1.Using chicken feathers or matches to check the air leakage at the welding place of the drying equipment. You can use chicken feathers to approach the inspection place. If there is any air leakage, the chicken feather will be absorbed in the gaps on the surface of the equipment.
2.Lighting a match and move it close to the surface of the device, and air leakage will be quickly found. Larger air leakage can be judged of there is hiss noise.
3.Dipping some water in your hand and touch it. Negative pressure air leakage means that the wind flows from the outside to the system. You can let your hand close to the wall and the surface of the device. If there is air leakage, it will feel like being sucked by the cool air. The air leakage is easier to feel because the hand is wet.