Aviation gear part cleanliness control method

Abstract

The invention belongs to the field of machining, and discloses an aviation gear part cleanliness control method, which comprehensively identifies and classifies cleanliness risk points in the whole machining process, and divides the cleanliness risk points into risk points of three key stages of pretreatment, intermediate treatment and packaging. In the pretreatment stage, initial pollution is effectively removed through polishing and oil stain particle cleaning; in the intermediate treatment stage, ultrasonic cleaning is combined with finishing machining to deeply clean and protect the surfaces of the parts, and meanwhile, a part box protective tool is adopted to ensure that secondary pollution in the turnover process is minimized; before packaging, the final cleanliness is ensured through demagnetization, residual magnetism inspection and a three-step cleaning method, and the grade is strictly evaluated. According to the method, the automation degree and the cleaning efficiency are greatly improved, the cleaning effect is remarkably improved, the cleaning cost is reduced, whole-process cleanliness control from part machining to packaging is achieved, and it is ensured that the cleanliness of aviation gear parts meets the strict requirement of the aviation field.

Description

Technical Field

[0001] The invention belongs to the field of mechanical processing, specifically to the field of cleanliness control of aviation parts, and in particular to a method for controlling the cleanliness of aviation gear parts. Background Art

[0002] Cleaning is a very important part of modern manufacturing production, and effective cleaning is one of the key factors to ensure the final quality of the product. Cleanliness is an indicator used to characterize the cleanliness level of parts and components, and is also the limit value of residual particulate contaminants on the surface of parts and components after cleaning, involving the type, size, quantity and quality of particulate contaminants. With the rapid improvement of the technological level of modern manufacturing, cleaning technology has received more and more attention and is widely used in many industries such as aerospace, vehicles, and medical equipment. In the aviation field, specifically in the field of many parts of aircraft engines, cleanliness has a more obvious impact on the life of fuel and lubricating oil systems such as bearings, pumps, valves, gears, and moving parts. The life of parts with uncontrolled cleanliness and controlled cleanliness can differ by several times or even dozens of times. At the same time, it can also have a greater impact on the processing accuracy and performance of parts and components, which to a certain extent affects the quality of the entire aircraft engine product.

[0003] At present, the cleaning process for hydraulic, fuel and lubrication systems on aircraft mostly uses manual or semi-automated immersion ultrasonic cleaning, which has problems such as low automation, poor cleaning effect, low efficiency and high cleaning cost, and the cleaning quality is difficult to meet higher cleanliness standards. More importantly, the traditional cleanliness control process only stays in the cleaning process of parts and cleanliness detection at individual links, and cannot achieve cleanliness control in the entire process, resulting in uncontrolled cleanliness of parts and components, and cannot meet the cleanliness level requirements of aviation parts.

[0004] It can be seen that the existing cleanliness control method is limited to the parts cleaning process and cleanliness inspection in individual links, and cannot achieve cleanliness control in the entire process, resulting in uncontrolled cleanliness of parts. Summary of the invention

[0005] The purpose of the present invention is to provide a method for controlling the cleanliness of aviation gear parts to solve the technical problem that the existing cleanliness control method is limited to the cleaning process of parts and the cleanliness detection in individual links, and cannot achieve cleanliness control in the whole process, resulting in uncontrolled cleanliness of parts.

[0006] In order to achieve the above object, the present invention adopts the following technical solution: A method for controlling the cleanliness of aviation gear parts, comprising: Obtain the cleanliness risk points of aviation gear parts during the entire processing process; Divide all cleanliness risk points into pre-processing risk points, intermediate processing risk points, and pre-packaging risk points; Aiming at the pre-treatment risk points, aviation gear parts are processed by grinding and oil particle cleaning in turn; Aiming at the intermediate processing risk points, ultrasonic cleaning and finishing processing are used to process aviation gear parts in turn; in the turnover process of aviation gear parts, parts boxes and protective gears are used to protect aviation gear parts; In view of the risk points before packaging, the aviation gear parts are processed in sequence by demagnetization, residual magnetism inspection and three-step cleaning method, and the cleanliness level of the aviation gear parts is evaluated after cleaning.

[0007] Furthermore, the cleanliness risk points include the following categories: Category 1: During the machining of aviation gear parts, burrs are generated by turning, grinding, hobbing and grinding, and the burrs are not completely removed, resulting in the risk of residual burrs; Category 2: Particles adhere to the surface of aviation gear parts before heat treatment, and tiny particles are coated during the heat treatment process, which poses a risk of falling off later; Category 3: During magnetic flaw detection, there is a risk of foreign matter being introduced into the magnetic flaw detection fluid; Category 4: Before processing inspection, there is a risk of foreign matter and fiber residue on aviation gear parts; Category 5: There is a risk of environmental pollution during the turnover and packaging of aviation gear parts; Category 6: There is residual magnetism in the processing of aviation gear parts, and there is a risk of residual metal foam adhesion; Category 7: Improper arrangement of the cleaning process leads to the risk of incomplete cleaning.

[0008] Furthermore, cleanliness risk points also include: Category 8: During the packaging process, there are problems with aviation gear parts being bumped into.

[0009] Further, After the cleanliness level evaluation is completed, aviation gear parts are packaged using gas phase packaging.

[0010] Furthermore, in view of the pre-treatment risk points, the specific steps for treating aviation gear parts by grinding and cleaning oil particles are as follows: Grinding wheels and files are used to remove burrs along the top circle and end face of the teeth of aviation gear parts. The tooth profile is rounded to R0.2max, and the rest of the parts are rounded to R0.3max. At the same time, felt wheel polishing is added to remove residual burrs at the tooth profile transition. After grinding, the residual burrs of aviation gear parts are detected using a stereo microscope; The oil particle removal method adopts a soaking, rinsing and compressed air drying process to remove oil and metal particles attached to the surface of aviation gear parts before heat treatment, and to clean aviation gear parts before and after magnetic detection to remove residual liquid; After cleaning with oil particles, the surface of aviation gear parts is visually inspected.

[0011] Furthermore, in view of the intermediate processing risk points, the specific steps of using ultrasonic cleaning and finishing processing to process aviation gear parts are as follows: The process of soaking and rinsing, single tank ultrasonic cleaning and compressed air drying is used to remove foreign matter and fiber residue from aviation gear parts before processing and testing. After the removal of foreign matter and fiber residues, the surface of aviation gear parts is visually inspected for foreign matter and fiber residues.

[0012] Furthermore, the specific process of the single tank ultrasonic cleaning includes: Mix the water-based cleaning agent and deionized water and place it in a single tank ultrasonic cleaning machine; Set the single tank ultrasonic cleaning machine to a cleaning frequency of 40-45KHz, a cleaning time of 3-5min, and a heating temperature of 40-55°C; Place the aviation gear parts into the single-tank ultrasonic cleaning machine to complete the single-tank ultrasonic cleaning; After the aircraft gear parts are finished, the parts are finished by finishing to reduce burrs and metal chips.

[0013] Furthermore, in view of the risk points before packaging, the demagnetization, residual magnetism inspection and three-step cleaning methods are used to treat the aviation gear parts in sequence, and the specific steps for evaluating the cleanliness level of aviation gear parts after cleaning are as follows: Demagnetize aviation gear parts, and after demagnetization, use a magnetometer to check residual magnetism. The qualified standard for residual magnetism inspection is: the residual magnetism value is less than or equal to 3GS; The three-step cleaning method is used to treat aviation gear parts. The specific steps are: After the residual magnetism inspection, the aviation gear parts are subjected to pre-cleaning, through-type cleaning and composite cleaning in sequence; wherein the ultrasonic frequencies corresponding to the pre-cleaning, through-type cleaning and composite cleaning are successively reduced to remove residual particles of different sizes; The cleanliness level of cleaned aviation gear parts is tested to achieve cleanliness level assessment.

[0014] Furthermore, the specific steps of sequentially performing pre-cleaning, through-cleaning and composite cleaning on the aviation gear parts after the residual magnetism inspection are as follows: Use single-slot ultrasonic waves with an ultrasonic frequency of 40 to 45 kHz to pre-clean aviation gear parts after residual magnetism inspection; Use multi-slot ultrasonic waves with an ultrasonic frequency of 28 to 35 KHz to clean aviation gear parts; The aviation gear parts are cleaned by vacuum low-frequency ultrasonic rough cleaning with an ultrasonic frequency of 20 to 25 KHz, vacuum low-frequency ultrasonic fine cleaning and high vacuum drying.

[0015] Furthermore, the multi-slot ultrasonic wave adopts a six-slot ultrasonic wave, and the filtering accuracy of the six slots ranges from 50um to 5um.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a method for controlling the cleanliness of aviation gear parts. The method comprehensively identifies and classifies the cleanliness risk points in the entire processing process, and divides the risk points into three key stages: pretreatment, intermediate processing, and pre-packaging. At the same time, targeted treatment measures are taken: in the pretreatment stage, initial contamination is effectively removed by grinding and cleaning of oil particles; in the intermediate processing stage, ultrasonic cleaning combined with finishing processing is used to deeply clean and protect the surface of parts, and at the same time, parts box protectors are used to ensure that secondary contamination during the turnover process is minimized; before packaging, demagnetization, residual magnetism inspection and three-step cleaning method are used to ensure the final cleanliness, and the level is strictly evaluated. The use of this method not only greatly improves the degree of automation and cleaning efficiency, significantly improves the cleaning effect, reduces the cleaning cost, realizes the cleanliness control of the entire process from part processing to packaging, and ensures that the cleanliness of aviation gear parts meets the strict requirements of the aviation field, thereby solving the problems of insufficient automation, poor cleaning effect, low efficiency and uncontrolled cleanliness in traditional cleanliness control methods.

[0017] Preferably, in the present invention, a variety of cleanliness risk point categories are provided, which provide clear guidance for subsequent cleaning measures. This classification and identification method helps to fully understand and grasp the difficulties and key points of cleanliness control, thereby formulating more effective cleaning strategies.

[0018] Preferably, in the present invention, the collision problem during the packaging process enriches the cleanliness risk point category, which helps to avoid secondary contamination and damage to parts during the packaging stage, and improves the overall quality and reliability of the product.

[0019] Further preferably, in the present invention, the gas phase packaging method is adopted, which can effectively prevent aviation gear parts from being contaminated during storage and transportation, maintain the cleanliness and performance stability of the parts, and extend the service life of the product.

[0020] Preferably, in the present invention, specific grinding and oil particle cleaning steps are proposed for pre-treatment risk points. These steps can completely remove burrs and oil particles on the surface of parts, provide a good foundation for subsequent processing and cleaning, and ensure the cleanliness and processing quality of parts.

[0021] Preferably, in the present invention, in the intermediate processing stage, foreign matter and fiber residues on the surface of parts are effectively removed by combining ultrasonic cleaning and visual inspection, thereby improving the cleanliness and surface quality of parts and providing guarantees for subsequent processing and assembly.

[0022] Preferably, in the present invention, the specific process of single-tank ultrasonic cleaning includes the selection of cleaning agents, the setting of cleaning frequency, time and temperature, and the method of finishing. These measures can further improve the cleanliness and surface quality of parts and meet the high standards for parts in the aviation field.

[0023] Preferably, in the present invention, in the pre-packaging stage, the magnetic material and residual particles on the parts are completely removed through demagnetization, residual magnetism inspection and a three-step cleaning method, thereby ensuring the cleanliness and non-magnetism of the parts and meeting the special requirements of the aviation field for parts.

[0024] Further preferably, in the present invention, the specific steps of the three-step cleaning method and the selection of ultrasonic frequencies can effectively remove residual particles of different sizes, improve the efficiency and effect of cleaning, and ensure that the cleanliness level of parts meets aviation standards; at the same time, the use of oscillations with different ultrasonic frequencies greatly improves the cleaning effect.

[0025] More preferably, in the present invention, six-slot ultrasonic wave is used for through-type cleaning, and the filtering accuracy of each slot is different, so that particles of different sizes can be gradually removed, the fineness and efficiency of cleaning are improved, and the cleanliness and surface quality of parts are ensured; at the same time, the use of six-slot ultrasonic wave also improves the automation and stability of cleaning, and reduces the difficulty and cost of manual operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of cleanliness risk points during the entire processing of aviation gear parts provided by an embodiment of the present invention; Figure 2 A tooth profile diagram of an aviation gear component under a stereo microscope provided by an embodiment of the present invention; Figure 3 A flow chart of a method for controlling the cleanliness of aviation gear parts provided by an embodiment of the present invention; Figure 4 A specific flow chart of through-type cleaning in a method for controlling the cleanliness of aviation gear parts provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0028] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only embodiment.

[0029] Example 1 As mentioned in the background technology, the cleaning methods include manual cleaning and equipment cleaning, among which manual cleaning includes immersion cleaning (immersion brushing), scrubbing, rinsing, etc.; equipment cleaning mainly includes jet cleaning, ultrasonic cleaning, high-flow flushing, combined cleaning, etc. Among them, equipment cleaning mainly uses the ultrasonic cleaning principle. Ultrasonic cleaning uses the cavitation effect generated by ultrasonic vibrators in the cleaning tank to destroy pollutants on the surface of the workpiece and accelerate the dissolution or peeling of pollutants to achieve the purpose of removing pollution. This cleaning method has significant effects and is simple to operate, but a single ultrasonic cleaning method cannot meet the requirements for parts with high precision and cleanliness levels. For the gear parts proposed in this embodiment, in addition to requiring pressure resistance, wear resistance, impact resistance, plastic deformation resistance, surface contact fatigue resistance and bending fatigue resistance, such parts are also required to have higher anti-pollution capabilities; therefore, higher requirements are placed on the cleanliness of the gear parts themselves.

[0030] It can be seen that the existing cleanliness control method is limited to the cleaning process of parts and cleanliness detection in individual links, and cannot achieve cleanliness control in the entire process, resulting in uncontrolled cleanliness of parts. Therefore, it is necessary to improve the traditional cleaning process to achieve the goal of high-efficiency and high-quality cleaning of parts, while improving the working environment and reducing energy consumption.

[0031] In order to solve the above problems and achieve the above purposes, the present embodiment provides a method for controlling the cleanliness of aviation gear parts. The method can be based on the existing cleaning technology and actual conditions on site, combined with the structural characteristics of the parts and their related technical requirements, benchmark the cleanliness standards of such parts, and comprehensively consider the entire processing process of the parts to find out the cleanliness control risk points, and overcome them one by one, and finally form a cleanliness control process suitable for such high-precision gear parts, so as to achieve the goal of high-precision gear parts meeting their corresponding cleanliness level requirements.

[0032] like Figure 3 As shown, this embodiment provides a method for controlling the cleanliness of aviation gear parts, and the specific steps are as follows: Obtain the cleanliness risk points of aviation gear parts during the entire processing process; Divide all cleanliness risk points into pre-processing risk points, intermediate processing risk points, and pre-packaging risk points; Aiming at the pre-treatment risk points, aviation gear parts are processed by grinding and oil particle cleaning in turn; Aiming at the intermediate processing risk points, ultrasonic cleaning and finishing processing are used in turn to process the aviation gear parts; in the turnover process of aviation gear parts, parts boxes and protective gears are used to protect the aviation gear parts; In view of the risk points before packaging, the aviation gear parts are processed in sequence by demagnetization, residual magnetism inspection and three-step cleaning method, and the cleanliness level of the aviation gear parts is evaluated after cleaning.

[0033] In order to facilitate understanding of the above control method mentioned in this embodiment, the following specific description is given: This embodiment provides a set of high-precision gear parts cleanliness control process flow with (deionized water + water-based cleaning agent), hydrocarbon solvent as the cleaning medium, through-type cleaning, vacuum ultrasonic rotary spray composite cleaning, and vacuum drying as the core cleaning process; the processing flow of such gear parts is as follows Figure 1 As shown in the figure, according to the processing flow of parts, the cleanliness control process risk points (also called cleanliness risk points) are identified and Figure 1 The cleanliness risk points are marked with serial numbers ① to ⑧ respectively, and the cleanliness risk points are analyzed as follows: No. ①: Burrs are generated during turning, grinding, gear hobbing and gear grinding during the processing. The deburring process does not remove the burrs thoroughly, and there is a risk of residual tiny burrs; No. ②: Tiny particles adhere to the surface of the parts before heat treatment, which are coated during the heat treatment process and may fall off later; No. ③: There is a risk of foreign matter being introduced into the magnetic flaw detection fluid during magnetic flaw detection; No. ④: There are tiny foreign objects, fibers, etc. left on the parts before inspection; No. ⑤: Factors such as environmental pollution during the turnover and packaging of parts result in the parts cleanliness failing to meet the requirements, i.e. full process control; No. 6: Residual magnetism exists during the processing of parts, and residual metal foam adheres to the parts, making cleaning difficult; No. 7: The arrangement of the cleaning process is unreasonable; adjust the cleaning process according to different ultrasonic frequencies; No. ⑧: After packaging, the parts had slight bumps during the transfer process, resulting in the parts cleanliness failing to meet requirements.

[0034] For the above 8 categories of cleanliness risk points, the cleanliness control process flow of each risk point is as follows: For the cleanliness risk point ①, use grinding wheel and file to remove the tooth along the top circle and end face tooth profile rounding R0.2max, the rest rounding R0.3 max, add felt wheel polishing to remove the residual tiny burrs at the tooth profile transition, such as Figure 2 As shown, check the gears under a stereo microscope for any burrs remaining; R0.2 max means that during the grinding or processing process, a certain edge or corner needs to be ground into an arc shape, and the maximum radius of the arc shall not exceed 0.2 mm. The same is true for R0.3 max and R0.2 max.

[0035] For cleanliness risk points ② and ③, the cleaning process mainly adopts soaking + rinsing + compressed air drying to remove oil stains, metal particles, etc. attached to the surface of parts before heat treatment; cleaning before and after magnetic detection improves the detection quality and removes residual liquid.

[0036] After cleaning, visually inspect the surface of the parts to ensure there are no particles, metal chips or other foreign matter. Cleaning process: manual loading - soaking, rinsing - manual unloading - compressed air drying; Among them, a single tank immersion and rinse tank is used, and the cleaning medium used is a solvent cleaning agent, and the solvent cleaning agent is preferably metalsolv3010; the equipment cleaning time is 3 to 5 minutes.

[0037] For cleanliness risk point ④, the main cleaning process used is immersion rinsing + single-tank ultrasonic cleaning + compressed air drying to remove tiny foreign objects and fibers attached to the surface of parts before inspection, thereby improving the one-time inspection pass rate of parts appearance.

[0038] After cleaning, visually inspect the surface of the parts to ensure there are no particles, metal chips or other foreign matter. Cleaning process: manual loading - ultrasonic cleaning (40-45KHz) - manual unloading - compressed air drying; Among them, a single-tank ultrasonic cleaning machine is used to complete the cleaning, and the ultrasonic generator adopts a fixed frequency of 40-45KHz; the cleaning medium is a water-based cleaning agent (preferably SKH-232) + deionized water, and the ratio of the two is 3% Vol; the specific equipment cleaning time is 3-5min; the heating temperature is 40-55°C.

[0039] In response to the cleanliness risk point ⑤, protective equipment such as parts boxes are used for aviation gear parts to prevent parts from being bumped and damaged during the turnover process, which would cause secondary contamination.

[0040] For cleanliness risk point ⑥, demagnetization and residual magnetism inspection are mainly carried out before final cleaning, using a magnetometer for inspection; residual magnetism no greater than 3GS is considered to have passed the inspection.

[0041] For cleanliness risk point ⑦, it is necessary to clarify the cleaning method of parts before final storage. In this embodiment, the cleaning mechanism of ultrasonic waves is studied. Different from the single-frequency ultrasonic waves used in traditional cleaning processes, different ultrasonic frequencies are used alternately to clean parts according to the cleaning ability of different ultrasonic frequencies on the residual particle size of parts. Finally, the cleaning process flow of gear parts before final storage is formulated, which is as follows: The first step is pre-cleaning: use a single-slot ultrasonic wave with an ultrasonic frequency of 40 to 45 kHz to pre-clean the aviation gear parts after residual magnetism inspection; The second step is through cleaning: deionized water or a certain ratio of cleaning agent and deionized water, through a series of processes such as ultrasonic cleaning, spray washing, ultrasonic cleaning, rinsing, hot air drying, vacuum drying, etc., to remove rust-proof grease, cutting fluid, metal foam, dust, grinding paste and other pollutants on the surface of the workpiece and dry them. The specific process and related parameters are as follows: Figure 4 shown.

[0042] (1) Ultrasonic vibrators are installed on the sides and bottom of the tank, and the ultrasonic generator uses a fixed frequency of 28 to 35 kHz.

[0043] (2) Cleaning medium: deionized water, deionized water + water-based cleaning agent (SKH-232), the cleaning agent concentration ratio is 3% Vol.

[0044] After cleaning, visually check that there are no particles, metal chips or other foreign matter on the surface of the parts.

[0045] The third step is composite cleaning: it integrates multiple cleaning methods. The solvent treatment system used for the entire cleaning is operated under vacuum (<100mbar). By utilizing the combined process of composite cleaning technology, solvents and water-based cleaning media are used alternately in a cleaning chamber, so that the workpiece can be effectively removed of organic and inorganic matter and dried in the cleaning chamber.

[0046] (1) Ultrasonic generator frequency 20~25KHz; (2) Cleaning medium: solvent ISOPARTML FLUID (ExxonMobil), deionized water + water-based cleaning agent (BONDERITE C-NE 5088).

[0047] In this embodiment, the compound cleaning machine has a total of 4 liquid storage tanks, of which tanks 1 and 2 are solvent tanks, and tanks 11 and 12 are deionized water tanks. Through programming control, single cleaning or compound cleaning functions can be realized, and the functions of turning on / off ultrasonic waves, turning on / off basket swing, etc. can be selected during the cleaning process. Finally, after multiple cleaning verifications, program 5 (tank 11-tank 12-tank 1-tank 2-drying) was selected for cleaning of gear parts. After cleaning, it was sent for cleanliness inspection.

[0048] Regarding the cleanliness risk point ⑧, there are slight bumps on the parts during the transfer process after packaging, resulting in the cleanliness of the parts failing to meet the requirements. Specially customized storage packaging protection devices can effectively protect the cleaned parts from bumps and avoid the reintroduction of contaminants.

[0049] In this embodiment, the cleanliness level classification is shown in Table 1: Table 1 shows the classification of cleanliness levels

[0050] Detect and record the number of solid particles of different sizes of 5-15μm, 15-25μm, 25-50μm, and 50-100μm in the residual contaminants on the controlled surface of the parts, and convert the number of particles detected according to the particle size classification to the corresponding number of particles per 1000cm2 of controlled surface listed in the table above.

[0051] The conversion formula is: conversion number = test number × 1000 / controlled surface area measured in square centimeters. Compare the conversion number with Table 1 to determine the actual cleanliness level of the part. Cleanliness identification example: B8 / C7 / D6 / E5 / F4.

[0052] The current cleanliness level requirements for gear parts are: AETF1-D8 / E7 / F7, and there should be no solid particles larger than 200μm.

[0053] This embodiment provides a method for controlling the cleanliness of aviation gear parts, which has the following characteristics: (I) Different cleaning stages use different cleaning media (solvent cleaners, water-based cleaners) to give full play to their respective advantages. Solvent cleaners have strong ability to remove heavy oil stains, so they are arranged in the pretreatment stage and the soaking and brushing stage in the intermediate treatment; water-based cleaners have good ultrasonic effects, so they are arranged in the fine cleaning process after soaking and rinsing to remove heavy oil stains in the intermediate treatment, including the cleaning process of the composite machine, which also selects the procedure of solvent washing and water-based washing for interval cleaning to thoroughly clean the parts.

[0054] (II) Cleaning equipment of different frequencies are arranged in different cleanliness control stages. According to the different removal capabilities of residual particle sizes by ultrasonic frequency, 40-45KHz, 28-35KHz and 20-25KHz oscillating ultrasonic cleaning are used in the intermediate processing stage and pre-packaging process to remove residual particles of different sizes.

[0055] (III) Demagnetization treatment: The magnetism that may be generated during the processing of parts or brought by them themselves should be cleaned and demagnetized before final storage to reduce the difficulty of cleaning.

[0056] (IV) In terms of rust prevention, in the pre-packaging process, in order to prevent the parts from rusting due to incomplete cleaning and drying, the final cleaning of the parts is arranged on a composite cleaning machine with drying function (vacuum low-frequency ultrasonic rough cleaning, vacuum low-frequency ultrasonic fine cleaning, high vacuum drying) to ensure thorough drying.

[0057] (V) In terms of product protection, in order to avoid bumps and scratches during the turnover of parts and the introduction of secondary pollution, different protective devices are customized according to the structural characteristics of the parts.

[0058] (VI) After packaging, the gas phase packaging method is adopted, which can achieve no need for cleaning before assembly, avoid secondary pollution, and save costs at the same time.

[0059] It can be seen that the present embodiment provides a method for controlling the cleanliness of aviation gear parts, that is, a process flow for controlling the cleanliness of high-precision gear parts in an aircraft engine control system. The process includes three stages: pretreatment, intermediate treatment, and pre-packaging and post-packaging. Different cleaning media are used in different cleaning stages; cleaning equipment with different frequencies is arranged in different cleanliness control stages; demagnetization treatment before packaging and cleaning; effective rust prevention; in terms of product protection, different protective devices are customized; after packaging, gas phase packaging is used to achieve cleaning-free before assembly, thereby saving costs and other details, and finally achieve the goal of the corresponding cleanliness level requirements of such parts, and realize the full process cleanliness control of high-precision gear parts. The method can meet the cleanliness level requirements of high-precision gear parts. At present, it has been solidified into the cleanliness control process flow of high-precision gear parts and has been applied in actual production, shortening the time for cleaning of gear parts to reach the standard level by 87%, and improving the cleaning effect by 6 times. The design of the cleanliness control process flow of high-precision gear parts in an aircraft engine control system by the present invention can be extended to the cleanliness control process flow of other parts.

[0060] Example 2 This embodiment provides a method for controlling the cleanliness of aviation gear parts in Embodiment 1 for specific implementation and application, as follows: The specific implementation steps are as follows: Taking the oil pump gear part XX-00-04 as an example, after burr control during mechanical processing, such as active deburring, manual deburring, and finishing control during lathe processing, the cleanliness risk point cleanliness control and cleaning process in other processes are as follows: (1) The following cleaning process is used between processes: Soak and scrub → rinse → blow dry with compressed air.

[0061] (2) Use the following cleaning process before collaboration: Rinse → blow dry with compressed air.

[0062] (3) The following cleaning process is used before the in-process inspection: Soak and scrub → Single tank ultrasonic cleaning → Blow dry with compressed air.

[0063] (4) Cleaning process before in-process inspection: rotary spray cleaning.

[0064] (5) After the process cleaning control, the final cleaning inspection is carried out under a stereo microscope to see if there are any burrs left. Finally, the cleaning and packaging control before final storage are carried out. The cleaning before final storage is divided into rough cleaning and fine cleaning. The main control steps are: (1) Demagnetization and inspection: Check the magnetism before demagnetization; if it is greater than 3GS, demagnetize it in a demagnetizer and check that the residual magnetism should not be greater than 3GS.

[0065] (2) Receive the parts, confirm the number of parts and check that the parts are free of burrs, grinding paste residue, visible particles, scratches, and bumps.

[0066] (3) Pre-washer cleaning: Place the parts from the parts box into the cleaning basket; according to the preset program, clean them in tank 1 and tank 2 respectively, and then use the nozzle to spray and rinse every part of the parts in tank 3.

[0067] (4) Cleaning with a composite cleaning machine: When using a composite cleaning machine for cleaning, according to the preset program, the cleaning process is as follows: Use program 5: tank 11 - tank 12 - tank 1 - tank 2 - dry.

[0068] (5) Single tank ultrasonic cleaning: ① Single tank ultrasonic cleaning for 3 to 5 minutes → ② Use compressed air to blow dry.

[0069] (6) Visual inspection: In an environment with an illumination of not less than 1100 (lx), wear rubber gloves to pick up parts and visually inspect to see if there are any visible particles. Then put the parts from the cleaning basket into the parts box. Parts that meet the cleaning area are selected for cleanliness testing. The final results of the inspection are as follows: AETF1A-D3 / E5 / F4.

[0070] It should be noted that: the present invention also provides implementation methods for different types of parts based on the control method, and the specific implementation measures are as follows: (1) Similar structure of parts For parts with similar structures, the cleanliness control process can refer to the cleanliness control process in the example.

[0071] (2) Parts have surface treatment requirements For parts with surface treatment requirements, the main treatment principle is that surface treated parts cannot be ultrasonically cleaned for a long time. The ultrasonic cleaning time can be reduced by adjusting the program. At the same time, surface treated parts, especially those with coatings such as zinc passivation, cadmium passivation, cadmium titanium passivation, and chrome plating, cannot be cleaned at high temperatures. Therefore, when choosing the cleaning process, the influence of high temperature on the surface treatment layer should be avoided. For parts with coating layers, in order to avoid the coating layer from falling off, ultrasonic cleaning cannot be used. The equipment can be ultrasonically cleaned before coating, and manual scrubbing can be used directly after coating.

[0072] (3) Different parts materials For parts made of rust-prone materials, water-based cleaning processes should be avoided as much as possible, that is, the through-type cleaning process in the present invention can be adopted by shortening the water-based cleaning time and drying in time, or the compound machine solvent cleaning process can be directly adopted.

[0073] It can be seen that the present invention provides a method for controlling the cleanliness of aviation gear parts, which has the following advantages over existing cleanliness control measures: This method ensures that the parts are effectively cleaned at every step from pretreatment, intermediate treatment to packaging by systematically identifying and classifying the cleanliness risk points in the entire processing process. In the pretreatment stage, burrs and oil stains are completely removed through precise grinding and oil particle cleaning, laying a good foundation for subsequent processing. In the intermediate processing stage, ultrasonic cleaning and finishing are used to further remove foreign matter and fiber residues, improving the surface quality of parts. Before packaging, magnetic substances and residual particles are completely removed through demagnetization, residual magnetism inspection and three-step cleaning method, ensuring that the cleanliness level of parts meets or exceeds aviation standards. In addition, the use of gas phase packaging effectively prevents the contamination of parts during storage and transportation. Throughout the process, special attention is paid to the protection of parts, such as using parts box protectors to avoid bumps, and reducing damage to parts through fine filtering and cleaning steps. The combined effect of these measures not only improves the cleanliness and quality of aviation gear parts, but also improves production efficiency and reduces costs, providing strong support for the development of the aviation industry.

[0074] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0075] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and the disclosed concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0076] The further detailed description made in the disclosure cannot be used to determine that the specific implementation modes of the present invention are limited to these. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as belonging to the protection scope of the present invention determined by the submitted claims.

Claims

1. A method for controlling the cleanliness of aviation gear parts, characterized in that: include: Obtain the cleanliness risk points of aviation gear parts during the entire processing process; Divide all cleanliness risk points into pre-processing risk points, intermediate processing risk points, and pre-packaging risk points; Aiming at the pre-treatment risk points, aviation gear parts are processed by grinding and oil particle cleaning in turn; Aiming at the intermediate processing risk points, ultrasonic cleaning and finishing processing are used in turn to process the aviation gear parts; in the turnover process of aviation gear parts, parts boxes and protective gears are used to protect the aviation gear parts; In view of the risk points before packaging, the aviation gear parts are processed in sequence using the demagnetization, residual magnetism inspection and three-step cleaning method, and the cleanliness level of the aviation gear parts is evaluated after cleaning.

2. The method for controlling the cleanliness of aviation gear parts according to claim 1, characterized in that: Cleanliness risk points include the following categories: Category 1: During the machining of aviation gear parts, burrs are generated by turning, grinding, hobbing and grinding, and the burrs are not completely removed, resulting in the risk of residual burrs; Category 2: Particles adhere to the surface of aviation gear parts before heat treatment, and tiny particles are coated during the heat treatment process, which poses a risk of falling off later; Category 3: During magnetic flaw detection, there is a risk of foreign matter being introduced into the magnetic flaw detection fluid; Category 4: Before processing inspection, there is a risk of foreign matter and fiber residue on aviation gear parts; Category 5: There is a risk of environmental pollution during the turnover and packaging of aviation gear parts; Category 6: There is residual magnetism in the processing of aviation gear parts, and there is a risk of residual metal foam adhesion; Category 7: Improper arrangement of the cleaning process leads to the risk of incomplete cleaning.

3. The cleanliness control method for aviation gear parts according to claim 1, characterized in that: Cleanliness risk points also include: Category 8: During the packaging process, there are problems with aviation gear parts being bumped into.

4. The method for controlling the cleanliness of aviation gear parts according to claim 3, characterized in that: After the cleanliness level evaluation is completed, aviation gear parts are packaged using gas phase packaging.

5. The cleanliness control method for aviation gear parts according to claim 1, characterized in that: In view of the pre-treatment risk points, the specific steps for treating aviation gear parts by grinding and cleaning oil particles are as follows: Grinding wheels and files are used to remove burrs along the top circle and end face of the teeth of aviation gear parts. The tooth profile is rounded to R0.2max, and the rest of the parts are rounded to R0.3max. At the same time, felt wheel polishing is added to remove residual burrs at the transition of the tooth profile. After grinding, the residual burrs of aviation gear parts are detected using a stereo microscope; The oil particle removal method adopts a soaking, rinsing and compressed air drying process to remove oil and metal particles attached to the surface of aviation gear parts before heat treatment, and to clean aviation gear parts before and after magnetic detection to remove residual liquid; After cleaning with oil particles, the surface of aviation gear parts is visually inspected.

6. The method for controlling the cleanliness of aviation gear parts according to claim 1, characterized in that: In view of the intermediate processing risk points, the specific steps for processing aviation gear parts by ultrasonic cleaning and finishing are as follows: The process of soaking and rinsing, single tank ultrasonic cleaning and compressed air drying is used to remove foreign matter and fiber residue from aviation gear parts before processing and testing. After the removal of foreign matter and fiber residues, the surface of aviation gear parts is visually inspected for foreign matter and fiber residues.

7. The method for controlling the cleanliness of aviation gear parts according to claim 6, characterized in that: The specific process of the single tank ultrasonic cleaning includes: Mix the water-based cleaning agent and deionized water and place it in a single tank ultrasonic cleaning machine; Set the single tank ultrasonic cleaning machine to a cleaning frequency of 40-45KHz, a cleaning time of 3-5min, and a heating temperature of 40-55°C; Place the aviation gear parts into the single-tank ultrasonic cleaning machine to complete the single-tank ultrasonic cleaning; After the aircraft gear parts are finished, the parts are finished by finishing to reduce burrs and metal chips.

8. The method for controlling the cleanliness of aviation gear parts according to claim 1, characterized in that: In view of the risk points before packaging, the demagnetization, residual magnetism inspection and three-step cleaning methods are used to treat the aviation gear parts in sequence, and the specific steps for evaluating the cleanliness level of aviation gear parts after cleaning are as follows: Demagnetize aviation gear parts, and after demagnetization, use a magnetometer to check residual magnetism. The qualified standard for residual magnetism inspection is: the residual magnetism value is less than or equal to 3GS; The three-step cleaning method is used to treat aviation gear parts. The specific steps are: After the residual magnetism inspection, the aviation gear parts are subjected to pre-cleaning, through-type cleaning and composite cleaning in sequence; wherein the ultrasonic frequencies corresponding to the pre-cleaning, through-type cleaning and composite cleaning are successively reduced to remove residual particles of different sizes; The cleanliness level of cleaned aviation gear parts is tested to achieve cleanliness level assessment.

9. The method for controlling the cleanliness of aviation gear parts according to claim 8, characterized in that: The specific steps of pre-cleaning, pass-through cleaning and composite cleaning of the aviation gear parts after the residual magnetism inspection are as follows: Use single-slot ultrasonic waves with an ultrasonic frequency of 40 to 45 kHz to pre-clean aviation gear parts after residual magnetism inspection; Use multi-slot ultrasonic waves with an ultrasonic frequency of 28 to 35 KHz to clean aviation gear parts; The aviation gear parts are cleaned by vacuum low-frequency ultrasonic rough cleaning with an ultrasonic frequency of 20 to 25 KHz, vacuum low-frequency ultrasonic fine cleaning and high vacuum drying.

10. The method for controlling the cleanliness of aviation gear parts according to claim 9, characterized in that: The multi-slot ultrasonic filter uses six-slot ultrasonic filters, and the filtering accuracy of the six slots ranges from 50um to 5um.

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