The cooled solid carbon dioxide is dry ice. Carbon dioxide is non-toxic, and at -78.5°C under normal pressure, dry ice absorbs heat and sublimates into carbon dioxide gas. Dry ice blasting technology is to mix dry ice pellets with high-speed flowing compressed air. A cleaning method in which the dirt on the surface of the object to be cleaned is broken by the nozzle of the spray gun at low temperature, and finally stratified by impact peeling.

The dry ice blasting method is dry decontamination. After dry ice blasting, it evaporates instantly, leaving no residue and no secondary waste. It can be directly decontaminated on the production line without affecting production. Compared with sandblasting, the impact force is small, it is non-destructive decontamination, and does not damage equipment or abrasives.

Impact force: The dry ice hits the clean surface at high speed, the dissipation of the kinetic energy of the impact and the extremely fast heat transfer between the dry ice particles and the clean surface make the carbon dioxide change from solid to gas instantly. "Micro-explosion": dry ice particles (powder) enter the gaps of the dirt, evaporate within a few thousandths of a second, and the volume expands nearly 800 times in an instant, which is the air lift effect, thereby taking the dirt away from the surface of the object. "Cracking": Two different materials have different thermal expansion coefficients, and the temperature difference between them will destroy the bond between the two materials. The temperature of dry ice particles is extremely low. After hitting the surface of the object to be treated, the dirt will be frozen until it becomes brittle and burst, resulting in "cracking" or thermal shock, which affects the mechanical properties of the attached dirt and is easy to remove.

Advantages of dry ice blasting: 1. Cost saving, dry ice is directly volatilized during the cleaning process, and there is no cost for cleaning secondary pollution. 2. Improve efficiency, clean on-line, save a lot of downtime, do not need to increase labor and production equipment, increase production and efficiency. 3. Extend the service life of the equipment. Unlike abrasives such as sand, walnut shells, plastic pellets, etc., dry ice pellets are not abrasive. Dry ice blasting will not damage molds, tolerances, bearings and machines. In addition, cleaning in place avoids accidental damage to molds during disassembly and assembly. 4. Dry cleaning process, unlike steam and high-pressure water cleaning, dry ice cleaning has no damage to circuits, control components and switches. Compared with water cleaning, the possibility of equipment rusting after cleaning is greatly reduced. 5. Environmental protection and safety. Carbon dioxide is a non-toxic substance, and by using dry ice instead of toxic chemicals, employees can essentially avoid chemical hazards. Since carbon dioxide is heavier than air, ventilation and safety must be ensured when performing dry ice blasting in confined spaces or recesses. 6. Reduce labor intensity, reduce labor intensity of workers, avoid the hazards of chemical agents, and reduce the risk of occupational diseases.