The traditional cleaning industry has various cleaning methods, most of which are cleaned by chemical agents and mechanical methods. In my country, the requirements of environmental protection regulations are getting higher and higher, and people's awareness of environmental protection and safety is getting higher and higher today, the types of chemicals that can be used for industrial production cleaning will become less and less.
How to find a cleaner and more non-destructive cleaning method is a problem we must think about. Laser cleaning has the characteristics of no grinding, no contact, no thermal effect, and is suitable for objects of various materials, and is considered to be the most reliable and effective solution. At the same time, laser cleaning can solve problems that cannot be solved by traditional cleaning methods.
The physics of laser cleaning
The light emitted by the laser is absorbed by the contamination layer on the surface to be treated. Larger energy absorptions rapidly expand to form plasmas (highly ionized unstable gases), creating shock waves. The shock wave removes contaminants through the debris.
Compared with traditional cleaning methods, such as mechanical friction cleaning, chemical corrosion cleaning, liquid solid strong impact cleaning, high-frequency ultrasonic cleaning, etc., laser cleaning has five obvious advantages.
The benefits of environmental protection: Laser cleaning is a "green" cleaning method that does not require any chemicals and cleaning solutions. The cleaned waste is basically solid powder, small in size, easy to store, recyclable, free of photochemical reaction, and non-polluting. It can easily solve the problem of environmental pollution caused by chemical cleaning. In most cases, an extractor fan can solve the problem of cleaning waste.
Effect advantage: The traditional cleaning methods are mostly contact cleaning. The surface of the cleaned object is affected by mechanical force, which will damage the surface of the object. The cleaned medium adheres to the surface of the cleaned object and cannot be removed, resulting in secondary pollution. The non-abrasive and non-contact, non-thermal effects of laser cleaning solve these problems without damaging the substrate.
Control advantages: The laser can be transmitted through the optical fiber, cooperate with the manipulator and the robot, can easily realize the remote operation, and clean the parts that are difficult to reach by traditional methods, which can ensure the safety of the personnel.
Advantages of convenience: Laser cleaning can remove various contaminants on the surface of various materials and achieve cleanliness that cannot be achieved by conventional cleaning. In addition, contaminants on the surface of the material can also be selectively cleaned without damaging the surface of the material.
Cost advantage: Laser cleaning is fast, efficient, and time-saving; the initial investment of laser cleaning system is high, but the cleaning system can be used stably for a long time, the operating cost is low, and more importantly, it can be easily automated. Cost calculation: One cleaning efficiency is 8 square meters, and the operating cost per hour is about 5 degrees. That is, the cleaning cost is 4 cents/square meter, and after removing the initial cost, it is 4 cents/square meter in the later period.
The use of laser cleaning in various fields
Laser cleaning technology is a new cleaning technology that has developed rapidly in the past ten years. It has replaced traditional cleaning technology in many fields with its own advantages and irreplaceability. Laser cleaning can not only clean organic pollutants, but also clean metal raw materials. Inorganic substances such as rust, metal particles, dust, etc. Several practical applications are introduced. These technologies are very mature and widely used.
1. Cleaning of the mold
Every year, tire manufacturers around the world manufacture hundreds of millions of tires, and tire mold cleaning in production must be fast and reliable, saving downtime. Traditional cleaning methods include sandblasting, ultrasonic wave, carbon dioxide cleaning, etc., but these methods usually require the high-heat mold to be cooled for several hours and then moved to the cleaning equipment for cleaning. Cleaning takes time and easily damages the accuracy of the mold. Chemical solvents and Noise also creates safety and environmental protection issues.
The technology of laser cleaning tire molds has been widely used in the tire industry in Europe and America. Although the initial investment cost is high, the benefits obtained by saving standby time, avoiding mold damage, operating safety, and saving raw materials will be quickly recovered.
In the laser cleaning method, the laser can be transmitted through the optical fiber, so it is flexible when used; the laser cleaning method is connected by the optical fiber, and the light guide can be cleaned to the dead corner of the mold and the place that is difficult to remove, which is easy to use; the rubber is not vaporized, so it will not Toxic gas is produced, which affects the safety of the working environment.
2. Cleaning of weapons and equipment
Laser cleaning technology is widely used in the maintenance of weapons. The laser cleaning system can effectively and quickly remove rust and contaminants, and the removal part can be selected to automate the cleaning. Using laser cleaning, not only the cleaning degree is higher than that of chemical cleaning process, but also almost no damage to the surface of the object.
By setting different parameters, a dense oxide protective film and metal melting layer can also be formed on the surface of metal objects to improve surface strength and corrosion resistance. The waste removed by the laser hardly pollutes the environment, and it can also be operated remotely, which effectively reduces the health hazards to workers.
3. Cleaning of old aircraft paint
Laser cleaning systems in Europe have been used in the aviation industry. Aircraft surfaces must be repainted after a certain period of time, but the original old paint needs to be completely removed before painting. The traditional mechanical paint removal method is easy to damage the metal surface of the aircraft, which brings danger to the safe flight. Using multiple sets of laser cleaning systems, the paint layer on the surface of an A320 Airbus can be completely removed within two days without causing damage to the metal surface.
4. Cleaning of building exterior walls
With the rapid development of my country's economy, more and more skyscrapers have been built, and the cleaning problem of the exterior walls of buildings has become increasingly prominent. The laser cleaning system provides an excellent solution for building exterior wall cleaning through optical fibers, which can effectively clean various pollutants on various stone, metal, and glass, and is many times more efficient than conventional cleaning. It can also remove blackening and stains of various stone materials in buildings.
5. Cleaning in the electronics industry
The electronics industry uses lasers to remove oxides: The electronics industry requires high-precision removal of dirt, which is especially suitable for laser removal of oxides. Before soldering to the substrate, the pins of the part must be completely deoxidized to ensure optimal electrical contact, the pins must not be damaged during the decontamination process. Laser cleaning can meet the requirements of use and has high efficiency. It only needs to irradiate the laser once to one pin.
6. Precise deesterification cleaning in precision instrument industry
In the precision machinery industry, in order to lubricate and prevent corrosion of parts, most of the esters and mineral oils need to be removed, usually chemical methods, but residues are often left in chemical cleaning. Laser deesterification completely removes esters and mineral oils without damaging the surface of the part. The removal of contaminants is carried out by shock waves, and the explosive gasification of the thin oxide layer on the surface of the parts forms a shock wave, which leads to the removal of contaminants, rather than mechanical interaction. The deesterification is thoroughly used for the cleaning of mechanical parts in the aerospace industry. Laser cleaning can also be used for oil and ester removal in the machining of mechanical parts.
Introduction to the application prospect of laser cleaning equipment
7. Pipe cleaning in nuclear power plant reactor
The laser cleaning system is also used in the cleaning of the piping in the reactor of the nuclear power plant. Using optical fiber, the high-power laser beam is introduced into the interior of the nuclear reactor to directly remove the radioactive dust and facilitate the cleaning of the material. In addition, because it is operated remotely, the safety of the staff can be ensured.
8. The application of laser cleaning in military equipment: such as paint detachment and rust removal of various aircraft, rust removal of various ship equipment, various weapons and equipment, rust removal of various tank guns, etc., with broad prospects and potential development trends huge. In particular, laser cleaning has obvious advantages such as environmental protection, convenience, safety, and low-cost use. It is a new, efficient and safe process technology.
As mentioned above, laser cleaning plays an important role in many fields, in automobile manufacturing, semiconductor wafer cleaning, precision parts processing and manufacturing, military equipment cleaning, building exterior wall cleaning, cultural relics protection, substrate cleaning, precision parts processing and manufacturing, liquid crystal Areas such as monitor cleaning, chewing gum trace removal, etc. can play an important role.
