Aeration perforated diaphragm There are two main ways: laser drilling and drilling machinery. Laser drilling through the laser irradiation, the surface of the film to burn a small hole. The disadvantage is lossy material, and the peripheral portion of the rubber hole has gone bad, closing poor performance in foreign basically not used. Mechanical drilling, with precision tools, the cut surface of the film, the general should be non-destructive material, so that when the drums of gas, the hole open, not when the aeration holes automatically closed, preventing the leak back.