What is the processing technology of manual sandblasting machine?
1. Surface pretreatment: pretreatment such as electroplating, painting, anode, Teflon, rubber, plastic, coated metal, spray welding, gold plating, titanium plating, etc. to increase the surface adhesion of products.
2. Surface beautification processing: decorative processing and matt or matte surface treatment of various metal or nonmetal products. Such as: gold, glass, acrylic, Polaroid, crystal glass and other surface atomization treatment, and can make the surface of processed products appear metallic luster or natural color.
3. Surface cleaning treatment: after metal oxide layer or heat treatment, black skin, surface rust and black skin are removed, non-metallic ceramic surfaces and black spots are colored, removed or painted for regeneration, and rubber molds and gravity die-casting molds are used to remove oxides, residues or release agents.
4, plastic burr removal processing: plastic, rubber, electric wood products, aluminum die castings and other burr removal. Surface dressing and deburring of electronic parts and magnetic cores.
5. Etching: surface modification and etching of metals and nonmetals. Such as: gold, jade, crystal, agate, seal, stone, ceramic wood and so on.
6. Processing of electronic parts: packaging of electronic parts, removal of overflow burrs, removal of printed characters on the surface of finished electronic parts, fogging etching of silicon wafers, and removal and cleaning of ceramic electrothermal materials on the back of wafers.
7. Stress relieving treatment: cleaning, derusting, paint removal and extinction, renovation and stress relieving treatment for aerospace industry and national defense weapons.
8. Mold processing: mold surface, sandblasting, biting, cleaning, matte surface treatment, tire mold, shoe mold, bakelite mold, conductive rubber mold, electronic product mold, etc.
9. Sandblasting: The minimum volume of metal sandblasting products is 0.2mm, and the maximum is not more than 5 tons. Matte surface treatment of large flat stainless steel. Non-metallic sand blasting, large flat glass, acrylic automatic grinding, plastic burr removal.
What are the main applications of sandblasting technology?
The sandblasting process is mainly to treat the surface of the material, so that other coatings can be better adsorbed on the surface of the material. Similarly, the sandblasting process can produce a special metal flash effect on the surface of the workpiece. So, do you know the main application of sandblasting technology?
Sand blasting technology for removing oxide scale.
After heat treatment, the oxide scale and residual salt can not only be removed by sandblasting, but also improve the surface smoothness of parts, especially for molds and precision parts with complex shapes. For example, sandblasting after heat treatment can not only damage the cutting edge of the file, but also improve its service life.
After hot rolling, various rare metal plates can also be cleaned by sandblasting to prepare for cold rolling and improve the surface quality of plates.
Clean the rough surface of precision castings.
Sand blasting is the most economical and effective method to clean the scale and residue on the surface of precision castings, especially for cleaning and polishing precision castings with complex shapes and no allowance. At the same time, it can play a role in polishing and improve the surface smoothness of castings; For example: aero-engine turbine blades, surgical instruments, jewelry, etc.
Cleaning die castings by sandblasting can make the parts appear the same metallic color and make the appearance of the parts more beautiful. If the liquid shot peening effect is good, the surface hardness and corrosion resistance of the parts can be improved. Such as: various musical instrument shells, picture frames, jewelry, etc.
For aluminum, copper and other metals cast in sand mold, sandblasting can also achieve higher surface quality, saving many intermediate process links.
3. Remove the tiny burr of the machined workpiece.
Although the burr is small, it is very harmful. With the progress of science and technology, mechanical parts become more and more complex, with higher and higher precision requirements and very strict application conditions. Burrs are not allowed, such as 3C communication industry, textile machinery parts, hydraulic components, precision and complex parts of aerospace industry, medical instruments, castings on dentures, etc. If the process parameters are selected reasonably, the efficiency and quality of burr removal by sandblasting can be high, and small rounded corners can appear at the joint of two surfaces.
Prepare for other surface treatment processes.
Parts are pretreated by sandblasting before electroplating, and the electroplating layer has strong adhesion, especially hard chromium plating. For example: chromium plating of engine piston ring, pear-shaped surface of silk roller of textile machine, etc.
For painting parts and spraying parts, sandblasting before spraying can enhance the adhesion of the coating; The bonded parts are bonded by sandblasting, with good quality and stronger bonding.
5. Surface decoration sandblasting process.
Sandblasting is an effective process for parts that need smooth surface and are not allowed to reflect light, such as surgical instruments.
Others, such as frosted glassware and patterns, the processing of sand surface of dashboard and plastic wire drawing paper, the mirror surface of monocrystalline silicon, and the plush processing of special fabrics, are widely used.
The main application of sandblasting technology is to clean dirt and rust.
Various molds, such as forging molds, stamping molds, rubber molds, tire molds, plastic compression molds, glass products molds, etc. After a period of use, it will inevitably be contaminated with dirt and release agent and other burn marks. The effect of sand blasting cleaning is very obvious, which can improve the service life of the mold. Sandblasting can meet the medical sterilization requirements of food molds;
Sand blasting can improve the pressure resistance of ceramic components in electronic industry; The old and new mechanical parts and auto parts can be turned over by sandblasting technology to achieve the effect of exchanging the old for the new.
7. Polishing treatment of sand blasting process
As a polishing method, sandblasting has an excellent effect, especially for the polishing of parts with complex surfaces, such as blades of turbomachinery and various mold surfaces, which is incomparable to any other method. Sandblasting polishing ceramics, diamonds and gold and silver jewelry is the most economical method.
Improve the performance of mechanical parts
After sandblasting, not only the smoothness of mechanical parts can be improved by 0.5- 1 on the original basis, but also there are microscopic uniform pits on the sprayed surface, which can keep the storage of lubricating oil and improve its lubrication conditions, thus prolonging the service life of parts and reducing the noise of mechanical operation. Such as gears, crankshafts, textile machinery, sewing machinery, etc.
The fatigue strength and corrosion resistance of mechanical parts can be significantly improved by sand blasting, especially liquid shot blasting. Such as springs, turbine blades, etc.
Small surface defects of mechanical parts and castings are easily exposed after sandblasting, which is helpful for the inspection and flaw detection of parts cracks.
What are the technological steps and principles of sandblasting?
Sand blasting technology is driven by compressed air to form a high-speed jet beam, which sprays materials to the surface of the workpiece to be treated at high speed, so that the surface appearance of the workpiece changes. Due to the impact and cutting action of abrasive on the workpiece surface, the workpiece surface has a certain cleanliness and different roughness, and the mechanical properties of the workpiece surface are improved.
Working principle: The liquid sandblasting machine uses the slurry pump as the supply power of the slurry, and delivers the uniformly stirred slurry to the spray gun through the slurry pump, and the compressed air is used as the acceleration power of the slurry, and enters the spray gun through the gas pipeline.
In the spray gun, the compressed air accelerates the grinding fluid entering the spray gun, and sprays it through the nozzle to the machining surface, thus achieving the expected machining purpose. In the liquid sandblasting machine, the abrasive pump is the feeding power and the compressed air is the accelerating power.
Extended data
Main application scope of sandblasting:
1, workpiece painting, workpiece bonding pretreatment and sandblasting can remove all dirt such as rust on the surface of the workpiece and establish a very important basic drawing on the surface of the workpiece.
Moreover, different degrees of roughness can be achieved by replacing abrasives with different particle sizes, such as spreading abrasives, which greatly improves the bonding force between the workpiece and the coating and electroplating materials. Or the bonding part is more firmly bonded and the quality is better.
2. Cleaning and polishing of rough surfaces of castings and workpieces after heat treatment. Sand blasting can clean all the dirt on the surface of castings and workpieces after heat treatment, polish the surface of workpieces, improve the smoothness of workpieces, expose the uniform metal color of workpieces, and make the appearance of workpieces more beautiful.
3. Burr cleaning and surface beautification sandblasting of machined parts can clean up tiny burrs on the surface of the workpiece, make the surface of the workpiece smoother, eliminate the harm of burrs and improve the grade of the workpiece. Moreover, sandblasting can make a small fillet at the junction of the workpiece surface, which makes the workpiece look more beautiful and precise.
4, improve the mechanical properties of parts, mechanical parts after sandblasting, can produce uniform and fine concave and convex surface on the surface of parts, so that lubricating oil can be stored, thereby improving lubrication conditions, reducing noise and improving the service life of machinery.
5, the role of light decoration For some special-purpose workpieces, sandblasting can achieve different reflections or matt at will. For example, the polishing of stainless steel workpieces and plastics, the polishing of jade articles, the extinction of wooden furniture surfaces, the patterns on frosted glass surfaces, and the roughening of cloth surfaces.
Baidu encyclopedia-sandblasting technology
Differences and advantages between sandblasting and shot blasting.
First, let's take a look at sandblasting and sandblasting machines.
Sand blasting is a method of blowing quartz sand out at high speed with compressed air to clean the surface of parts. It is also called sand blowing in the factory, which not only removes rust, but also removes oil by the way, which is very useful for painting. Commonly used for surface rust removal of parts; Surface modification of parts; In steel structure, it is an advanced method to connect with high-strength bolts. Because the high-strength connection uses the friction between the joint surfaces to transmit force, the quality of the joint surfaces is very high, so the joint surfaces must be sandblasted.
Sand blasting is used for complex shape, easy to remove rust by hand, low efficiency, bad site environment and uneven rust removal. General sandblasting machines have various specifications of sandblasting guns. As long as it's not a particularly small box, you can put the gun in and clean it. The supporting product of pressure vessel-the head is used to remove the oxide scale on the surface of the workpiece by sandblasting, and the diameter of quartz sand is1.5 mm ~ 3.5 mm. One kind of processing is to use water as the carrier to drive emery to process parts, which is a kind of sandblasting processing.
Shot blasting is to use a high-speed rotating impeller to throw small steel shot or small iron shot and hit the surface of the part at high speed, thus removing the oxide layer on the surface of the part. At the same time, the steel shot or iron shot hits the surface of the part at high speed, which causes the lattice distortion on the surface of the part and increases the surface hardness. It is a method to clean the surface of parts, and shot peening is often used to clean the surface of castings or strengthen the surface of parts.
Secondly, let's take a look at the shot blasting machine.
Generally speaking, shot peening is used for regular shapes and the like. And several shots are thrown up and down together, with high efficiency and little pollution. The size of the ball used for shot blasting is 1.5 mm.
The research shows that, as far as damage is concerned, it is much easier when there is tensile stress on the surface of metal materials than when there is compressive stress on the surface, and the fatigue life of materials is greatly improved when there is compressive stress on the surface. Therefore, for parts such as shafts that are prone to fatigue fracture, surface compressive stress is usually formed by shot peening to improve product life. In addition, metal materials are very sensitive to tensile force, which is why the tensile strength of materials is much lower than the compressive strength, which is why metal materials generally use tensile strength to express their properties.
Both shot blasting and sand blasting can clean and purify the workpiece. The purpose is to prepare for the next working procedure, that is, to ensure the roughness requirements of the next working procedure, and to ensure the consistency of the surface. Shot blasting can strengthen the workpiece, so sandblasting is not obvious. Generally, shot peening is a small steel ball, and sand blasting is quartz sand. According to different requirements, itemize. Sand blasting and shot blasting are used in precision casting almost every day. _ tank sandblasting,
Sand blasting and oxidation of aluminum products
What is sandblasting?
1, what is sandblasting? Sandblasting is driven by compressed air to form a high-speed jet beam, which sprays the sprayed material to the surface of the workpiece to be treated at high speed, changing the appearance or shape of the outer surface of the workpiece surface. Because of the impact and cutting action of abrasive on the workpiece surface, the workpiece surface has a certain cleanliness and different roughness, which improves the mechanical properties of the workpiece surface, thus improving the fatigue resistance of the workpiece, increasing its adhesion to the coating, prolonging the durability of the coating, and being beneficial to the leveling and decoration of the coating.
2, the main application scope of sandblasting:
Coating and pretreatment sandblasting can remove all dirt on the surface of the workpiece, establish a very important basic pattern on the surface of the workpiece, and achieve different degrees of roughness by replacing abrasives with different particle sizes, such as flying abrasive, which greatly improves the bonding force between the workpiece and coating and electroplating materials. Or the bonding part is more firmly bonded and the quality is better.
By cleaning, polishing and sandblasting the rough surfaces of the heat-treated castings and workpieces, all dirt on the surfaces of the heat-treated castings and forgings and workpieces can be cleaned, and the surface of the workpieces can be polished to improve the smoothness of the workpieces, so that the workpieces can present uniform metal colors and the appearance of the workpieces is more beautiful.
Burr cleaning and surface beautification sandblasting of machined parts can clean up tiny burrs on the surface of the workpiece, make the surface of the workpiece smoother, eliminate the harm of burrs and improve the grade of the workpiece. Moreover, sandblasting can make a small fillet at the junction of the workpiece surface, which makes the workpiece look more beautiful and precise.
Improve the mechanical properties of parts after sandblasting. Mechanical parts can produce uniform and delicate concave and convex surfaces on the surface of parts, so that lubricating oil can be stored, thus improving lubrication conditions, reducing noise and prolonging the service life of machinery.
Polishing function For some special-purpose workpieces, sandblasting can achieve different reflection or matt at will. For example, the polishing of stainless steel workpieces and plastics, the polishing of jade articles, the extinction of wooden furniture surfaces, the patterns on frosted glass surfaces, and the roughening of cloth surfaces.
3. Matters needing attention in sandblasting work
A. You must wear protective equipment before work, and you are not allowed to work with bare arms. There shall be no less than two people at work.
B, gas storage tank, pressure gauge, safety valve to check regularly. The gas storage tank discharges ash once every two weeks, and the filter in the sand tank is checked once a month.
C, check whether the ventilation pipe and sandblasting machine door are sealed. Five minutes before work, ventilation and dust removal equipment must be started. When the ventilation and dust removal equipment fails, the sandblasting machine is prohibited from working.
D, compressed air valve to open slowly, air pressure is not allowed to exceed 0.8MPa.
E, sandblasting granularity should adapt to the work requirements, generally between 10 and 20, and the sand should be kept dry.
F, sandblasting machine is working, irrelevant personnel are prohibited from approaching. Please stop the machine when cleaning and adjusting the moving parts.
G, are not allowed to use compressed air to blow dust or joking.
H, after the work, ventilation and dust removal equipment should continue to run for five minutes and then shut down to discharge indoor dust and keep the site clean.
4, sandblasting process
Pretreatment stage of sandblasting process
The pretreatment stage of sandblasting process refers to the treatment of workpiece surface before spraying and spraying protective layer.
The quality of pretreatment before sandblasting affects the adhesion, appearance, moisture resistance and corrosion resistance of the coating. If the pretreatment work is not done well, the corrosion will continue to spread under the coating, resulting in the coating falling off in pieces. After careful cleaning of the surface and simple cleaning of the workpiece, the life of the coating is 4-5 times that of the exposure method. There are many methods for surface cleaning, but the most commonly accepted methods are solvent cleaning, acid cleaning, hand tools and electric tools.
Sand blasting stage
Sand blasting technology is driven by compressed air to form a high-speed jet beam, which sprays materials to the surface of the workpiece to be treated at high speed, so that the appearance of the outer surface of the workpiece changes. Due to the impact and cutting action of abrasive on the workpiece surface, the workpiece surface has a certain cleanliness and different roughness, and the mechanical properties of the workpiece surface are improved.
5, the classification of sandblasting machine
Sandblasting machine is the most widely used product of abrasive jet. Sandblasting machines are generally divided into dry sandblasting machines and liquid sandblasting machines, and dry sandblasting machines can be divided into suction type and pressure type.
A, suction dry sandblasting machine
1. General ingredients
A complete suction dry sandblasting machine generally consists of six systems, namely, structural system, medium power system, pipeline system, dust removal system, control system and auxiliary system.
2. Working principle
The suction dry sandblasting machine is powered by compressed air, and the abrasive passes through the sand conveying pipe through the negative pressure formed in the spray gun by the high-speed movement of air flow.
The suction spray gun is sprayed to the machining surface through the nozzle to achieve the expected machining purpose. Compressed air is not the only supply source in the suction dry sandblasting machine.
Second, the press-in dry sandblasting machine
1. General ingredients
A complete press-in dry sandblasting machine generally consists of four systems, namely pressure box, medium power system, pipeline system and control system.
2. The working principle of press-in dry sandblasting machine.
The press-in dry sandblasting machine is powered by compressed air, and the abrasive passes through the sand outlet valve through the working pressure established by the compressed air in the pressure tank.
The pressed sand conveying pipe is sprayed out through the nozzle and sprayed on the machining surface to achieve the expected machining purpose. Compressed air is not the only supply source in the press-in dry sandblasting machine.
Third, the liquid sandblasting machine
Compared with dry sandblasting machine, the biggest feature of liquid sandblasting machine is to control the dust pollution during sandblasting and improve the working environment of sandblasting operation.
1. General ingredients
A complete liquid sandblasting machine generally consists of five systems, namely, structural system, medium power system, pipeline system, control system and auxiliary system.
2. Working principle
The liquid sandblasting machine takes the grinding fluid pump as the power supply of grinding fluid, and delivers the evenly stirred grinding fluid to the spray gun through the grinding fluid pump. As the accelerating power of grinding fluid, compressed air enters the spray gun through the gas pipeline. In the spray gun, compressed air accelerates the grinding fluid entering the spray gun and sprays it to the surface to be machined through the nozzle to achieve the expected machining purpose. In the liquid sandblasting machine, the grinding pump is the feeding power and the compressed air is the accelerating power.
6, sandblasting cleaning level
That is, cleanliness, there are two representative standards in the world: one is "SSPC-"formulated by the United States in 1985; The second is "Sa-" formulated by Sweden in 1976, which is divided into four grades, namely Sa 1, Sa2, Sa2.5 and Sa3, and is an international standard. Details are as follows:
Sa 1- is equivalent to SSPC-SP7 in the United States. Generally, simple hand brushing and sanding methods are adopted, which is the lowest level among the four cleanliness, and the protective property of the coating is only slightly better than that of untreated workpieces. Sa 1 class treatment technical standard: the surface of the workpiece should be free of dirt such as oil stain, grease, residual scale, rust stain and paint residue. Sa 1 level is also called manual scrubbing and cleaning level.
Sa2- equivalent to SSPC-SP6 in the United States. Sand blasting cleaning method is the lowest level of sand blasting treatment, which is a general requirement, but the protection of coating is much higher than manual brushing. Technical standard for Sa2-level treatment: the surface of the workpiece should be free of foreign bodies such as oil stain, scale, rust, paint, oxide, corrosion, etc., but the defects should be limited to no more than 33% of the surface per square meter, and there may be slight shadows; Slight discoloration caused by defects and corrosion; Scale and paint defects. If the original surface of the workpiece has dents, slight corrosion and paint will remain at the bottom of the dents. Sa2 level is also called commodity cleaning level.
Sa2.5 level-it is a commonly used level in industry and can be used as the technical requirements and standards for acceptance. Sa2.5 level is also called near white cleaning level. Sa2.5 treatment technical standard: the same as the first half of Sa2, but the defects are limited to no more than 5% of the surface per square meter, which may include slight shadows; Slight discoloration caused by defects and corrosion; Scale and paint defects.
Sa3 grade is equivalent to SSPC—SP5 grade in the United States, and it is the highest treatment grade in the industry, also known as white cleaning grade. Technical standard of Sa3 treatment: same as Sa2.5, but there must be 5% shadow, defect and rust.