The key points for testing the sealing performance of transfer Windows revolve around the core of “no leakage and stable pressure difference”, covering three major links: preparation, testing and judgment. Specifically, they are as follows:
I. Preparations Before Testing
Environmental requirements: The cleanliness of the detection area shall not be lower than that of the usage environment of the transfer window, and there shall be no obvious air flow interference (wind speed ≤0.2m/s).
Equipment calibration: The pressure gauge, soap liquid detector, dust particle counter and other equipment must be within their validity period and meet the accuracy requirements (the error of the pressure gauge is ≤±2Pa).
Transfer window status: Close all door bodies and lock them, ensuring that the sealing strips are undamaged, installed properly, and the interior is clear and unobstructed.
Ii. Core Testing Items
Pressure attenuation method detection: Pressurize the transfer window to 500Pa, then start timing after the gas source is turned off. The pressure attenuation value within 30 minutes should be ≤50Pa (there may be differences among different standards, so follow the usage scenario).
Leakage point detection: Evenly apply soap solution to the gaps of the door body, the interface of the frame, and around the observation window. After pressurizing, observe whether bubbles are produced. If there are no continuous bubbles, it is qualified.
Dust particle verification: Set up sampling points on the side of the transfer window (5cm away from the gap), turn on the purification system of the clean room, and detect the particle count (≥0.5μm), which should have no significant difference from the particle count in the background of the clean room.
Iii. Judgment and Recording
Qualification standards: No visible leakage, pressure attenuation meets the standard, and the number of particles is normal. If all three are satisfied, the seal is qualified.
Record requirements: Provide detailed records of the testing date, equipment model, pressure data, leakage conditions, and testing personnel for easy traceability.
