Method for cleaning electronic components with anti-static esd brushes
I. Preparation before operation
Personal protection: Operators need to wear anti-static wrist straps, anti-static work clothes and other equipment to ensure that the human body is at the same potential as the earth to avoid static electricity from damaging electronic components.
Environmental control: Keep the humidity in the working area at 40%-60%, which can be adjusted by a humidifier or a basin to reduce the risk of static electricity.
Tool inspection: Confirm that the surface resistivity of the U-shaped anti-static brush meets the requirements (usually 10³-10⁹Ω/□), and the bristles are not broken, deformed or contaminated.
II. Tool selection and adaptation
Size matching:
Small U-shaped brush (5 rows of bristles, 50 bundles of bristles): suitable for cleaning fine components (such as BGA chips) and narrow gaps.
Medium/large U-shaped brush (7 rows/8 rows of bristles, 98 bundles/160 bundles of bristles): used for fast cleaning of large-area PCB boards or dense components.
Material adaptation: Hard brush (conductive PA fiber): remove stubborn dirt or oxides, such as solder slag on circuit boards. Soft brush (nylon or animal hair): clean the surface of sensitive components (such as capacitors, IC pins) to avoid scratches. 3. Cleaning operation process Preliminary cleaning: Use a U-shaped brush to sweep along the surface of the PCB in one direction to remove loose dust and debris, and be careful to avoid fragile components. For multi-layer boards or dense areas, a blowing tool can be used to assist in dust removal. Detail processing: Use the elbow design of the U-shaped brush to penetrate into the gap between components (such as the bottom of the connector and between the chip pins) and remove stubborn stains with a small vibration. For oxides or slight corrosion, a small amount of anti-static solvent (such as isopropyl alcohol) can be used for local wiping. After completion, use a dry brush to absorb the residual liquid immediately. Final inspection: Use a magnifying glass or microscope to confirm the cleaning effect, focusing on key areas such as solder joints and pins. After cleaning, the PCB board needs to be left to stand for 1-2 minutes to ensure that the static electricity is completely dissipated.
IV. Precautions
Force control: Avoid pressing hard to cause the bristles to deform or the components to fall off, and limit the natural bending of the bristles.
Direction specification: Always clean in the same direction, and do not rub back and forth to prevent secondary accumulation of static electricity.
Tool maintenance:
Regularly clean the bristles with anti-static cleaner, and measure the surface resistivity after drying in the shade.
Replace the bristles when they are worn more than 30% or the resistance value exceeds the standard.
V. Typical application scenario examples
PCB board maintenance: The U-shaped brush with a crank structure can clean the SMD components on the back of the graphics card/motherboard, and the efficiency is more than 50% higher than that of the straight handle brush.
BGA rework: A small U-shaped brush with a hot air gun can remove solder ball residues without damaging the substrate.
(Note: The above method is a comprehensive standardized operating procedure in the field of electronic manufacturing and maintenance)