Surface modification method for pressure reducer shell

Abstract

The invention discloses a pressure reducer shell surface modification method, which belongs to the technical field of pressure reducer shell processing, and comprises the following steps: (1) surface oil removal and cleaning treatment, (2) surface shot blasting treatment, (3) surface electric arc spraying treatment, and (4) cooling treatment. The treatment process is simple in step and reasonable in matching, the surface characteristics of the pressure reducer shell are effectively enhanced, the corrosion resistance and weather resistance of the pressure reducer shell are remarkably enhanced, and the service life of the pressure reducer shell is effectively prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of pressure reducer shell processing, in particular to a surface modification method of a pressure reducer shell. Background Art

[0002] Stainless steel is one of the indispensable raw materials in modern people's lives. It is widely used in building materials, mechanical equipment, automobile manufacturing and other fields. Of course, the most commonly used raw material for the reducer housing is also stainless steel. However, due to the poor corrosion resistance of steel itself, it needs to be surface treated before it can be used. There are many methods for treating the surface of stainless steel, spraying technology is one of them, and arc spraying is currently a more popular spraying technology. Its spraying quality is relatively stable, the cost is low, the safety is good, and the production efficiency is high. However, arc spraying relies on the stacking of molten metal particles on the surface of the workpiece. The stacking and bonding will produce a certain gap under the action of external force. At the same time, residual stress is easy to remain in the coating, and the bite and bonding ability with the workpiece substrate is still not high. The process treatment effect still needs further improvement. Summary of the invention

[0003] The purpose of the present invention is to provide a method for modifying the surface of a pressure reducer housing to solve the deficiencies in the prior art.

[0004] The technical solution adopted by the present invention is as follows: A method for modifying the surface of a pressure reducer housing comprises the following steps: (1) Surface degreasing and cleaning: Immerse the pressure reducer housing in industrial degreasing agent, soak for 10-15 minutes, then take it out, rinse it with deionized water 2-3 times, and dry it for later use; (2) Surface shot peening: Shot peening is performed on the surface of the pressure reducer housing after the treatment in step (1), and after the treatment is completed, the housing is taken out for use; (3) Surface arc spraying treatment: Perform arc spraying on the surface of the pressure reducer housing after the treatment in step (2), and continue ultrasonic treatment during the process, and take it out for use after completion; (4) Cooling treatment: The pressure reducer housing treated in step (3) is placed in a temperature-variable box for cooling until it cools to room temperature and then taken out.

[0005] Furthermore, the industrial degreasing agent in step (1) is acetone; and the temperature of the industrial degreasing agent is controlled to be 32-36°C during the immersion treatment.

[0006] Furthermore, the blasting medium used in the shot blasting in step (2) is corundum sand, and the particle size of the corundum sand is 250 mesh.

[0007] Furthermore, during the ultrasonic treatment in step (3), the frequency of the ultrasonic wave is controlled to be 600-650 kHz.

[0008] Furthermore, during the arc spraying treatment in step (3), the current is controlled to be 120-124A, the jet pressure is controlled to be 0.65-0.75MPa, and the spraying angle is 90°.

[0009] Furthermore, the spraying powder used in the arc spraying treatment in step (3) is composed of the following raw materials in corresponding parts by weight: 45-50 parts of nickel-chromium powder, 18-22 parts of ferroboron powder, 4-7 parts of ferrosilicon-zirconium powder, 6-9 parts of aluminum powder, 3-6 parts of magnesium powder, 5-8 parts of ferromanganese powder, and 7-10 parts of reinforcing powder.

[0010] Furthermore, the preparation method of the reinforcing powder comprises the following steps: a. Mix graphite powder, nano titanium nitride and nano cordierite powder together and put them into a ball mill, then add a modifier into the ball mill, and continue to ball mill for 2-3 hours before taking out the mixture for use; during ball milling, with the cooperation of the modifier, nano titanium nitride and nano cordierite powder effectively penetrate into the graphite powder layer to form a mixed filler. This component can be firmly combined with the surface of the pressure reducer shell during arc spraying to form a more complex and stable enhanced alloy phase structure, especially nano cordierite powder can form mullite phase, and nano titanium nitride improves the density and stability of the surface of the pressure reducer shell; b. Place the mixture obtained in step a into a centrifuge for centrifugal treatment, and then dry the obtained centrifuged material, and then take it out.

[0011] Furthermore, the graphite powder described in step a is mixed with nano titanium nitride and nano cordierite powder in a corresponding weight ratio of 15-18:2-4:1-3; the amount of the modifier added is 5-7 times the total mass of the graphite powder; the modifier is composed of the following corresponding weight portions of substances: 6-8 parts of hexadecyltrimethylammonium bromide, 3-6 parts of sodium pyrophosphate, 2-5 parts of zinc stearate, and 100-120 parts of deionized water.

[0012] Furthermore, during the centrifugal treatment in step b, the rotation speed of the centrifuge is controlled to be 4000-5000 rpm; during the drying treatment, the drying temperature is controlled to be 100-110°C.

[0013] The present invention has the following beneficial effects: The treatment process of the present invention is simple in steps and reasonable in matching, and the surface characteristics of the pressure reducer housing are effectively enhanced. In the treatment process, the surface is firstly degreased and cleaned to remove impurities on the surface of the material, and then the surface is shot peened. The shot peening is used to refine the size of the surface grains of the material, and at the same time, the surface roughness and hardness of the material are appropriately improved, which is beneficial to the subsequent processing. Then, the surface is arc sprayed. In the arc spraying process, a special spraying powder component is used. The spraying powder is mainly composed of nickel-chromium powder, ferroboron powder, silicon-zirconium-iron powder, aluminum powder, magnesium powder, and ferromanganese powder, and is supplemented with reinforcing powder to enhance the performance. The reinforcing powder is modified from graphite powder. The obtained reinforcing powder can form a metallographic structure with strong hardness, strength and corrosion resistance under high temperature conditions, significantly improves the stability and weather resistance of the arc spraying layer, etc., thereby improving the surface characteristics of the pressure reducer housing, and finally the finished pressure reducer housing is obtained through cooling. After the pressure reducer shell is treated by the treatment process of the present invention, the corrosion resistance and weather resistance of the pressure reducer shell can be significantly enhanced, and its service life is effectively extended, which has great promotion and application value. DETAILED DESCRIPTION

[0014] The following will be described clearly and completely in conjunction with the technical solutions of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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.

[0015] A method for modifying the surface of a pressure reducer housing comprises the following steps: (1) Surface degreasing and cleaning: Immerse the pressure reducer housing in industrial degreasing agent, soak for 10-15 minutes, then take it out, rinse it with deionized water 2-3 times, and dry it for later use; (2) Surface shot peening: Shot peening is performed on the surface of the pressure reducer housing after the treatment in step (1), and after the treatment is completed, the housing is taken out for use; (3) Surface arc spraying treatment: Perform arc spraying on the surface of the pressure reducer housing after the treatment in step (2), and continue ultrasonic treatment during the process, and take it out for use after completion; (4) Cooling treatment: The pressure reducer housing treated in step (3) is placed in a temperature-variable box for cooling until it cools to room temperature and then taken out.

[0016] The industrial degreasing agent described in step (1) is acetone; during the immersion treatment, the temperature of the industrial degreasing agent is controlled to be 32-36°C.

[0017] The blasting medium used in the shot blasting process described in step (2) is corundum sand, and the particle size of the corundum sand is 250 mesh.

[0018] During the ultrasonic treatment in step (3), the frequency of the ultrasonic wave is controlled to be 600-650 kHz.

[0019] During the arc spraying treatment in step (3), the current is controlled to be 120-124A, the jet pressure is 0.65-0.75MPa, and the spraying angle is 90°.

[0020] The spraying powder used in the arc spraying treatment described in step (3) is composed of the following raw materials in corresponding parts by weight: 45-50 parts of nickel-chromium powder, 18-22 parts of ferroboron powder, 4-7 parts of ferrosilicon-zirconium powder, 6-9 parts of aluminum powder, 3-6 parts of magnesium powder, 5-8 parts of ferromanganese powder, and 7-10 parts of reinforcing powder.

[0021] The preparation method of the reinforcing powder comprises the following steps: a. Mix graphite powder, nano titanium nitride and nano cordierite powder and put them into a ball mill. Then add a modifier into the ball mill. Continue to ball mill for 2-3 hours and then take out the mixture for use. b. Place the mixture obtained in step a into a centrifuge for centrifugal treatment, and then dry the obtained centrifuged material, and then take it out.

[0022] The graphite powder described in step a is mixed with nano titanium nitride and nano cordierite powder in a corresponding weight ratio of 15-18:2-4:1-3; the amount of the modifier added is 5-7 times the total mass of the graphite powder; the modifier is composed of the following corresponding weight parts: 6-8 parts of hexadecyltrimethylammonium bromide, 3-6 parts of sodium pyrophosphate, 2-5 parts of zinc stearate, and 100-120 parts of deionized water.

[0023] During the centrifugal treatment in step b, the speed of the centrifuge is controlled to be 4000-5000 rpm; during the drying treatment, the drying temperature is controlled to be 100-110°C. Example 1

[0024] A method for modifying the surface of a pressure reducer housing comprises the following steps: (1) Surface degreasing and cleaning: Immerse the reducer housing in industrial degreasing agent - acetone, heat and maintain the temperature at 32°C, soak for 10 minutes, take it out, rinse it with deionized water twice, and dry it for later use; (2) Surface shot peening: The surface of the pressure reducer housing treated in step (1) is subjected to shot peening treatment, wherein the blasting medium used is corundum sand, and the particle size of the corundum sand is 250 meshes. After the treatment, the housing is taken out for use; (3) Surface arc spraying treatment: The surface of the pressure reducer housing treated in step (2) is subjected to arc spraying treatment, with the current controlled to be 120A, the jet pressure to be 0.65MPa, the spraying angle to be 90°, and ultrasonic treatment to be continuously performed during the treatment, with the ultrasonic frequency controlled to be 600kHz. After completion, the housing is taken out for use; the spraying powder used is composed of the following raw materials in corresponding parts by weight: 45 parts of nickel-chromium powder, 18 parts of ferroboron powder, 4 parts of ferrosilicon-zirconium powder, 6 parts of aluminum powder, 3 parts of magnesium powder, 5 parts of ferromanganese powder, and 7 parts of reinforcing powder; (4) Cooling treatment: The pressure reducer housing treated in step (3) is placed in a temperature-variable box for cooling until it cools to room temperature and then taken out.

[0025] The preparation method of the reinforcing powder comprises the following steps: a. Mix graphite powder, nano titanium nitride and nano cordierite powder together and put them into a ball mill, then add a modifier into the ball mill, and continue ball milling for 2 hours before taking out the mixture for use; the corresponding weight ratio of the graphite powder, nano titanium nitride and nano cordierite powder when mixed together is 15:2:1; the amount of the modifier added is 5 times the total mass of the graphite powder; the modifier is composed of the following corresponding weight parts: 6 parts of hexadecyltrimethylammonium bromide, 3 parts of sodium pyrophosphate, 2 parts of zinc stearate, and 100 parts of deionized water; b. Place the mixture obtained in step a into a centrifuge for centrifugal treatment, and then dry the centrifuged material to complete the removal; the speed of the centrifuge is controlled to be 4000 rpm during the centrifugal treatment; the drying temperature is controlled to be 100°C during the drying treatment. Example 2

[0026] A method for modifying the surface of a pressure reducer housing comprises the following steps: (1) Surface degreasing and cleaning: Immerse the reducer housing in acetone, an industrial degreasing agent, and heat it to maintain a temperature of 34°C. Take it out after soaking for 13 minutes, rinse it twice with deionized water, and dry it for later use. (2) Surface shot peening: The surface of the pressure reducer housing treated in step (1) is subjected to shot peening treatment, wherein the blasting medium used is corundum sand, and the particle size of the corundum sand is 250 meshes. After the treatment, the housing is taken out for use; (3) Surface arc spraying treatment: The surface of the pressure reducer housing treated in step (2) is subjected to arc spraying treatment, with the current controlled to be 122A, the jet pressure to be 0.70MPa, the spraying angle to be 90°, and ultrasonic treatment to be continuously performed during the treatment, with the ultrasonic frequency controlled to be 630kHz. After completion, the housing is taken out for use; the spraying powder used is composed of the following raw materials in corresponding parts by weight: 48 parts of nickel-chromium powder, 20 parts of ferroboron powder, 6 parts of ferrosilicon-zirconium powder, 8 parts of aluminum powder, 5 parts of magnesium powder, 7 parts of ferromanganese powder, and 9 parts of reinforcing powder; (4) Cooling treatment: The pressure reducer housing treated in step (3) is placed in a temperature-variable box for cooling until it cools to room temperature and then taken out.

[0027] The preparation method of the reinforcing powder comprises the following steps: a. Mix graphite powder, nano titanium nitride and nano cordierite powder together and put them into a ball mill, then add a modifier into the ball mill, and continue ball milling for 2.5 hours before taking out the mixture for use; the corresponding weight ratio of the graphite powder, nano titanium nitride and nano cordierite powder when mixed together is 17:3:2; the amount of the modifier added is 6 times the total mass of the graphite powder; the modifier is composed of the following corresponding weight parts: 7 parts of hexadecyltrimethylammonium bromide, 5 parts of sodium pyrophosphate, 4 parts of zinc stearate, and 110 parts of deionized water; b. Place the mixture obtained in step a into a centrifuge for centrifugal treatment, and then dry the centrifuged material until it is taken out; the speed of the centrifuge is controlled to be 4500 rpm during the centrifugal treatment; the drying temperature is controlled to be 105°C during the drying treatment. Example 3

[0028] A method for modifying the surface of a pressure reducer housing comprises the following steps: (1) Surface degreasing and cleaning: Immerse the reducer housing in industrial degreasing agent - acetone, heat and maintain the temperature at 36°C, soak for 15 minutes, take it out, rinse it with deionized water 3 times, and dry it for later use; (2) Surface shot peening: The surface of the pressure reducer housing treated in step (1) is subjected to shot peening treatment, wherein the blasting medium used is corundum sand, and the particle size of the corundum sand is 250 meshes. After the treatment, the housing is taken out for use; (3) Surface arc spraying treatment: The surface of the pressure reducer housing treated in step (2) is subjected to arc spraying treatment, with the current controlled to be 124A, the jet pressure to be 0.75MPa, the spraying angle to be 90°, and ultrasonic treatment to be continuously performed during the treatment, with the ultrasonic frequency controlled to be 650kHz. After completion, the housing is taken out for use; the spraying powder used is composed of the following raw materials in corresponding parts by weight: 50 parts of nickel-chromium powder, 22 parts of ferroboron powder, 7 parts of ferrosilicon-zirconium powder, 9 parts of aluminum powder, 6 parts of magnesium powder, 8 parts of ferromanganese powder, and 10 parts of reinforcing powder; (4) Cooling treatment: The pressure reducer housing treated in step (3) is placed in a temperature-variable box for cooling until it cools to room temperature and then taken out.

[0029] The preparation method of the reinforcing powder comprises the following steps: a. Mix graphite powder, nano titanium nitride and nano cordierite powder together and put them into a ball mill, then add a modifier into the ball mill, and continue ball milling for 3 hours before taking out the mixture for use; the corresponding weight ratio of the graphite powder, nano titanium nitride and nano cordierite powder when mixed together is 18:4:3; the amount of the modifier added is 7 times the total mass of the graphite powder; the modifier is composed of the following corresponding weight parts: 8 parts of hexadecyltrimethylammonium bromide, 6 parts of sodium pyrophosphate, 5 parts of zinc stearate, and 120 parts of deionized water; b. Place the mixture obtained in step a into a centrifuge for centrifugal treatment, and then dry the centrifuged material until it is taken out; during the centrifugal treatment, the speed of the centrifuge is controlled to be 5000 rpm; during the drying treatment, the drying temperature is controlled to be 110°C.

[0030] Comparative Example 1 Compared with Example 2, in the preparation of the reinforcing powder, the nano titanium nitride and nano cordierite powder components in step a are omitted in this comparative example 1, and other method steps are the same.

[0031] Comparative Example 2 Compared with Example 2, in this Comparative Example 2, the addition of reinforcing powder is omitted in (3) surface arc spraying treatment, and other method steps are the same.

[0032] Comparative Example 3 Compared with Example 2, this comparative example 3 omits step (3) of surface arc spraying treatment, and other method steps are the same.

[0033] In order to compare the effects of the present invention, the same batch of 430 pressure reducer shell plates were selected as experimental objects, and then surface treatment was performed using the corresponding methods of the above-mentioned embodiment 2, comparative embodiment 1, comparative embodiment 2, and comparative embodiment 3. The composition of the 430 pressure reducer shell plates used is shown in the following Table 1: Table 1

[0034] The specific comparative data of the performance test of the pressure reducer shell plates after each group of treatment are shown in Table 2 below: Table 2

[0035] Note: The stress corrosion resistance duration described in Table 2 above is tested with reference to GB / T17898-1999; the components and contents of the simulated seawater in the simulated seawater immersion are: sodium chloride 28.2 g / L, potassium chloride 0.9 g / L, calcium chloride 1.5 g / L, sodium bicarbonate 0.3 g / L, magnesium chloride 2.3 g / L, magnesium sulfate 3.2 g / L, the balance is water, and the pH value of the simulated seawater is 6.5-7.2, and the temperature is room temperature.

[0036] It can be seen from Table 2 above that the corrosion and weather resistance of the pressure reducer shell after treatment by the present invention has been significantly improved, which effectively extends the service life and stability of the material, and provides a new treatment method for enhancing the quality of the pressure reducer shell material, which is of great value for promotion and application.

[0037] The above description is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the specification, should be within the protection scope of the present invention.

Claims

1. A method for modifying the surface of a pressure reducer housing, characterized in that: The following steps are involved: (1) Surface degreasing and cleaning: Immerse the pressure reducer housing in industrial degreasing agent, soak for 10-15 minutes, then take it out, rinse it with deionized water 2-3 times, and dry it for later use; (2) Surface shot peening: Shot peening is performed on the surface of the pressure reducer housing after the treatment in step (1), and after the treatment is completed, the housing is taken out for use; (3) Surface arc spraying treatment: Perform arc spraying on the surface of the pressure reducer housing after the treatment in step (2), and continue ultrasonic treatment during the process, and take it out for use after completion; (4) Cooling treatment: The pressure reducer housing treated in step (3) is placed in a temperature-variable box for cooling until it cools to room temperature and then taken out.

2. A method for surface modification of a pressure reducer housing according to claim 1, characterized in that: The industrial degreasing agent described in step (1) is acetone; during the immersion treatment, the temperature of the industrial degreasing agent is controlled to be 32-36°C.

3. A method for surface modification of a pressure reducer housing according to claim 1, characterized in that: The blasting medium used in the shot blasting process described in step (2) is corundum sand, and the particle size of the corundum sand is 250 mesh.

4. A method for surface modification of a pressure reducer housing according to claim 1, characterized in that: During the ultrasonic treatment in step (3), the frequency of the ultrasonic wave is controlled to be 600-650 kHz.

5. The method for surface modification of a pressure reducer housing according to claim 1, characterized in that: During the arc spraying treatment in step (3), the current is controlled to be 120-124A, the jet pressure is 0.65-0.75MPa, and the spraying angle is 90°.

6. A method for surface modification of a pressure reducer housing according to claim 1, characterized in that: The spraying powder used in the arc spraying treatment described in step (3) is composed of the following raw materials in corresponding parts by weight: 45-50 parts of nickel-chromium powder, 18-22 parts of ferroboron powder, 4-7 parts of ferrosilicon-zirconium powder, 6-9 parts of aluminum powder, 3-6 parts of magnesium powder, 5-8 parts of ferromanganese powder, and 7-10 parts of reinforcing powder.

7. A method for surface modification of a pressure reducer housing according to claim 6, characterized in that: The preparation method of the reinforcing powder comprises the following steps: a. Mix graphite powder, nano titanium nitride and nano cordierite powder and put them into a ball mill. Then add a modifier into the ball mill. Continue to ball mill for 2-3 hours and then take out the mixture for use. b. Place the mixture obtained in step a into a centrifuge for centrifugal treatment, and then dry the obtained centrifuged material, and then take it out.

8. A method for surface modification of a pressure reducer housing according to claim 7, characterized in that: The graphite powder described in step a is mixed with nano titanium nitride and nano cordierite powder in a corresponding weight ratio of 15-18:2-4:1-3; the amount of the modifier added is 5-7 times the total mass of the graphite powder; the modifier is composed of the following corresponding weight parts: 6-8 parts of hexadecyltrimethylammonium bromide, 3-6 parts of sodium pyrophosphate, 2-5 parts of zinc stearate, and 100-120 parts of deionized water.

9. A method for surface modification of a pressure reducer housing according to claim 7, characterized in that: During the centrifugal treatment in step b, the speed of the centrifuge is controlled to be 4000-5000 rpm; during the drying treatment, the drying temperature is controlled to be 100-110°C.

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