What is the method for vehicle air tightness testing?
2 Answers
Testing is conducted using air tightness leak detection equipment. Additional information on air tightness is as follows: 1. Compressibility: Gas is compressible and has low viscosity, which is negligible. This means that air passes through leaks 100 to 400 times faster than liquids. Gas inherently lacks surface tension, making it easier to pass through small leaks compared to liquids. 2. Leakage: Leaks that allow gas to pass may not necessarily allow liquids to leak. This is why, when using air as the medium for leak testing, an allowable air leakage rate must be defined. Detecting leaks ensures the product's sealing and waterproof performance, as long as the air leakage remains within the permissible range. Air leakage does not necessarily mean water or oil leakage, which in such cases achieves the desired sealing, waterproofing, and leakage control effect.
I think the vehicle air tightness test is mainly done using the air pressure method, which is quite practical. The specific steps are to close all doors and windows tightly, then install a dedicated blower inside the car to pressurize it, creating a high-pressure internal environment. Then, use a pressure gauge to monitor the pressure. If the pressure drops rapidly, it indicates air leakage points, such as around door gaps or window edges where issues commonly occur. You can also spray water on the outside to help locate the leaks, as water seeping in will make them obvious. The test results need to be recorded and analyzed to ensure the sealing effect meets standards, especially before the rainy season to prevent leaks. This test can improve in-car comfort and reduce noise infiltration. It’s good to perform regular checks during routine maintenance, and I often use this method to help friends fix minor issues.
