CN112403847A - Forming and repairing method for heat-proof layer outside engine shell - Google Patents
Forming and repairing method for heat-proof layer outside engine shell Download PDFInfo
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- CN112403847A CN112403847A CN202011168083.7A CN202011168083A CN112403847A CN 112403847 A CN112403847 A CN 112403847A CN 202011168083 A CN202011168083 A CN 202011168083A CN 112403847 A CN112403847 A CN 112403847A
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- heat
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- proof
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D1/00—Processes for applying liquids or other fluent materials
- B05D1/36—Successively applying liquids or other fluent materials, e.g. without intermediate treatment
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/04—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by exposure to gases
- B05D3/0406—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by exposure to gases the gas being air
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/12—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by mechanical means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
- B05D7/50—Multilayers
- B05D7/52—Two layers
- B05D7/54—No clear coat specified
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D2350/00—Pretreatment of the substrate
- B05D2350/30—Change of the surface
- B05D2350/33—Roughening
- B05D2350/38—Roughening by mechanical means
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Wood Science & Technology (AREA)
- Mechanical Engineering (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
Abstract
The invention discloses a method for forming and repairing an external heat-proof layer of an engine shell, which comprises the steps of installation, coating of a cable boundary primer adhesive, coating of a cable boundary heat-proof coating, spraying of a shell surface primer adhesive, spraying of a shell heat-proof coating, repairing of a defect part and spraying of finish paint; the heat-proof layer formed on the outer surface of the prepared composite material shell has good elongation rate and certain strength, and has good bonding performance with the composite material shell, and the heat-proof coating can protect the stability of the mechanical property of the composite material shell, so that the safety and reliability of missile flight are further improved; in addition, the production efficiency is high, and the operation is simple and practical.
Description
Technical Field
The invention belongs to the technical field of an external heat-proof layer of an engine shell, and particularly relates to a forming and repairing method of the external heat-proof layer of the engine shell.
Background
With the increase of the flying speed and the distance of the solid rocket engine, the problem of pneumatic heating borne by the engine shell is more serious, if proper external heat-proof protection measures are not adopted, under the condition of being heated by pneumatic heating and radiation in the flying process, high temperature directly acts on the composite material engine shell, so that the mechanical property of the composite material engine shell is reduced, and the safety and the reliability of missile flying can be further influenced.
Ablation heat protection is the most widely used heat protection form at present, and mainly adopts a mode of combining spraying and blade coating to enable an outer heat protection coating to form a uniform heat protection coating on the outer surface of a composite engine. The working principle is that as the surface temperature of the elastomer rises, a part of heat is absorbed by the heat capacity of the material in the temperature rising process; at the same time, a part of heat can be introduced into the material through the solid conduction effect. In addition, some heat is scattered into the atmosphere by surface radiation. As the surface temperature continues to rise, the material begins to pyrolyze and carbonize, again absorbing a significant amount of heat. The outer heat shield is typically composed of an undercoat, a heat shield coating, and a topcoat layer. The bottom coating adhesive has the functions of bonding the substrate and the heat-proof coating, so that the reliable bonding of the heat-proof coating is ensured; the heat-proof coating mainly plays a role in heat prevention and heat insulation and is a main material of the outer heat-proof layer; the finish paint has good flexibility, high temperature resistance, aging resistance and static resistance.
Disclosure of Invention
The invention aims to provide a method for forming and repairing a heat-proof layer outside an engine shell, which has high production efficiency and simple operation and aims at overcoming the defects of the prior art.
In order to achieve the purpose, the invention designs a method for forming and repairing an external heat-proof layer of an engine shell, which comprises the following specific processes:
1) installation: firstly, a sample is installed in a random sample manufacturing area of a shell spraying fixture tool, then the shell and the shell spraying fixture tool are installed, and then an adhesive tape is used for winding and fixing a cable on the shell spraying fixture tool;
2) coating a cable boundary primer: polishing the boundary surfaces of the front and rear skirt cables of the shell into matt surfaces by using abrasive paper, and removing dust; then uniformly coating the bottom and gluing the surfaces of the boundary of the front skirt cable and the rear skirt cable for 2-4 times, wherein each time is 5-8 minutes;
3) coating a cable boundary heat-proof coating: after the bottom coating glue is dried, coating a heat-proof coating on the surfaces of the bottom coating glue at the boundaries of the front skirt cable and the rear skirt cable in a blade mode, and curing at normal temperature; then protecting the heat-proof coating layer at the boundary of the front skirt cable and the rear skirt cable by using a polytetrafluoroethylene glass fiber adhesive tape;
4) spraying a primer on the surface of the shell: sanding the spraying surface of the shell and the surface of the sample by using abrasive paper until the fiber of the composite material is in an exposed state, sanding the metal surface, removing dust and cleaning; then spraying the prime coat adhesive on the polished surface of the shell and the polished surface of the sample, checking that no white deposit exists on the coated surface of the prime coat adhesive after airing is finished, and removing the polytetrafluoroethylene glass fiber adhesive tape in the step 3);
5) spraying heat-proof paint on the shell: washing a spraying pipeline, performing trial operation on spraying equipment, coating a heat-proof coating on the shell by using the spraying equipment, airing at room temperature for 10-20 minutes after each spraying, and repeatedly coating the heat-proof coating until the thickness of the heat-proof coating meets the requirement; after the spraying is finished, the part vehicle continues to rotate for 60-120 minutes and is naturally cured, and finally the outer heat-proof coating is polished and trimmed;
6) repairing the defect part: firstly, polishing the defect part to be rough by using sand paper, removing dust, then cleaning the surface to be coated, weighing the heat-proof coating according to the area to be coated, and manually brushing and repairing the defect part according to the step 5); if the heat-proof layer is damaged to the depth of the base material, completely cutting off the defective part, polishing the exposed base material body, and then manually brushing and repairing according to the relevant requirements of the step 5);
7) and (3) spraying finish paint: roughly polishing the outer heat-proof layer by using 200-300-mesh abrasive paper, and finely polishing the outer heat-proof layer by using 700-800-mesh abrasive paper; and then, spraying finish paint, and naturally curing after spraying.
Further, the specific process is carried out in the environment with the temperature of 5-35 ℃ and the relative humidity of less than or equal to 75%.
Further, in the step 2), the boundary surfaces of the front skirt cable and the rear skirt cable of the shell are polished by 60-80-mesh abrasive paper, and polished dust is removed by compressed air for oil removal and dehumidification;
further, in the step 2), if the sagging exists, dipping a clean brush cleaned by No. 120 solvent gasoline into the treating agent to brush the sagging evenly, airing and curing, wherein the curing time is 90-120 minutes, and if the curing time exceeds 90-120 minutes, polishing the sagging to the surface of the base material, brushing the bottom and coating the bottom again;
further, in the step 3), after curing at normal temperature until the shore a hardness of the heat-proof coating layer reaches more than 70, polishing the surface of the heat-proof coating layer by using 60-80-mesh sand paper.
Further, in the step 4), polishing the spraying surface of the shell and the surface of the sample by using 60-80-mesh sand paper, and blowing and removing dust on the surface of the shell by using compressed air for removing oil and moisture; then the polished surface of the shell is repeatedly cleaned by dipping the clean white cloth in ethanol ethyl ester until the shell is scrubbed by the clean undershirt cloth without pollution.
Further, in the step 6), the defect part is firstly roughened by 80# sandpaper, and then the surface to be coated is cleaned by 120# solvent gasoline.
Compared with the prior art, the invention has the following advantages: according to the forming and repairing method of the heat-proof layer outside the engine shell, the heat-proof layer formed on the outer surface of the composite material shell has good elongation rate and certain strength, and has good bonding performance with the composite material shell, and the heat-proof coating can protect the stability of the mechanical property of the composite material shell, so that the safety and reliability of missile flight are further improved; in addition, the production efficiency is high, and the operation is simple and practical.
Drawings
Fig. 1 is a schematic structural view of a shell spraying fixture tool of the invention.
Detailed Description
The invention is described in further detail below with reference to the figures and the specific embodiments.
Examples
1. Preparation of
313 primer coating, WS-02 heat-proof coating and M-01 finish paint;
the whole production process of the outer heat-proof layer is carried out in the environment with the temperature of 15-35 ℃ and the relative humidity of less than or equal to 75%;
preparing samples, including 10 pieces of glass fiber shearing sample bottom plates, 10 pieces of glass fiber tearing-off sample bottom plates, 10 pieces of aluminum shearing sample bottom plates, 10 pieces of aluminum tearing-off sample bottom plates and 4 pieces of random heat-insulation-preventing sample bottom plates;
cleaning the shell spraying fixture tool by using No. 120 gasoline to ensure that the surface of the shell spraying fixture tool is free from oil contamination; in addition, after the tool is dismounted after spraying is finished each time, the coating on the tool is cleaned in time; after the cleaning work is finished, the assembly of the tool can be carried out
2. Installation: installing a sample in a random sample manufacturing area 2 (shown in figure 1) of a shell spraying fixture tool 1, installing a shell and the shell spraying fixture tool, and winding and fixing a cable on the shell spraying fixture tool by using an adhesive tape;
3) coating a cable boundary primer: polishing the boundary surfaces of the front skirt cable and the rear skirt cable of the shell into matt surfaces by using 60-80-mesh abrasive paper, and blowing the polished dust clean by using compressed air for removing oil and moisture; then uniformly brushing the bottom of the boundary surface of the front skirt cable and the rear skirt cable by using a small brush for gluing for 2 times, wherein the interval between every two times is 5 minutes; if the sagging exists, a clean brush cleaned by No. 120 solvent gasoline is dipped in the treating agent to brush the sagging evenly, air and cure the sagging, the curing time is 90-120 minutes, if the curing time exceeds 90-120 minutes, the sagging is polished to the surface of the base material, and the base material is brushed again to coat the bottom and glue;
4) coating a cable boundary heat-proof coating: after bottom coating and air drying, coating a heat-proof coating on the bottom coating surface of the boundary of the front skirt cable and the rear skirt cable by using a putty scraper, curing at normal temperature, and polishing the surface of the heat-proof coating by using 60-80-mesh abrasive paper after the Shore A hardness of the heat-proof coating reaches more than 70 to ensure smooth transition without damaging the other surfaces of the shell; then protecting the heat-proof coating layer at the boundary of the front skirt cable and the rear skirt cable by using a polytetrafluoroethylene glass fiber adhesive tape;
5) spraying a primer on the surface of the shell: polishing the spraying surface of the shell and the surface of the sample by using 60-80-mesh abrasive paper until fibers of the composite material are in an exposed state, sanding the metal surface, blowing clean dust on the surface of the shell by using compressed air for removing oil and moisture, and repeatedly cleaning the polished surface of the shell by dipping clean white cloth in ethanol ethyl ester until the shell is scrubbed by using clean undershirt cloth without pollution; spraying is required within 12 hours of metal polishing and within 24 hours of composite material polishing; finally, spraying the bottom coating adhesive on the polished surface of the shell and the polished surface of the sample by using a manual spray gun, wherein the spraying process is carried out by using two posts, one person sprays the bottom coating adhesive for observation, the spraying is ensured to be completely covered and no spray leakage exists, after the airing is finished, the coated surface of the bottom coating adhesive is checked to have no white deposits, and the polytetrafluoroethylene glass fiber adhesive tape in the step 4) is removed;
6) spraying heat-proof paint on the shell: washing a spraying pipeline by using ethyl acetate or 120# gasoline, performing trial operation on spraying equipment, coating a heat-proof coating on the shell by using the spraying equipment, airing at room temperature for more than 10 minutes after each spraying, repeatedly coating the heat-proof coating, wherein the thickness of each layer of the sprayed coating is less than or equal to 0.3mm until the thickness of the heat-proof coating meets the requirement; after the spraying is finished, the part vehicle continues to rotate for more than 60 minutes to prevent sagging, and natural curing is carried out at the same time, wherein the shore A hardness of the heat-proof coating reaches more than 70; polishing and finishing the outer heat-proof coating after the hardness meets the requirement;
7) repairing the parts with insufficient thickness, poor forming and accidental damage: firstly, polishing the part with insufficient spraying thickness or local damage on the surface layer to be rough by using No. 80 abrasive paper, cleaning dust by using clean compressed air, then cleaning the surface to be coated by using No. 120 solvent gasoline, weighing the heat-proof coating according to the area to be coated, and manually brushing and repairing the accidental damage according to the step 6); if the heat-proof layer is damaged to the depth of the base material, completely cutting off the damaged part, polishing the exposed base material body, and then manually brushing and repairing according to the relevant requirements of the step 6);
8) and (3) spraying finish paint: roughly polishing the outer heat-proof layer by using 200-300 meshes of abrasive paper, and finely polishing the outer heat-proof layer by using 800 meshes of abrasive paper; and then, spraying finish paint, and naturally curing for at least 48h after spraying.
Claims (7)
1. A method for forming and repairing a heat-proof layer outside an engine shell is characterized in that: the specific process is as follows:
1) installation: firstly, a sample is installed in a random sample manufacturing area of a shell spraying fixture tool, then the shell and the shell spraying fixture tool are installed, and then an adhesive tape is used for winding and fixing a cable on the shell spraying fixture tool;
2) coating a cable boundary primer: polishing the boundary surfaces of the front and rear skirt cables of the shell into matt surfaces by using abrasive paper, and removing dust; then uniformly coating the bottom and gluing the surfaces of the boundary of the front skirt cable and the rear skirt cable for 2-4 times, wherein each time is 5-8 minutes;
3) coating a cable boundary heat-proof coating: after the bottom coating glue is dried, coating a heat-proof coating on the surfaces of the bottom coating glue at the boundaries of the front skirt cable and the rear skirt cable in a blade mode, and curing at normal temperature; then protecting the heat-proof coating layer at the boundary of the front skirt cable and the rear skirt cable by using a polytetrafluoroethylene glass fiber adhesive tape;
4) spraying a primer on the surface of the shell: sanding the spraying surface of the shell and the surface of the sample by using abrasive paper until the fiber of the composite material is in an exposed state, sanding the metal surface, removing dust and cleaning; then spraying the prime coat adhesive on the polished surface of the shell and the polished surface of the sample, checking that no white deposit exists on the coated surface of the prime coat adhesive after airing is finished, and removing the polytetrafluoroethylene glass fiber adhesive tape in the step 3);
5) spraying heat-proof paint on the shell: washing a spraying pipeline, performing trial operation on spraying equipment, coating a heat-proof coating on the shell by using the spraying equipment, airing at room temperature for 10-20 minutes after each spraying, and repeatedly coating the heat-proof coating until the thickness of the heat-proof coating meets the requirement; after the spraying is finished, the part vehicle continues to rotate for 60-120 minutes and is naturally cured, and finally the outer heat-proof coating is polished and trimmed;
6) repairing the defect part: firstly, polishing the defect part to be rough by using sand paper, removing dust, then cleaning the surface to be coated, weighing the heat-proof coating according to the area to be coated, and manually brushing and repairing the defect part according to the step 5); if the heat-proof layer is damaged to the depth of the base material, completely cutting off the defective part, polishing the exposed base material body, and then manually brushing and repairing according to the relevant requirements of the step 5);
7) and (3) spraying finish paint: roughly polishing the outer heat-proof layer by using 200-300-mesh abrasive paper, and finely polishing the outer heat-proof layer by using 700-800-mesh abrasive paper; and then, spraying finish paint, and naturally curing after spraying.
2. The method for forming and repairing the heat shield layer outside the engine housing according to claim 1, wherein: the specific process is carried out in the environment with the temperature of 5-35 ℃ and the relative humidity of less than or equal to 75%.
3. The method for forming and repairing the heat shield layer outside the engine housing according to claim 1, wherein: in the step 2), the boundary surfaces of the front skirt cable and the rear skirt cable of the shell are polished by 60-80-mesh sand paper, and the polished dust is removed by compressed air for oil removal and dehumidification.
4. The method for forming and repairing the heat shield layer outside the engine housing according to claim 1, wherein: and in the step 2), if the sagging exists, dipping a clean brush cleaned by No. 120 solvent gasoline into the treating agent to brush the sagging uniformly, airing and curing, wherein the curing time is 90-120 minutes, and if the curing time exceeds 90-120 minutes, polishing the sagging to the surface of the substrate, brushing the bottom and coating the adhesive again.
5. The method for forming and repairing the heat shield layer outside the engine housing according to claim 1, wherein: and in the step 3), after curing at normal temperature until the Shore A hardness of the heat-proof coating layer reaches more than 70, polishing the surface of the heat-proof coating layer by using 60-80-mesh sand paper.
6. The method for forming and repairing the heat shield layer outside the engine housing according to claim 1, wherein: in the step 4), polishing the spraying surface of the shell and the surface of the sample by using 60-80-mesh abrasive paper, and blowing and removing dust on the surface of the shell by using compressed air for removing oil and moisture; then the polished surface of the shell is repeatedly cleaned by dipping the clean white cloth in ethanol ethyl ester until the shell is scrubbed by the clean undershirt cloth without pollution.
7. The method for forming and repairing the heat shield layer outside the engine housing according to claim 1, wherein: in the step 6), the defect part is firstly ground to be rough by using No. 80 abrasive paper, and then the surface to be coated is cleaned by using No. 120 solvent gasoline.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011168083.7A CN112403847A (en) | 2020-10-27 | 2020-10-27 | Forming and repairing method for heat-proof layer outside engine shell |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011168083.7A CN112403847A (en) | 2020-10-27 | 2020-10-27 | Forming and repairing method for heat-proof layer outside engine shell |
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| CN112403847A true CN112403847A (en) | 2021-02-26 |
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| CN202011168083.7A Pending CN112403847A (en) | 2020-10-27 | 2020-10-27 | Forming and repairing method for heat-proof layer outside engine shell |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115870196A (en) * | 2022-12-28 | 2023-03-31 | 湖北三江航天江北机械工程有限公司 | Scraping and forming method for external heat-proof layer of combustion chamber shell |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108953001A (en) * | 2018-07-11 | 2018-12-07 | 湖北航聚科技有限公司 | A kind of outer heat shield production method of solid propellant rocket |
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2020
- 2020-10-27 CN CN202011168083.7A patent/CN112403847A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108953001A (en) * | 2018-07-11 | 2018-12-07 | 湖北航聚科技有限公司 | A kind of outer heat shield production method of solid propellant rocket |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115870196A (en) * | 2022-12-28 | 2023-03-31 | 湖北三江航天江北机械工程有限公司 | Scraping and forming method for external heat-proof layer of combustion chamber shell |
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Application publication date: 20210226 |
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