Szacowany czas czytania: 8 minuty
Traditional industrial cleaning methods include mechanical cleaning, chemical cleaning, and ultrasonic cleaning. Mechanical cleaning uses scraping, wiping, brushing, sandblasting and other mechanical means to remove surface dirt; wet chemical cleaning uses organic The ultrasonic cleaning method removes the surface adhering property by spraying, showering, soaking, or high-frequency vibration and other measures to put the processed parts into the cleaning agent and use the vibration effect generated by ultrasonic waves to remove the dirt.
At present, these cleaning methods still dominate the cleaning market in my country, but their application is greatly restricted under the requirements of environmental protection and high precision. The mechanical cleaning method cannot meet the requirements of high cleanliness cleaning, and it is easy to damage the surface area of the workpiece to be cleaned, while the chemical cleaning method is easy to cause environmental pollution, and the cleanliness obtained is also very limited, especially when the dirt composition is complex, it is necessary to choose a variety of cleaning agents repeatedly. Only cleaning can meet the requirements of surface cleanliness. Although the ultrasonic cleaning method has a good cleaning effect, it is powerless to clean the sub-micron dirt particles. The size of the cleaning tank limits the scope and complexity of the processed parts, and the drying of the workpiece after cleaning is also a big problem. Ultrasonic cleaning of molds can negatively impact mold production because the process is time-consuming and some molds need to be disassembled for cleaning. Also, this process can only be used with cooled molds. The production of a new round can only be restarted after the mold is cooled, cleaned, and heated again, which is time-consuming and labor-intensive.
In recent years, the enhancement of people’s awareness of environmental protection has brought huge challenges to the development of the cleaning industry around the world. Various cleaning technologies that are conducive to environmental protection have emerged as the times require, and laser cleaning technology is one of them. The so-called laser cleaning technology refers to the use of high-energy laser beams to irradiate the surface of the workpiece to instantly evaporate or peel off the dirt, rust spots, or coatings on the surface, and effectively remove the surface attachments or surface coatings of the cleaning object at high speed, so as to achieve a clean process.
The Principle And Characteristics of Laser Cleaning
1. No grinding and non-contact cleaning to avoid secondary pollution;
2. High cleaning precision, strong controllability, and remote cleaning;
3. No consumables, strong environmental protection, does not damage the health of operators;
4. Laser cleaning can remove different types and thicknesses of attachments on the surface of various materials;
5. Easy to control, just power on, can be hand-held or cooperate with the manipulator to realize automatic cleaning;
6. High cleaning efficiency, saving time;
7. The system is stable and has a long service life;
8. One-time investment, economical and efficient.
Application Status of Laser Cleaning
Due to its extremely fine and fragile surface structure, high-end stone artworks such as stone carvings and stone carvings have become the earliest fields of application of laser cleaning technology. It has been found that the use of lasers to remove dirt on the surface of stone cultural relics has its unique advantages. It can control the movement of the light beam on complex surfaces very precisely to remove dirt without damaging the cultural relics.
Application of Laser Cleaning in Tire Molds
After laser cleaning of the stone sculpture collection in ins rentier, one of the most important stone sculpture collections in the UK, people observed the surface of the stone sculpture after laser cleaning with an electron microscope. They found that the structure of the stone did not change after laser cleaning. The surface is smooth and flat with no damage. This is completely different from a surface cleaned by micro-particle blasting (sandblasting). The damage to the marble surface structure after the micro-particle jet cleaning is unavoidable, especially for the marble surface with the existing sulfate scale layer. Electron microscope observation also found that after laser irradiation, the properties of the subsurface rock materials were neither degraded nor changed.
Laser cleaning of limestone, marble, and other high-grade stone materials has become a new and promising business project. In addition to the cleaning of stone materials, laser cleaning has a good effect on the cleaning of glass, metal, molds, disks, and various microelectronic products. In the production of automobile tires, the bottom and surrounding patterns of tire molds are It needs to be cleaned every two to three weeks, and the entire mold needs to be thoroughly cleaned every few months. The traditional method is to use chemical liquid to soak or sandblast cleaning, which is not only expensive, noisy, and polluted but also affects the surface quality of the mold.
In addition, this type of cleaning method cannot realize online cleaning, and the disassembly of the mold before cleaning and the installation of the mold after cleaning takes a long time, which affects the normal operation of the production line. Using laser technology to clean molds can realize online cleaning operations. Depending on the number of organic deposits on the mold’s surface and the rubber compound’s structure, it only takes 45-90 minutes to clean a set of molds (including loading and unloading and cleaning the parts on both sides of the mold). Since the mold surface can reflect the laser beam, the mold surface will not be damaged by the laser. Laser cleaning is highly flexible, and users can use this technology to replace other methods in use. At present, YAG lasers have been used abroad to realize online cleaning of tire molds on tire production lines, and have been applied to the industry. When the mold needs to be cleaned, turn on the vulcanization at the same time as the vulcanization is over, and move the laser mold cleaning system to the vulcanized to clean the mold without waiting for the mold to cool.
The time to clean the mold has nothing to do with the temperature of the mold. The operator places the head of the laser cleaning system against the mold to start cleaning. During the cleaning process, the laser beam scans the mold surface and irradiates the mold surface from four different angles, which ensures that all types of molds can be cleaned. After one-half of the cleaning is done, move the head of the washer to the other half of the mold for cleaning. After the mold is completely cleaned, move the cleaning device to another vulcanized mold to be cleaned. The cleaned vulcanized can be put into production immediately. In addition to cleaning molds, industrial applications include marking tires, removing coatings from parts such as brake wires, or stripping wires from flat conductors.
At present, YAG lasers have been used abroad to realize online cleaning of tire molds on tire production lines, and have been applied to the industry. If the system runs at full capacity, the production time can be saved by 6,000 hours based on the original tire factory cleaning 1,500 pairs of molds a year; the tire output can be increased by about 30,000 sets. Not only environmental protection but also considerable economic benefits.
The application of laser cleaning technology has been popularized and applied in Europe for several years, and there are already products, but my country has only just started, and there is still some difficulty in general application. Compared with traditional cleaning technology, laser cleaning technology has incomparable advantages. At present, the high-efficiency and low-cost cleaning method of tire molds urgently need to be promoted. According to incomplete statistics, there are thousands of tire and product manufacturers in my country, and there are no less than 2,000 enterprises with an annual output of more than one million sets of tires. Manufacturers with an annual output of one million sets of tires have tens of thousands of molds, and a mold needs to be cleaned every three weeks. It can be seen that the promotion and application of laser technology cleaning are of great significance. It is believed that on the basis of the continuous improvement of this technology, with the mass production of equipment, laser cleaning technology will play an important role in tire mold cleaning or other cleaning industries, and has a good development prospect.
The repair and maintenance costs of the laser cleaning equipment should also be included. In order to clean the laser mirror and remove the residue deposited on the filter, the unit needs to be maintained for 30 minutes per week and the main components for 60 minutes every 4 weeks. Routine maintenance of the unit and operation of the laser system are performed every 6 months per the manufacturer’s requirements. Most of the mechanical parts can have a service life of more than 10 years like the laser frame, and some laser parts require replacement after about 300 hours of use. These parts are field replaceable during routine preventive maintenance. Laser unit plus its one-year warranty. Including the replacement of consumable parts and providing typical spare parts, the total operating cost is about $4-8 per hour. All equipment has a Modem (modulator) installed so the manufacturer can provide remote service.