Laser cleaning technology is an emerging green cleaning technology in recent years. As far as its mechanism for mold cleaning is concerned, it uses the mold matrix and surface attachments to have a large difference in the energy absorption of a certain laser wavelength, radiating to the surface. Most of the laser energy is absorbed by the surface attachment, causing it to be heated, vaporized, evaporated, or expanded instantly. It is driven by the vapor flow formed on the surface and separated from the surface of the object to achieve the purpose of cleaning. The advantage of laser cleaning over dry ice cleaning is that the cleaning process is low-cost and can remove dirt of various thicknesses and compositions. The cleaning process is easy to realize automatic control and long-distance remote control cleaning, and there is no secondary consumption in the cleaning process.
1. Application of laser cleaning technology in the field of tire molds
The mold is an important tool used in the tire vulcanization production process. During the use of the tire mold, it is polluted by the comprehensive deposition of rubber, compounding agents, and release agents. Problems such as carbon deposits, adhesives, and difficulty in de-molding will inevitably occur. The pattern contaminates the dead zone. A clean mold is crucial to obtain high-quality products. The mold must be cleaned frequently to maintain its surface cleanliness to ensure the life of the mold and tire quality.
Commonly used cleaning methods for tire molds mainly include mechanical, chemical, ultrasonic, and dry ice cleaning. Although these cleaning methods are widely used in the cleaning industry, their applications are greatly limited under online high-precision automated cleaning requirements. Compared with other cleaning methods, dry ice cleaning has unique technical advantages in the field of tire molds and has become the current mainstream method of mold cleaning. However, dry ice is a chemical product, and the preparation and transportation of raw materials are difficult, secondary consumption is large, and cleaning costs are relatively high.
2. Application of laser cleaning technology in the field of silent tire inner wall cleaning
New energy vehicles are quieter than conventional internal combustion engine vehicles, and the development of new energy vehicles has also put forward stricter requirements for tire noise control. New energy vehicle tires can better adapt to the needs of new scenarios by improving the rubber formula, tire aspect ratio, tire volume, tread material, tread pattern, etc.
As a "green" cleaning process, laser cleaning technology has a good application in the silent tire manufacturing process. It uses a focused high-energy laser beam to irradiate the surface of organic polymer materials, causing physical and chemical changes on the surface of the material, thereby changing its surface. performance. It can effectively improve tire quality and production technology, improve the matching between tires and car bodies, and improve the overall performance of the vehicle. By coating the inner wall of the tire with a soft solid gel-like polymer composite material, the explosion-proof, anti-puncture, and anti-leakage functions are achieved. At the same time, a layer of polyurethane sponge is pasted on the surface of the anti-leakage rubber to achieve sound insulation and heat insulation, and a silent effect of absorbing cavity noise.
Laser cleaning can effectively remove the residual release agent on the inner wall of the tire, and improve the coating of composite materials and the adhesion of polyurethane sponge. The cleaning process requires no consumables, no damage to the tires, high efficiency and good consistency, and can realize automated cleaning.
By selecting pulse laser equipment and formulating a reasonable process flow, the samples are evaluated. Through the dyne pen test, the surface tension values under different parameters are obtained. The results show that different process parameters (laser energy density, processing efficiency) will affect the surface tension of the inner wall of the tire. The process parameters must be reasonably formulated for the production process of silent tires. Throughout the test, the laser cleaning was uniform and the damage to the substrate was far beyond the requirements.
The use of a laser to clean the inner wall of the tire requires no consumables, no damage to the tire, fast cleaning speed, and good quality consistency. It can realize automatic cleaning and does not require the subsequent chip removal operation of traditional grinding and the subsequent blow-drying operation process of wet cleaning. Laser cleaning has no pollutant emissions and is ready for use, making high-quality preparations for the subsequent bonding of silent tires, self-repairing tires, and self-detection functional tires.
3. Application of laser cleaning technology in the field of tire rubber texturing
At present, with the continuous development of our country's economy, the scale of development of cars, trucks, etc. is also constantly expanding, which has led to an active increase in the number of tire replacements, which has led to a large increase in the amount of discarded tires. If the scraps are discarded directly Tires not only cause a waste of resources but also pollute the environment. Many of the used tires being replaced are tires that are in good basic condition and can still be used after retreading.
Traditionally, the process of re-vulcanizing only the tread is called tire retreading. Depending on the degree of tire damage, top-turn, shoulder-turn, or full-turn processes are used for retreading. The traditional method of tire retreading is to stick the mixed adhesive to the filed tire carcass, then place it into a steel mold of a fixed size, and undergo a vulcanization process at a temperature of over 150°C, commonly known as "hot retreading", or hot retreading. vulcanization method.
Before retreading, the cleaned tire tread needs to be polished to a thread-like rough state. The effect of increasing the roughness through grinding is uneven and can easily cause holes, which is not conducive to the subsequent vulcanization combination of the carcass and the tread so the quality of the retreaded tire product does not meet the standard.
Laser cleaning can evenly create lattice-shaped pits to achieve texturing on the tire rubber surface. A pulse laser cleaning machine using a Gaussian spot controls the galvanometer to perform horizontal and vertical laser scanning respectively. Through appropriate process parameters, the roughness of the tire rubber surface can be uniformly increased and the bond between the vulcanized carcass and the tread can be enhanced. Combined forces for higher quality tire retreading.