Cleaning encompasses the process of removing minute dirt particles from mechanical parts, electronic components, optical elements, and more during industrial production.

Ultrasonic cleaning machines can also be categorized into physical and chemical cleaning methods based on the cleaning process: utilizing principles of mechanics, acoustics, optics, electricity, and thermodynamics, relying on external energy sources such as mechanical friction, ultrasonic waves, vacuum, and high pressure. During a strike, methods like ultraviolet light and steam that remove surface dirt from objects are referred to as physical cleaning; using chemicals or solvents to clear surface dirt based on chemical reactions is known as chemical cleaning. For instance, various inorganic or organic acids can be used to remove rust and scale from surfaces, oxidizers to remove stains, and disinfectants to kill microorganisms and remove mold. Physical and chemical cleaning each have their own advantages and disadvantages, offering a good complementarity. In practical applications, they are often combined to achieve better cleaning results.

Based on the type of cleaning medium, it can be divided into wet cleaning and dry cleaning: cleaning in liquid mediums is generally referred to as wet cleaning, while cleaning in gas mediums is known as dry cleaning. Traditional cleaning methods are mostly wet cleaning, and dry cleaning is more commonly associated with vacuum cleaners. However, in recent years, the dry cleaning industry has seen rapid growth, with advancements in technologies like laser cleaning, ultraviolet cleaning, plasma cleaning, and dry ice cleaning, all experiencing rapid development in the high-precision industrial technology sector.