Information reference comes from：SGS TAIWAN
Instruction
Cleanliness of components and parts is a necessary method in monitoring the quality of production process and final products, especially in automotive, aerospace, semiconductor industries.
Particle contaminants of different sizes can cause equipment to wear out, fail, block, fail, and get out of control. Corrosive chemical contamination: rusting of metal parts and products, aggressive atomization of optical components, short circuits to electronic circuits. Settling chemical pollution: interference with telecommunications strength, signal distortion and signal anomalies, circuit impedance anomalies, product overheating, adhesion failure, optical component adhesion atomization. Those industries require cleanliness testing . As long as it is a precision process industry and by trace pollution easy to cause adverse products industry Whether from the beginning of the original material to the production environment and the equipment used Personnel to the final packaging material storage and transportation Strict controls on cleanliness are required
- Photoelectric & semiconductor
- Automation equipment
- Precision machinery
- Medical equipment
- Automotive industry
- Printed circuit board
- Hard drive components
- Clean room supplies
Cleanliness refers to the degree to which a particular part of a part, assembly, and machine is contaminated with impurities, and represents the amount of contaminants that remain on the surface of a part or product after cleaning, expressed by the value of the quality, size and quantity of impurity particles collected from a specific site by prescribed methods.
Specific parts are features that endanger product reliability, such as automotive functional components, including fuel systems, oil circuit cycles, braking systems, cooling system cycles, hydraulic systems and air conditioning systems. Hydraulic components and systems are particularly sensitive to the presence of particulate matter. Contaminates exist in the process of manufacturing, transportation, and natural environment. The surface contaminates, such as particles and non-volatile residues (NVR), have a direct effect on function, reliability, and even service life of final products. As a result, there’s corresponding cleanliness inspection standards in each industry, such as ISO 16232 and VDA 19.1 in automotive industry.
Cleanliness testing uses extraction method, including agitation, pressure rinsing, ultrasonic techniques, to remove the residues from parts. Then isolate the contaminates or particulates from collected fluid (i.e., washing liquid) by filtration, followed by particular analysis methods, such as mass, sizing, counting, and morphological characterization, according to product characteristics and cleanliness requirements. Verifying cleanliness during or after manufacturing can prevent potential product failures in the field or shorten the service life.
Method
Cleanliness testing was first used in the aerospace industry, and in the early 1960s the American Society of Automotive Engineers (SAE) and the American Aerospace Industry Association (AIA) began using uniform cleanliness standards. The German Association of Automobile Manufacturers released the Standard for Particle Cleanliness Testing (VDA 19) in March 2015, while the international standard for cleanliness of automotive components, ISO-16232, is currently a broader method of application. Other industries have also set different cleanliness specifications for the process requirements of their products, such as printed circuit boards (IPC-TM650), cleanroom supplies (IEST-RP), cleanrooms (ISO-14644), compressed air (ISO-8573).
Washing / extraction → filtration → drying → weighing → analysis → microscopic examination results
Generally, the washing liquid are often aqueous fluids and organic solvents, e.g., dichloroethane and ethanol, with surfactants. Consequently, a chemical resistant vacuum pump is recommended to accelerate the filtration process with the aid of vacuum and reduce the pump corrosion by chemical vapors as well.
ISO 16232 Standard for Components and Parts Cleanliness
There are lots of inspection entity such as SGS provides cleanliness testing of various components, allowing quickly meet international standards for automotive industry, precision machinery, and electronic semiconductor components suppliers.
These pollutions will affect the components and structural functions, and then affect the service life and reliability of the entire system. According to ISO 16232:2018, this regulation applies to the scope of application of various components in contact with fluids, and the definition of fluids, such as: gasoline, fuel, air-conditioning, refrigerant, coolant, solid lubricating oil… etc. In the assembly stage, control the total number of component particles to meet the requirements of ISO 16232 for component and system reliability.
Applications
- Electronics testing, such as PCB and semiconductor.
- Parts testing in automobile and electric vehicle.
- Machinery components testing, such as medical device
