CN115370579A - A slide valve for a compressor, a manufacturing method of the slide valve, and a screw compressor - Google Patents

Abstract

The invention provides a sliding valve for a compressor, a manufacturing method of the sliding valve and a screw compressor, which belong to the technical field of compressors. The valve body of the sliding valve is provided with an arc surface corresponding to the compressor rotor. A composite coating is provided on the arc surface, and when the slide valve is installed on the compressor, the composite coating fills the assembly gap between the slide valve and the compressor rotor. The slide valve reduces the gap between the slide valve and the rotor due to insufficient processing technology by adding a composite coating on the arc surface, and can improve the energy efficiency of the compressor. The manufacturing method of the slide valve includes: after the valve body of the slide valve is prepared, the valve body of the slide valve is pre-treated, the arc surface of the valve body is surface treated, and the arc surface of the slide valve is sprayed once, sintered once, and arc-shaped. After secondary spraying and secondary sintering, the sliding valve with composite coating is obtained.

Description

A slide valve for a compressor, a manufacturing method of the slide valve, and a screw compressor

technical field

The invention relates to the technical field of compressors, in particular to a slide valve for a compressor, a manufacturing method of the slide valve and a screw compressor.

Background technique

The twin-screw compressor has a pair of male and female rotors with helical teeth that mesh with each other and rotate in opposite directions. During operation, the mutual rotation of the male and female rotors is used to pump the gas from the low-pressure end to the high-pressure end. The twin-screw compressor is equipped with a slide valve for the compressor. The slide valve for the compressor is a key component used to adjust the gas delivery in the screw compressor. The slide valve for the compressor has two arc surfaces opposite to the rotor. When the compressor is working, the compressor uses the slide valve to move along the axis of the rotor to change the effective working length of the rotor to achieve the purpose of adjusting the gas delivery.

Due to the shortcomings of the existing compressor processing technology, in order to ensure the safe operation of the compressor, there is a certain design gap between the arc surface of the existing compressor slide valve and the female and male rotors of the compressor. Moreover, in practical applications, due to the existence of assembly errors, the gap between the slide valve of the compressor and the male and female rotors will increase after assembly, and a larger gap will cause the internal leakage of the compressor to increase, reducing the compressor capacity. Volumetric efficiency and energy efficiency.

Therefore, on the premise of ensuring the safe operation of the compressor, how to reduce the cooperation gap between the slide valve for the compressor and the female and male rotors of the compressor has become a problem that needs to be solved urgently in the refrigeration industry.

Contents of the invention

In order to overcome the problems existing in the related art, one of the objects of the present invention is to provide a slide valve for compressors, which can reduce the friction between the slide valve and the rotor due to the processing technology by adding a composite coating on the arc surface. The gap between them can improve the energy efficiency of the compressor.

A slide valve for a compressor, comprising a valve body, the valve body is provided with an arc surface corresponding to the rotor of the compressor, the arc surface is provided with a composite coating, when the slide valve is installed on the compressor , the composite coating fills the assembly gap between the slide valve and the compressor rotor.

In a preferred technical solution of the present invention, the composite coating includes polyetheretherketone and carbon fibers, and the weight percentages of the polyetheretherketone and the carbon fibers in the composite coating are respectively 80% to 80% of polyetheretherketone 90%, carbon fiber 10% to 20%.

In the preferred technical solution of the present invention, the thickness of the composite coating is 85 μm to 110 μm, the composite coating includes a first coating and a second coating, and the first coating is coated on the arc On one side, the second coating is coated on the first coating.

In a preferred technical solution of the present invention, the valve body is provided with a central hole and an air outlet hole, the central hole is arranged at one end of the valve body along the axial direction of the valve body, and the air outlet hole is arranged at The side wall of the valve body communicates with the central hole; the valve body is provided with a relief position, which is arranged at one end of the opening of the central hole, and the cross section of the relief position is L-shaped.

The second object of the present invention is to provide a method for manufacturing a slide valve, which is used for producing the slide valve for a compressor as described above.

In a preferred technical solution of the present invention, the manufacturing method includes the following steps:

A valve body of the slide valve is manufactured, and the valve body is provided with an arc surface corresponding to the rotor of the compressor;

Pre-treatment, removing oil stains and residual impurities on the surface of the valve body;

Carry out surface treatment on the curved surface of the valve body to improve the surface roughness of the curved surface;

Prepare the mixed powder of PEEK and carbon fiber, preheat the valve body, the preheating temperature is 180℃～200℃, and the preheating time is 20min～30min;

Spray the prepared mixed powder of polyether ether ketone and carbon fiber evenly on the curved surface of the valve body to form the first coating; protect the position on the valve body that does not need to be sprayed to avoid the bonding of the mixed powder;

One-time sintering, the valve body that has been sprayed once is transferred to a sintering furnace for high-temperature sintering, so that the first coating is sintered on the arc surface of the valve body; ℃～420℃, and heat preservation at 380℃～420℃ for 0.5h～1.5h, then naturally cool to room temperature, and complete the sintering once;

Secondary spraying, take out the valve body that has been sintered once, and spray the mixed powder evenly on the first coating to form the second coating;

Secondary sintering, transfer the valve body after secondary spraying to a sintering furnace for secondary high-temperature sintering, so that the second coating is sintered on the first coating, and the slide valve is manufactured.

In a preferred technical solution of the present invention, the removal of oil stains and residual impurities on the surface of the valve body includes:

Put the manufactured spool valve body into acetone or petroleum ether, and clean and remove oil in an ultrasonic environment. The cleaning time is 15 minutes to 25 minutes;

Rinse the cleaned valve body with deionized water, blow off the surface impurities with an air gun, and dry it for later use.

In a preferred technical solution of the present invention, the preparation of the mixed powder of polyether ether ketone and carbon fiber includes:

The polyether ether ketone raw material and the carbon fiber raw material are respectively pulverized with a high-speed pulverizer, and sieved to obtain polyether ether ketone powder and carbon fiber powder; the particle size of the polyetheretherketone powder is 15 μm to 25 μm, and the carbon fiber powder The particle size is 15μm～35μm;

Use a ball mill to mix polyether ether ketone powder and carbon fiber powder to mix the two powders evenly to obtain a mixed powder; the ball milling time is 1h to 2h, and the content of polyetheretherketone powder in the mixed powder is controlled to be 80% to 90%. , the content of carbon fiber powder is 10% to 20%;

Dry the mixed powder in a vacuum drying oven at 100°C to 120°C for 10h to 12h, then take it out and grind the mixed powder thoroughly to make the mixed powder evenly dispersed;

The ground mixed powder is placed in a drying oven to dry for 4h-6h at a drying temperature of 50°C-70°C to obtain the mixed powder to be sprayed.

In the preferred technical solution of the present invention, the surface treatment of the arc surface of the valve body to improve the surface roughness of the arc surface includes:

Sand blast the curved surface of the valve body, and clean the sand particles on the surface of the rotor after sand blasting; among them, the sand particles used in the sand blasting process are brown corundum, the particle size is 40 mesh to 60 mesh, and the sand blasting pressure is 0.2MPa to 0.6MPa , the roughness of the arc surface of the valve body after sandblasting requires Rz to be 20 μm to 40 μm;

Immerse the sandblasted valve body in a phosphate solution, so that the phosphate conversion film formed on the arc surface of the valve body is formed.

In the preferred technical solution of the present invention, the surface treatment of the arc surface of the valve body to improve the surface roughness of the arc surface includes:

The arc surface of the slide valve is eroded by plasma gas to improve the surface roughness of the arc surface.

The third object of the present invention is to provide a screw compressor, which includes a male rotor and a female rotor meshing with each other, and the screw compressor is provided with the above-mentioned slide valve.

The beneficial effects of the present invention are:

The invention provides a slide valve for a compressor and a screw compressor. The valve body of the slide valve is provided with an arc surface corresponding to the female rotor and the male rotor of the screw compressor, and a composite coating is provided on the arc surface. The composite coating can fill the assembly gap between the slide valve and the rotor due to insufficient processing technology of the compressor, making the gap between the two smaller, thereby reducing the internal leakage of the screw compressor and improving the energy efficiency and performance of the screw compressor. volumetric efficiency. At the same time, the existence of the composite coating also reduces the machining accuracy requirements of the slide valve, which is beneficial to reduce the manufacturing cost, and the smooth coating is also beneficial to reduce the noise during the operation of the compressor.

The present invention also provides the manufacturing method of the above-mentioned slide valve. After the valve body of the slide valve is prepared, the composite coating is sprayed twice and sintered twice on the arc surface of the slide valve. The combination of the composite coating and the valve body Strong force, the composite coating is not easy to damage, which can prolong the service life of the slide valve.

Description of drawings

1 is a perspective view of a slide valve for a compressor provided in Embodiment 1 of the present invention;

Fig. 2 is the flowchart of the manufacturing method of the slide valve provided in the embodiment 1 of the present invention;

Fig. 3 is the flow chart of the pretreatment process provided in the embodiment 1 of the present invention;

Fig. 4 is a flow chart of the surface treatment process of the arc surface of the valve body provided in Embodiment 1 of the present invention;

Fig. 5 is a flow chart for preparing the mixed powder of polyether ether ketone and carbon fiber provided in Example 1 of the present invention.

Reference signs:

100, valve body; 110, avoidance position; 120, arc surface; 130, center hole; 140, vent hole; 200, composite coating.

Detailed ways

Preferred embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the invention are shown in the drawings, it should be understood that the invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terminology used in the present invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein and in the appended claims, the singular forms "a", "the", and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It should also be understood that the term "and/or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

Example 1:

As shown in FIGS. 1-5 , a slide valve for a compressor includes a valve body 100 , and the valve body 100 is provided with an arc surface 120 corresponding to the rotor of the compressor. A composite coating 200 is provided on the arc surface 120, and when the slide valve is installed on the compressor, the composite coating 200 fills the assembly gap between the slide valve and the rotor of the compressor.

Due to the limitation of the production process, in order to ensure the safe operation of the screw compressor, there is a certain gap on the mating surface between the slide valve and the female rotor and male rotor of the screw compressor. This gap is difficult to completely eliminate by improving the assembly process of the compressor. Therefore, this application increases the composite coating 200 on the arc surface 120 corresponding to the slide valve, the female rotor and the male rotor, and the filling of the composite coating 200 reduces the assembly gap between the slide valve and the female rotor and the male rotor, reducing the Leakage in compressor. It should be noted that the surface of the composite coating 200 is smooth and the thickness is uniform, so as to prevent the composite coating 200 from affecting the normal rotation of the female rotor and the male rotor.

In a more specific embodiment, the composite coating 200 includes polyetheretherketone and carbon fibers, and the weight percentages of the polyetheretherketone and the carbon fibers in the composite coating 200 are respectively 80% of polyetheretherketone %~90%, carbon fiber 10%~20%. More specifically, the composite coating 200 has a thickness of 85 μm to 110 μm, the composite coating 200 includes a first coating and a second coating, the first coating is coated on the curved surface 120, The second coating is coated on the first coating.

Carbon fiber belongs to the structure of turbostratic graphite, which has the characteristics of ordinary graphite, and has the soft, programmable and self-lubricating properties of general limits. Carbon fiber has high strength, high stiffness, good corrosion resistance and thermal stability. Combining carbon fiber and polyether ether ketone can significantly improve the friction and wear performance of composite coating 200, and ensure that composite coating 200 can fill slide valves and rotors. The gap between them will not affect the rotor operation. During the operation of the rotor, the rotor friction composite coating 200, the graphite in the carbon fiber will be converted into a transfer film, which acts as a lubricant and can reduce the friction between the rotor and the slide valve, thereby reducing the obstruction and friction during operation. noise.

The above-mentioned slide valve and screw compressor for a compressor, the valve body 100 of the slide valve is provided with an arc surface 120 corresponding to the female rotor and the male rotor of the screw compressor, and the arc surface 120 is provided with a composite coating 200. The composite coating 200 can fill the assembly gap between the slide valve and the rotor due to insufficient technology, and make the gap between the two smaller, thereby reducing the internal leakage of the screw compressor and improving the energy efficiency and volumetric efficiency of the screw compressor .

In a specific embodiment, the valve body 100 is provided with a central hole 130 and an air outlet hole 140, and the central hole 130 is arranged at one end of the valve body 100 along the axial direction of the valve body 100, so The air outlet hole is arranged on the side wall of the valve body 100 and communicates with the central hole 130; the valve body 100 is provided with an escape position 110, and the escape position 110 is arranged at one end of the opening of the central hole 130, The cross-section of the avoidance position 110 is L-shaped.

The central hole 130 is convenient for the slide valve to be installed in the slide valve cavity of the compressor, and the air outlet hole 140 is used to discharge the gas in the compression cavity of the compressor. The slide valve cooperates with the slide valve cavity of the compressor through the avoidance position 110, so as to avoid mutual interference between various components and ensure the normal operation of the compressor.

The present invention also provides a method for manufacturing a slide valve, which is used for producing the slide valve for a compressor as described above.

In this method, after the valve body 100 of the slide valve is prepared, the composite coating 200 is sprayed twice and sintered twice on the arc surface 120 of the slide valve. The combination of the composite coating 200 and the valve body 100 is strong, and the composite coating 200 is not easy to damage and can prolong the service life of the slide valve.

In the composite coating 200 of the slide valve in this embodiment, the weight percentages of PEEK and carbon fiber are 80% and 20% respectively.

The manufacturing method of described slide valve comprises the following steps:

S100. Manufacture the valve body 100 of the slide valve, and the valve body 100 is provided with an arc surface 120 corresponding to the compressor rotor; specifically, the manufacturing process of the valve body 100 of the slide valve can be produced by machining. It should be noted that the machined valve body 100 not only has an arc surface 120 corresponding to the rotor, but also has features such as a center hole 130 , an air outlet hole 140 , and a relief position 110 .

S200 , pretreatment, removing oil stains and residual impurities on the surface of the valve body 100 .

Specifically, the specific process of pre-processing includes:

S210, put the manufactured slide valve body 100 into acetone or petroleum ether, and clean and remove oil in an ultrasonic environment, and the cleaning time is 15 minutes to 25 minutes;

S220. Rinse the cleaned valve body 100 with deionized water, blow off surface impurities with an air gun, and dry for later use.

In practical applications, in addition to using acetone or petroleum ether to clean and remove oil, you can also use any one of anhydrous ethanol to remove oil, detergent to remove oil, alkali to remove oil, high temperature to remove oil, ultrasonic cleaning to remove oil or The combination of two or more cleans the valve body 100 . During the ultrasonic cleaning process, the cleaning time needs to be ensured so as to completely remove the oil stain on the valve body 100 .

S300, performing surface treatment on the arc surface 120 of the valve body 100 to improve the surface roughness of the arc surface 120;

More specifically, the process of surface treatment of the valve body 100 includes:

S310. Sand blast the curved surface 120 of the valve body 100. After sand blasting, clean the sand particles on the surface of the rotor; the sand particles used in the sand blasting process are brown corundum with a particle size of 40 mesh to 60 mesh, and the sand blasting pressure is 0.2 MPa ~ 0.6MPa, the roughness of the arc surface 120 of the valve body 100 after sandblasting requires Rz to be 20μm~40μm;

S320 , immersing the sandblasted valve body 100 in a phosphate solution, so that the phosphate conversion film formed on the arc surface 120 of the valve body 100 is formed. It should be noted that for parts that do not require sandblasting, immersion in phosphate solution needs to be protected, such as wrapping and covering with adhesive tape.

The sandblasting process is carried out by a sandblasting machine, which can remove impurities such as oxide scales and carbides on the arc surface 120 of the slide valve. In practical application, after sandblasting, the surface cleanliness Sa of the treated surface needs to reach level 2.5 or above. The distance between the nozzle of the spray gun of the sandblasting machine and the arc surface 120 of the slide valve is about 2 cm to 4 cm, and the spray angle is about 65° to 85°. Before sandblasting, it is necessary to protect the parts that do not need sandblasting. It can be covered with tape or tin foil to prevent spraying to other non-blasting areas. After sandblasting, use an air gun to blow off the remaining sand particles on the surface.

S400, preparing mixed powder of polyetheretherketone and carbon fiber, and preheating the valve body 100, the preheating temperature is 180°C-200°C, and the preheating time is 20min-30min. During the process of preparing the mixed powder, the valve body 100 is preheated at the same time, so as to save production time. By preheating the valve body 100 in advance, the temperature difference between the polyether ether ketone composite coating 200 and the valve body 100 can be reduced, which is conducive to improving the bonding strength between the composite coating 200 and the valve body 100, making the composite coating 200 difficult to produce. Cracks, microporous defects, and reduced roughness of the composite coating 200. At the same time, the moisture on the surface of the valve body 100 can be removed and the surface can be activated to facilitate the combination of the composite coating 200 and the valve body 100 and control the expansion of the valve body 100 relative to the composite coating 200 .

S500, one spraying, evenly spray the prepared mixed powder of polyether ether ketone and carbon fiber on the arc surface 120 of the valve body 100 to form the first coating; protect the position on the valve body 100 that does not need to be sprayed to avoid mixing Bonding of powder: In this embodiment, the weight percentages of polyetheretherketone and carbon fiber mixed powder in the composite powder are 80% and 20% respectively. The spraying process can adopt the electrostatic spraying method, wherein the electrostatic spraying voltage: 40kV ~ 80kV, spraying current: 10μA ~ 30μA, powder output 30% ~ 50%, powder supply pressure 0.2Mpa ~ 0.6Mpa. Before spraying, it is necessary to protect the position that does not need to be sprayed. When spraying, try to ensure that the spraying is even. In practical applications, manual spraying mixed powder emulsion, plasma spraying, thermal spraying, supersonic flame spraying, brushing, cold pressing sintering, electrophoresis and other methods can be used instead of electrostatic spraying.

S600, one-time sintering, transfer the valve body 100 that has been sprayed once to a sintering furnace for high-temperature sintering, so that the first coating is sintered on the arc surface 120 of the valve body 100; the sintering process is: the temperature of the sintering furnace is changed from room temperature to 20 minutes Rise to 380°C-420°C in ~25 minutes, and hold at 380°C-420°C for 0.5h-1.5h, then cool down to room temperature naturally, and the primary sintering is completed.

S700, secondary spraying, take out the valve body 100 that has been sintered once, and evenly spray the mixed powder on the first coating to form a second coating; the process used for the secondary spraying can be the same as that of the primary spraying .

S800, secondary sintering, transfer the valve body 100 that has been sprayed for the second time to a sintering furnace for secondary high-temperature sintering, so that the second coating is sintered on the first coating, and the manufacture of the slide valve is completed.

In another embodiment, the slide valve can be quenched after the secondary sintering, so that the composite coating 200 is cooled rapidly, the surface of the quenched composite coating 200 is smoother, and the friction force of the rotor is smaller when the rotor moves.

In this application, the composite coating formed on the cambered surface of the slide valve by two times of spraying and two times of sintering has a stable structure and is not easy to fall off. During electrostatic spraying, a high-voltage corona discharge electric field is formed between the spray gun and the workpiece. When the powder particles are sprayed from the spray gun mouth and pass through the discharge area, a large number of electrons are collected and become negatively charged particles. Next, it is adsorbed to the positively charged workpiece. The maximum thickness of the composite coating formed by spraying at one time is about 80 μm, and the adhesion of the composite coating exceeding this spraying thickness is reduced, and the thickness of each part of the coating is uneven. The composite coating of the present application is formed by spraying twice, so that the second coating can be adhered and fused with the first coating, which not only ensures uniform thickness of the prepared coating, but also has strong adhesion and is not easy to fall off, which can meet the requirements of the slide valve. Long-term use needs.

After the composite coating 200 is manufactured, an adhesion strength test is required: the adhesion between the composite coating 200 and the valve body 100 is measured according to the requirements and procedures of ASTM D4541, and the pulling force test is carried out by a pulling method. The pulling force of the composite coating of the present application can reach more than 12Mpa.

Do the thermal shock test on the composite coating on the slide valve of the application: according to the regulations in GB/T5170.10, after 10 cycles of high temperature and low temperature at 70°C, 95% humidity, and -40°C , The paint film is complete, without cracking, warping, peeling and other phenomena.

Do the oil and fluorine resistance test on the composite coating on the slide valve of this application: process the sample to be tested into a sample with a thickness of 100mm*10mm*2mm and a coating thickness of 75μm-150μm, and put it into the refrigerating machine oil to be tested after processing , Put the glass tube containing the refrigerating machine oil and the test sample into the autoclave, tighten the lid of the autoclave to seal, and use a vacuum pump to evacuate the autoclave for 20 minutes. Then carry out the oil and fluorine resistance test with a test temperature of 172°C to 175°C, a test pressure of 4.2±0.3MPa, and a test time of 168 hours. The coating has no discoloration, foaming and cracking. The paint is scraped with a 2H pencil, and the paint film does not fall off. ; There is no sediment in the refrigerating machine oil, and the pH test paper is not acidic.

The energy efficiency test of the screw compressor adopting the sliding valve of the present application is carried out: the sliding valve is operated for more than 120,000 hours under normal operating conditions, the energy efficiency of the screw compressor is tested, and the energy efficiency of the compressor is increased by 2% to 4%. Moreover, the composite coating did not fall off after 120,000 hours of use on the slide valve.

In a specific embodiment, the preparation of the mixed powder of polyether ether ketone and carbon fiber includes:

S410. Grinding polyetheretherketone raw materials and carbon fiber raw materials with a high-speed pulverizer respectively, and sieving to obtain polyetheretherketone powder and carbon fiber powder; the particle size of the polyetheretherketone powder is 15 μm to 25 μm, and the carbon fiber The particle size of powder is 15μm～35μm;

S420. Use a ball mill to mix polyether ether ketone powder and carbon fiber powder, so that the two powders are evenly mixed to obtain a mixed powder; the ball milling time is 1h to 2h, and the content of the polyether ether ketone powder in the mixed powder is controlled to be 80% to 80%. 90%, the content of carbon fiber powder is 10% to 20%;

S430. The mixed powder is dried in a vacuum drying oven at 100° C. to 120° C. for 10 hours to 12 hours, and then the mixed powder is taken out and fully ground to make the mixed powder evenly dispersed; the grinding process is carried out with a mortar.

S440. Put the ground mixed powder in a drying oven to dry for 4 hours to 6 hours at a drying temperature of 50° C. to 70° C. to obtain a mixed powder to be sprayed. What needs to be said is that in the mixed powder to be used for spraying, the weight percentages of polyetheretherketone powder and carbon fiber powder are formulated according to a set ratio.

The present invention also provides a screw compressor, which includes a male rotor and a female rotor that mesh with each other, and the screw compressor is provided with the above-mentioned slide valve. The compressor has small internal leakage and high energy efficiency.

Example 2:

In the composite coating 200 of the slide valve in this embodiment, the weight percentages of PEEK and carbon fiber are 90% and 10% respectively.

The manufacturing method of described slide valve comprises the following steps:

S100. Manufacture the valve body 100 of the slide valve, and the valve body 100 is provided with an arc surface 120 corresponding to the rotor of the compressor; specifically, the manufacturing process of the valve body 100 of the slide valve can be produced by machining. It should be noted that the machined valve body 100 not only has an arc surface 120 corresponding to the rotor, but also has features such as a center hole 130 , an air outlet hole 140 , and a relief position 110 .

S200 , pretreatment, removing oil stains and residual impurities on the surface of the valve body 100 .

S300, performing surface treatment on the arc surface 120 of the valve body 100 to improve the surface roughness of the arc surface 120;

More specifically, the process of surface treatment of the valve body 100 includes:

S310. Sand blast the curved surface 120 of the valve body 100. After sand blasting, clean the sand particles on the surface of the rotor; the sand particles used in the sand blasting process are brown corundum with a particle size of 40 mesh to 60 mesh, and the sand blasting pressure is 0.2 MPa ~ 0.6MPa, the roughness of the arc surface 120 of the valve body 100 after sandblasting requires Rz to be 20μm~40μm;

S320 , immersing the sandblasted valve body 100 in a phosphate solution, so that the phosphate conversion film formed on the arc surface 120 of the valve body 100 is formed.

The sandblasting process is carried out by a sandblasting machine, which can remove impurities such as oxide scales and carbides on the arc surface 120 of the slide valve. In practical application, after sandblasting, the surface cleanliness Sa of the treated surface needs to reach level 2.5 or above. The distance between the nozzle of the spray gun of the sandblasting machine and the arc surface 120 of the slide valve is about 2 cm to 4 cm, and the spray angle is about 65° to 85°. Before sandblasting, it is necessary to protect the parts that do not need sandblasting. It can be covered with tape or tin foil to prevent spraying to other non-blasting areas. After sandblasting, use an air gun to blow off the remaining sand particles on the surface.

S400, preparing mixed powder of polyetheretherketone and carbon fiber, and preheating the valve body 100, the preheating temperature is 180°C-200°C, and the preheating time is 20min-30min. During the process of preparing the mixed powder, the valve body 100 is preheated at the same time, so as to save production time. By preheating the valve body 100 in advance, the temperature difference between the polyether ether ketone composite coating 200 and the valve body 100 can be reduced, which is conducive to improving the bonding strength between the composite coating 200 and the valve body 100, making the composite coating 200 difficult to produce. Cracks, microporous defects, and reduced roughness of the composite coating 200. At the same time, the moisture on the surface of the valve body 100 can be removed and the surface can be activated to facilitate the combination of the composite coating 200 and the valve body 100 and control the expansion of the valve body 100 relative to the composite coating 200 .

S500, one spraying, evenly spray the prepared mixed powder of polyether ether ketone and carbon fiber on the arc surface 120 of the valve body 100 to form the first coating; protect the position on the valve body 100 that does not need to be sprayed to avoid mixing Bonding of powder: In this embodiment, the weight percentages of polyetheretherketone and carbon fiber mixed powder in the composite powder are 90% and 10% respectively. The spraying process can adopt the electrostatic spraying method, wherein the electrostatic spraying voltage: 40kV ~ 80kV, spraying current: 10μA ~ 30μA, powder output 30% ~ 50%, powder supply pressure 0.2Mpa ~ 0.6Mpa. Before spraying, it is necessary to protect the position that does not need to be sprayed. When spraying, try to ensure that the spraying is even.

S600, one-time sintering, transfer the valve body 100 that has been sprayed once to a sintering furnace for high-temperature sintering, so that the first coating is sintered on the arc surface 120 of the valve body 100; the sintering process is: the temperature of the sintering furnace is changed from room temperature to 20 minutes Rise to 380°C-420°C in ~25 minutes, keep warm at 380°C-420°C for 0.5h-1.5h, then cool down to room temperature naturally, and complete the sintering once;

S700, secondary spraying, take out the valve body 100 that has been sintered once, and evenly spray the mixed powder on the first coating to form a second coating; the process used for the secondary spraying can be the same as that of the primary spraying .

S800, secondary sintering, transfer the valve body 100 that has been sprayed for the second time to a sintering furnace for secondary high-temperature sintering, so that the second coating is sintered on the first coating, and the manufacture of the slide valve is completed. Example 3:

This embodiment only describes the differences from Embodiment 1, and the rest of the technical features are the same as those of the above embodiment.

Example 3:

In this embodiment, the surface treatment of the arc surface 120 of the valve body 100 to improve the surface roughness of the arc surface 120 includes:

The arc surface 120 of the slide valve is eroded by plasma gas to increase the surface roughness of the arc surface 120 .

Plasma is an ionized gas that can be excited by electromagnetic waves in a closed reactor system containing a low-pressure gas mixture. When using plasma to process the arc surface 120, the electrons and ions in the ion body hit the arc surface 120 of the valve body 100 to cause sputter erosion, or the chemically active substances in the plasma impact on the arc surface 120 of the valve body 100. chemical attack. When the plasma sputtering erodes the surface of the material, due to the different erosion rates of the arc surface 120 of the valve body 100, the surface of the material will produce fine unevenness; the sputtered material will be excited and decomposed into gaseous components in the plasma, Diffusion to the surface of the material. Therefore, a large number of protrusions are formed on the arc surface 120 during erosion and re-aggregation, so that the arc surface 120 of the valve body 100 is roughened, and the contact area between the composite coating 200 and the arc surface 120 of the valve body 100 is increased, thereby Improve the adhesion of the composite coating 200.

The relative arrangements of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise. At the same time, it should be understood that, for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered part of the Authorized Specification. In all examples shown and discussed herein, any specific values should be construed as illustrative only, and not as limiting. Therefore, other examples of the exemplary embodiment may have different values. It should be noted that like numerals and letters denote like items in the following figures, therefore, once an item is defined in one figure, it does not require further discussion in subsequent figures. In the description of the present application, it should be understood that orientation words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" etc. indicate the orientation Or positional relationship is generally based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description. In the absence of a contrary statement, these orientation words do not indicate or imply the device or element referred to It must have a specific orientation or be constructed and operated in a specific orientation, so it should not be construed as limiting the protection scope of the present application; the orientation words "inner and outer" refer to the inner and outer relative to the outline of each component itself.

For the convenience of description, spatially relative terms may be used here, such as "on ...", "over ...", "on the surface of ...", "above", etc., to describe the The spatial positional relationship between one device or feature shown and other devices or features. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, devices described as "above" or "above" other devices or configurations would then be oriented "beneath" or "above" the other devices or configurations. under other devices or configurations". Thus, the exemplary term "above" can encompass both an orientation of "above" and "beneath". The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptions used herein interpreted accordingly.

In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing corresponding components. To limit the protection scope of this application. The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (11)

1. The utility model provides a slide valve for compressor, includes the valve body, be equipped with the cambered surface corresponding with the compressor rotor on the valve body, its characterized in that: and the cambered surface is provided with a composite coating, and when the slide valve is installed on the compressor, the composite coating fills an assembly gap between the slide valve and a rotor of the compressor.

2. The sliding valve for a compressor according to claim 1, wherein:

the composite coating comprises 80-90 wt% of polyether-ether-ketone and 10-20 wt% of carbon fiber.

3. The sliding valve for a compressor according to claim 2, wherein:

the thickness of the composite coating is 85-110 microns, the composite coating comprises a first coating and a second coating, the first coating is coated on the cambered surface, and the second coating is coated on the first coating.

4. A sliding valve for a compressor according to any one of claims 1 to 3, wherein:

the valve body is internally provided with a central hole and an air outlet hole, the central hole is arranged at one end of the valve body along the axial direction of the valve body, and the air outlet hole is arranged on the side wall of the valve body and communicated with the central hole; the valve body is provided with an avoiding position, the avoiding position is arranged at one end of the opening of the central hole, and the cross section of the avoiding position is L-shaped.

5. A method of manufacturing a spool valve, characterized by: the manufacturing method is used for producing a slide valve for a compressor according to any one of claims 1 to 4.

6. A method of manufacturing a slide valve according to claim 5, comprising the steps of:

manufacturing a valve body of the slide valve, wherein the valve body is provided with a cambered surface corresponding to a compressor rotor;

pre-treating, namely removing oil stains and residual impurities on the surface of the valve body;

carrying out surface treatment on the cambered surface of the valve body to improve the surface roughness of the cambered surface;

preparing mixed powder of polyether-ether-ketone and carbon fiber, and preheating the valve body at 180-200 ℃ for 20-30 min;

spraying the prepared mixed powder of the polyether-ether-ketone and the carbon fiber on the cambered surface of the valve body uniformly to form a first coating; the position on the valve body which does not need spraying is protected, and the bonding of mixed powder is avoided;

primary sintering, namely transferring the valve body subjected to primary spraying to a sintering furnace for high-temperature sintering to enable the first coating to be sintered on the cambered surface of the valve body; the sintering process is as follows: raising the temperature of the sintering furnace from room temperature to 380-420 ℃ after 20-25 min, preserving the temperature at 380-420 ℃ for 0.5-1.5 h, naturally cooling to room temperature, and completing one-time sintering;

secondary spraying, namely taking out the valve body which is sintered once, and uniformly spraying the mixed powder on the first coating to form a second coating;

and (4) secondary sintering, namely transferring the valve body subjected to secondary spraying to a sintering furnace for secondary high-temperature sintering, so that the second coating is sintered on the first coating, and the slide valve is manufactured.

7. The method for manufacturing a spool according to claim 6, wherein:

the greasy dirt and the residual impurity of detaching the valve body surface include:

putting the manufactured slide valve body into acetone or petroleum ether, and cleaning and deoiling in an ultrasonic environment for 15-25 min;

and washing the cleaned valve body with deionized water, blowing away surface impurities with an air gun, and drying for later use.

8. The method of manufacturing a spool valve according to claim 6, characterized in that:

the mixed powder for preparing the polyetheretherketone and the carbon fiber comprises the following components:

respectively crushing a polyether-ether-ketone raw material and a carbon fiber raw material by using a high-speed crusher, and sieving to obtain polyether-ether-ketone powder and carbon fiber powder; the particle size of the polyether-ether-ketone powder is 15-25 mu m, and the particle size of the carbon fiber powder is 15-35 mu m;

mixing polyether-ether-ketone powder and carbon fiber powder by using a ball mill, and uniformly mixing the two kinds of powder to prepare mixed powder; wherein, the ball milling time is 1-2 h, the content of the polyetheretherketone powder in the mixed powder is controlled to be 80-90%, and the content of the carbon fiber powder is controlled to be 10-20%;

drying the mixed powder in a vacuum drying oven at 100-120 ℃ for 10-12 h, taking out the powder, and fully grinding the powder to uniformly disperse the powder;

and (3) drying the ground mixed powder in a drying oven for 4-6 h at the drying temperature of 50-70 ℃ to obtain the mixed powder to be sprayed.

9. The method of manufacturing a spool valve according to claim 6, characterized in that:

carry out surface treatment to the cambered surface of valve body, improve the surface roughness of cambered surface, include:

carrying out sand blasting on the cambered surface of the valve body, and cleaning sand grains on the surface of the rotor after the sand blasting; wherein, the sand used in the sand blasting process is brown corundum, the grain diameter is 40-60 meshes, the sand blasting pressure is 0.2-0.6 MPa, and the roughness of the cambered surface of the valve body after sand blasting requires Rz to be 20-40 mu m;

and (3) immersing the valve body subjected to sand blasting into phosphate solution to form a phosphate conversion film on the cambered surface of the valve body.

10. The method of manufacturing a spool valve according to claim 6, characterized in that:

carry out surface treatment to the cambered surface of valve body, improve the surface roughness of cambered surface, include:

the arc surface of the slide valve is eroded by plasma gas, and the surface roughness of the arc surface is improved.

11. A screw compressor comprising intermeshing male and female rotors, characterized in that: the screw compressor is provided with a slide valve according to any one of claims 1 to 4.

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