CN114318204A - Remanufacturing and repairing process for airplane shoulder shaft - Google Patents
Remanufacturing and repairing process for airplane shoulder shaft Download PDFInfo
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- CN114318204A CN114318204A CN202111544516.9A CN202111544516A CN114318204A CN 114318204 A CN114318204 A CN 114318204A CN 202111544516 A CN202111544516 A CN 202111544516A CN 114318204 A CN114318204 A CN 114318204A
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- 238000000034 method Methods 0.000 title claims abstract description 44
- 230000008569 process Effects 0.000 title claims abstract description 39
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- 238000000576 coating method Methods 0.000 claims abstract description 24
- 238000005260 corrosion Methods 0.000 claims abstract description 16
- 239000000843 powder Substances 0.000 claims abstract description 16
- 230000007797 corrosion Effects 0.000 claims abstract description 14
- 238000004880 explosion Methods 0.000 claims abstract description 14
- 229910001220 stainless steel Inorganic materials 0.000 claims abstract description 12
- 239000010935 stainless steel Substances 0.000 claims abstract description 12
- 238000005488 sandblasting Methods 0.000 claims abstract description 11
- 238000000227 grinding Methods 0.000 claims abstract description 10
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims abstract description 8
- 238000001514 detection method Methods 0.000 claims abstract description 8
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- 238000004140 cleaning Methods 0.000 claims abstract description 4
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- 238000007689 inspection Methods 0.000 claims abstract description 4
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 claims description 8
- 239000011159 matrix material Substances 0.000 claims description 7
- 238000002485 combustion reaction Methods 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 5
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- OBOXTJCIIVUZEN-UHFFFAOYSA-N [C].[O] Chemical compound [C].[O] OBOXTJCIIVUZEN-UHFFFAOYSA-N 0.000 claims description 4
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 claims description 4
- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 claims description 4
- 239000001294 propane Substances 0.000 claims description 4
- 229910052593 corundum Inorganic materials 0.000 claims description 3
- 239000010431 corundum Substances 0.000 claims description 3
- 239000004576 sand Substances 0.000 claims description 3
- 239000007789 gas Substances 0.000 description 5
- 229910000831 Steel Inorganic materials 0.000 description 4
- 238000004372 laser cladding Methods 0.000 description 4
- 230000008439 repair process Effects 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
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- 239000003921 oil Substances 0.000 description 3
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- 238000005336 cracking Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
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- 238000005536 corrosion prevention Methods 0.000 description 1
- 238000010283 detonation spraying Methods 0.000 description 1
- 238000006056 electrooxidation reaction Methods 0.000 description 1
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- 229910052736 halogen Inorganic materials 0.000 description 1
- -1 halogen ion Chemical class 0.000 description 1
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Abstract
The invention relates to the technical field of remanufacturing and repairing of parts, in particular to a remanufacturing and repairing process of an airplane shoulder shaft, which comprises the following steps: removing corrosion defects on the surface of the part in a turning mode, wherein the size of the turning surface is not more than 0.2 mm; stress relieving treatment is carried out, and oil removal and cleaning are carried out by adopting acetone; carrying out surface sand blasting pretreatment; spraying and repairing the part by using 316L stainless steel powder and adopting explosion spraying according to process parameters, and inspecting the appearance of the coating after the spraying is finished; grinding the sprayed part and inspecting the size and the surface roughness of the part; stress is eliminated, and flaw detection inspection is carried out on the surface of the part coating by a fluorescent flaw detection technology; and verifying the size and the process requirement of the repaired part assembling machine. The invention meets the requirement of the assembly size of the product, improves the corrosion resistance of the repaired surface, reduces the subsequent re-corrosion probability and ensures the use safety of the airplane suspended beam device.
Description
Technical Field
The invention relates to the technical field of remanufacturing and repairing of parts, in particular to a remanufacturing and repairing process of an airplane shoulder shaft.
Background
The shoulder shaft is a part for connecting the aircraft hanging beam and the aircraft body structure, is made of 30CrMnSiNi2A ultrahigh-strength steel, and the cylindrical surface is used for static assembly, so that the shoulder shaft is not subjected to electroplated layer corrosion prevention treatment, is in a vibration environment for a long time, is easy to generate fretting wear, and is exposed in air, particularly in coastal Cl ion-containing humid air, and is easy to generate pitting corrosion and even expand into severe corrosion. The shoulder shaft is expensive in material and complex in processing, so that the value is high, and in the remanufacturing process, the corrosion resistance of the shoulder shaft is improved while the surface size of the cylinder is recovered, so that the service life of a product after remanufacturing is prolonged.
The 316L stainless steel has the standard designation 022Cr17Ni2Mo2, mainly contains Cr, Ni and Mo elements, so the steel has excellent corrosion resistance, and meanwhile, the Mo content ensures that the steel has excellent pitting resistance, and can be safely applied to halogen ion environments containing Cl ions and the like. The powder prepared by the material is a mature product in the market, such as Diamalloy 1003 type 316L powder of Metco company, and the powder can be prepared by coating by a thermal spraying process. CN201710483509.X, an optimization process for laser cladding 316L stainless steel, which is a method for repairing No. 45 steel base material by using laser cladding 316L stainless steel powder, is suitable for repairing damage of local pits or scratches, but has certain difficulty in large-area corrosion in the circumferential direction of a cylinder, and the laser cladding technology needs to melt a base body, so that an HAZ (heat affected zone) is generated, the strength of the HAZ zone is reduced, and fatigue cracks are generated on the working surface of the cylinder bearing larger stress.
Disclosure of Invention
Aiming at the technical problem, the invention provides a remanufacturing and repairing process of an airplane shoulder shaft.
The technical problem to be solved by the invention is realized by adopting the following technical scheme:
an aircraft shoulder shaft remanufacturing and repairing process comprises the following steps:
removing corrosion defects on the surface of the part in a turning mode, wherein the size of the turning surface is not more than 0.2 mm;
secondly, stress relief treatment is carried out, and oil removal and cleaning are carried out by adopting acetone;
thirdly, performing surface sand blasting pretreatment;
fourthly, spraying and repairing the part by using 316L stainless steel powder and adopting explosion spraying according to process parameters, and inspecting the appearance of the coating after the spraying is finished;
grinding the sprayed part and inspecting the size and the surface roughness of the part;
sixthly, stress relief treatment is carried out, and flaw detection inspection is carried out on the surface of the part coating through a fluorescent flaw detection technology;
and (seventhly), verifying the size and the process requirement of the repaired part assembling machine.
Preferably, the stress relief treatment in step (ii) and step (six) are both: in a heat treatment furnace, the temperature is 190 +/-10 ℃ and the time is more than 4 h.
Preferably, the parameters of the sand blasting process in the step (three) are as follows: the white corundum sand is 54-60 meshes, the pressure of compressed air is 0.45-0.55 MPa, and the sand blasting distance is 150-200 mm.
Preferably, the process parameters of the explosion spraying in the step (four) are as follows:
gas combustion: acetylene and propane;
explosion frequency: 4 guns/second;
spraying and gun stopping frequency: spraying again after the substrate is cooled to be lower than 50 ℃ every time the spraying is carried out for 1-2 times;
gun filling rate: 65 percent;
oxygen-carbon ratio: 1.026;
powder feeding rate: 10 g/min;
spraying distance: 260 mm-300 mm.
Preferably, the spraying distance is in particular 280 mm.
Preferably, the substrate temperature at the time of explosion spraying in step (four) is not higher than 150 ℃.
Preferably, the single-sided margin of the explosive spraying in the step (four) is at least 0.07 mm.
The invention has the beneficial effects that:
compared with the prior art, the invention replaces the traditional welding and laser cladding repair process by the explosive spraying 316L stainless steel powder process, avoids the problem that the mechanical property of the matrix is reduced due to the HAZ region generated by excessive heat input, realizes the large-area pitting remanufacturing and repairing of the surface of the ultrahigh-strength steel shoulder shaft, meets the requirement of the assembly size of a product, improves the corrosion resistance of the repaired surface, reduces the subsequent re-corrosion probability, and ensures the use safety of the airplane hanging beam device.
Drawings
The invention is further illustrated with reference to the following figures and examples:
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a schematic view of the microstructure of 316L stainless steel coating after detonation spraying.
Detailed Description
In order to make the technical means, the creation features, the achievement purposes and the effects of the invention easy to understand, the invention is further explained in the following with the accompanying drawings and the embodiments.
As shown in fig. 1, the remanufacturing and repairing process of the aircraft shoulder shaft comprises the following specific steps:
and (I) turning to remove defects. The corrosion defect of the assembly surface of the cylindrical part is removed in a turning mode, and the size of the assembly surface is uniformly reduced, so that the coaxiality of the assembly surface is not affected; to prevent the overall strength of the part from being significantly affected, the turning surface size removal does not exceed 0.2 mm.
And (II) stress relief. And (5) after the turning is finished, performing stress relief treatment in a heat treatment furnace at the temperature of 190 +/-10 ℃ for more than 4 hours. The method is used for eliminating stress generated by turning and preventing the substrate from cracking.
And (III) oil removal and cleaning. And (5) after the stress of the part is eliminated, using cotton cloth, gauze or surface treatment wiping cloth to dip acetone to clean the part to be sprayed until the oil stain on the surface is completely removed.
And (IV) carrying out surface sand blasting. Carrying out sand blasting treatment on the assembly surface of the cylinder of the part, wherein the selected sand blasting process comprises the following steps: the white corundum sand is 54-60 meshes, the pressure of compressed air is 0.45-0.55 MPa, and the sand blasting distance is 150-200 mm.
And (V) spraying. Spraying 316L stainless steel powder by adopting an explosion spraying process, and monitoring the temperature of a part matrix to be not higher than 150 ℃ in the spraying process. In order to facilitate the subsequent grinding of the coating, the margin of 0.07mm on at least one side is ensured during spraying. After the spraying was completed, the appearance of the coating was checked. The coating surface is uniform and continuous without flaking, spalling, chipping, bubbles and visible cracks. The maximum size of the spray repair is 0.4 mm.
The technological parameters are as follows:
gas combustion: acetylene and propane; the propane gas is added, and has lower combustion heat value than acetylene under the same carbon content, so that the gas expansion ratio after combustion is larger, the flame flow temperature can be further reduced, and the flame flow speed can be further improved.
Explosion frequency: 4 guns/second (ensure that the temperature of the matrix is not higher than 150 ℃ and ensure the powdering rate at the same time);
spraying and gun stopping frequency: spraying for 1-2 times (one time procedure is one time), cooling to the temperature of the matrix lower than 50 ℃, and spraying again until the required thickness (ensuring that the temperature of the matrix is not higher than 150 ℃);
gun filling rate (ratio of filling gas volume to gun tube inner cavity volume): 65 percent. Too high a rate of gun filling can result in too high a bore pressure; if the gun filling rate is low, the flame flow speed is insufficient, and the metallographic specimen has larger porosity;
oxygen-carbon ratio: 1.026. the oxygen-carbon ratio is more than 1 to ensure the full combustion of the fuel gas; if too large, the flame flow is diluted and the temperature is lowered.
Powder feeding rate: 10g/min, and adjusting the powder feeding rate to a proper forming shape after the process parameters are determined.
Spraying distance: 260 mm-300 mm. However, the specific thickness is preferably 280mm because the porosity of the coating is large when the distance is 260mm and the powder is easily over-melted when the distance is 300 mm.
And (VI) grinding. The size and the surface roughness of the sprayed part are ensured by grinding, and a silicon carbide grinding wheel is used for coating grinding.
And (seventhly) checking. And after the part is machined, the size and the surface roughness are checked according to the drawing of the part, so that the drawing requirements are met.
(eighth) stress relief. And (4) performing stress relief treatment on the part which is qualified after inspection in a heat treatment furnace at the temperature of 190 +/-10 ℃ for more than 4 h. The method is used for eliminating stress generated by grinding processing and preventing the coating from cracking.
And (ninthly) flaw detection. The surface of the fluorescent flaw detection part coating has no crack display.
And (ten) assembling and verifying. The shoulder shaft installation machine is matched with the verification size and needs to meet the process requirement.
Compared with the supersonic flame spraying process (see Guomangqiu, Zhang Xinghua, Juanling Red, etc.. the supersonic flame spraying 316L stainless steel coating performance research [ J ] failure analysis and prevention, 2013, 8 (4): 216-221), the repair process disclosed by the invention utilizes intermittent explosion energy spraying, belongs to pulse spraying, has higher particle flight speed, lower powder and matrix heating capacity and less oxidation, and ensures that the prepared coating has lower porosity and firmer combination.
As shown in FIG. 2, the typical coating structure of the 316L stainless steel sprayed by explosion can be seen, the 316L stainless steel powder has good flattening plastic deformation effect, the coating structure is compact, and the porosity of the coating reaches below 0.5% by metallographic analysis. The coating is used for corrosion repair of the steel shoulder shaft, can reduce the difference of thermal expansion coefficients of the coating and a substrate, prevents the coating from peeling off caused by the temperature change of the use environment of a product, and simultaneously reduces the potential difference between dissimilar metals and prevents electrochemical corrosion; meanwhile, the coating contains Mo element and Cr element with higher content, so that the corrosion resistance can be improved, and the pitting corrosion rate can be reduced.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (7)
1. An aircraft shoulder shaft remanufacturing and repairing process is characterized in that: the method comprises the following steps:
removing corrosion defects on the surface of the part in a turning mode, wherein the size of the turning surface is not more than 0.2 mm;
secondly, stress relief treatment is carried out, and oil removal and cleaning are carried out by adopting acetone;
thirdly, performing surface sand blasting pretreatment;
fourthly, spraying and repairing the part by using 316L stainless steel powder and adopting explosion spraying according to process parameters, and inspecting the appearance of the coating after the spraying is finished;
grinding the sprayed part and inspecting the size and the surface roughness of the part;
sixthly, stress relief treatment is carried out, and flaw detection inspection is carried out on the surface of the part coating through a fluorescent flaw detection technology;
and (seventhly), verifying the size and the process requirement of the repaired part assembling machine.
2. The remanufacturing and repairing process of an aircraft shoulder shaft as claimed in claim 1, wherein the remanufacturing and repairing process comprises the following steps: the stress relief treatment in the step (II) and the step (VI) is that: in a heat treatment furnace, the temperature is 190 +/-10 ℃ and the time is more than 4 h.
3. The remanufacturing and repairing process of an aircraft shoulder shaft as claimed in claim 1, wherein the remanufacturing and repairing process comprises the following steps: the sand blasting process parameters in the step (III) are as follows: the white corundum sand is 54-60 meshes, the pressure of compressed air is 0.45-0.55 MPa, and the sand blasting distance is 150-200 mm.
4. The remanufacturing and repairing process of an aircraft shoulder shaft as claimed in claim 1, wherein the remanufacturing and repairing process comprises the following steps: the technological parameters of the explosion spraying in the step (four) are as follows:
gas combustion: acetylene and propane;
explosion frequency: 4 guns/second;
spraying and gun stopping frequency: spraying again after the substrate is cooled to be lower than 50 ℃ every time the spraying is carried out for 1-2 times;
gun filling rate: 65 percent;
oxygen-carbon ratio: 1.026;
powder feeding rate: 10 g/min;
spraying distance: 260 mm-300 mm.
5. The remanufacturing and repairing process of an aircraft shoulder shaft as claimed in claim 4, wherein the remanufacturing and repairing process comprises the following steps: the spraying distance is 280 mm.
6. The remanufacturing and repairing process of an aircraft shoulder shaft as claimed in claim 1, wherein the remanufacturing and repairing process comprises the following steps: and (IV) the temperature of the matrix is not higher than 150 ℃ during explosion spraying.
7. The remanufacturing and repairing process of an aircraft shoulder shaft as claimed in claim 1, wherein the remanufacturing and repairing process comprises the following steps: and (IV) performing explosion spraying to ensure that the single-side allowance is at least 0.07 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111544516.9A CN114318204A (en) | 2021-12-16 | 2021-12-16 | Remanufacturing and repairing process for airplane shoulder shaft |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111544516.9A CN114318204A (en) | 2021-12-16 | 2021-12-16 | Remanufacturing and repairing process for airplane shoulder shaft |
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| Publication Number | Publication Date |
|---|---|
| CN114318204A true CN114318204A (en) | 2022-04-12 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111544516.9A Pending CN114318204A (en) | 2021-12-16 | 2021-12-16 | Remanufacturing and repairing process for airplane shoulder shaft |
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| Country | Link |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180245638A1 (en) * | 2017-02-28 | 2018-08-30 | Caterpillar Inc. | Method for coating a component |
| CN113789495A (en) * | 2021-08-30 | 2021-12-14 | 国营芜湖机械厂 | 1Cr15Ni4Mo3N matrix surface coating composite repair process |
-
2021
- 2021-12-16 CN CN202111544516.9A patent/CN114318204A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180245638A1 (en) * | 2017-02-28 | 2018-08-30 | Caterpillar Inc. | Method for coating a component |
| CN113789495A (en) * | 2021-08-30 | 2021-12-14 | 国营芜湖机械厂 | 1Cr15Ni4Mo3N matrix surface coating composite repair process |
Non-Patent Citations (2)
| Title |
|---|
| 曹强等: "浅析军用飞机修理中的表面工程技术及应用" * |
| 高继文等: "超音速火焰喷涂316L不锈钢涂层在零件尺寸修复中的应用" * |
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Application publication date: 20220412 |