9274-1988. The results are shown in the following table;

[0092]

[0093] It can be seen from the above table that the reducing pipes prepared in Examples 1-3 have good friction and corrosion resistance, and can improve their own service life.

[0094] The above content is only an example and illustration of the concept of the present invention. Those skilled in the art of the present technology can make various modifications or supplements to the described specific embodiments or use similar methods to replace them. As long as they do not deviate from the concept of the invention or exceed the scope defined by this claim book, they should all belong to the protection scope of the present invention.

Claims

1. A production process for a thin-walled reducer, characterized in that: Specifically, it includes the following steps: Step S1: After heating, piercing, tube rolling, and sizing the tube blank, a sized tube is obtained; Step S2: After quenching, hot expansion, and tempering the sized tube, it is cooled to room temperature, a wear-resistant and corrosion-resistant coating is sprayed on the tube wall surface, and heat preservation treatment is carried out to obtain a thin-walled reducing tube; The wear-resistant and corrosion-resistant coating includes the following raw materials in parts by weight: 60 - 80 parts of enhanced resin emulsion, 15 - 20 parts of enhanced particles, 8 - 10 parts of aluminum tripolyphosphate, 2 - 3 parts of SN-154 defoamer, 1.5 - 2 parts of DH-3170 leveling agent, and 1 - 1.5 parts of sodium dodecylbenzenesulfonate; The enhanced resin emulsion is prepared by the following steps: Step A1: After mixing and stirring KH550, tetrabutyl titanate, dimethyldiethoxysilane, and xylene, deionized water and hydrochloric acid solution are added, and after reaction, low-boiling substances are removed by distillation, and the temperature is raised and low-boiling substances are removed by distillation again to obtain an organosilicon resin; Step A2: After uniformly mixing 3,3',4,4'-benzophenone tetracarboxylic dianhydride and 1-methyl-2-pyrrolidone, nitrogen is introduced for protection and 4,4'-diaminodiphenyl ether is added, and after reaction, the temperature is raised and the reaction continues to obtain polyimide; Step A3: After mixing and stirring polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, and acetone, isophorone diisocyanate and dibutyltin dilaurate are added, and after reaction, the organosilicon resin is added and the reaction continues to obtain an enhanced resin emulsion.

2. The production process for a thin-walled reducer according to claim 1, characterized in that: The dosage ratio of KH550, tetrabutyl titanate, dimethyldiethoxysilane, xylene, deionized water, and hydrochloric acid solution in Step A1 is 3.5 g:6.8 g:3.7 g:20 mL:100 mL:0.5 mL, and the mass fraction of the hydrochloric acid solution is 36%.

3. The production process for a thin-walled reducer according to claim 1, characterized in that: The dosage ratio of 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 1-methyl-2-pyrrolidone, and 4,4'-diaminodiphenyl ether in Step A2 is 5 mmol:30 mL:6 mmol.

4. The production process for a thin-walled reducer according to claim 1, characterized in that: The dosage ratio of polyimide, polycarbonate diol 1000, polyethylene glycol 1000, 1-methyl-2-pyrrolidone, acetone, isophorone diisocyanate, dibutyltin dilaurate, and organosilicon resin in Step A3 is 10 mmol:10 mmol:10 mmol:10 mL:20 mL:8 mmol:0.3 g:5 mmol.

5. The production process for a thin-walled reducer according to claim 1, characterized in that: The enhanced particles are prepared by the following steps: Step B1: After reacting graphene oxide, KH550, 1-hydroxybenzotriazole, and tetrahydrofuran, the filtrate is removed by filtration. After drying the filter cake, it is dispersed in deionized water, silicon carbide is added, the pH value is adjusted, and ultrasonic treatment is carried out. The filtrate is removed by filtration to obtain composite particles; Step B2: After mixing and stirring the composite particles, isophorone diisocyanate, and tetrahydrofuran, the filtrate is removed by filtration to obtain modified composite particles. Pentaerythritol, epichlorohydrin, sodium carbonate, and deionized water are mixed and reacted, the pH value is adjusted to be alkaline, and ethylenediamine is added for reaction to obtain a hyperbranched polymer; Step B3: Mix and stir the hyperbranched polymer, modified composite particles, and tetrahydrofuran, filter to remove the filtrate, and dry the filter cake to obtain enhanced particles.

6. The production process for a thin-walled reducer according to claim 5, characterized in that: In Step B1, the dosage of KH550 is 5-8% of the mass of graphene oxide, and the dosage of silicon carbide is 15-20% of the mass of graphene oxide.

7. The production process for a thin-walled reducer according to claim 5, characterized in that: In Step B2, the molar ratio of the carboxyl groups on the surface of the composite particles to the isocyanate groups on isophorone diisocyanate is 1:2, and the molar ratio of pentaerythritol, epichlorohydrin, and ethylenediamine is 1:4:2.

3.

8. The production process for a thin-walled reducer according to claim 5, characterized in that: In Step B3, the mass ratio of the hyperbranched polymer to the modified composite particles is 5:2.

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