The air-tightness tester and the leak-tightness tester are first and foremost equipments to detect the product for leaks. The air tightness tester is mainly used to detect workpieces such as: pressure vessels, valves and fittings. The sealing performance test is mainly used to test the sealing performance of the product packaging bags, boxes, bottles, cans, etc. Secondly, the gas tightness detection medium is gas, and the sealing performance detection can be either gas or liquid.

The air tightness tester and the air tightness tester can be classified as follows according to the testing principle: 1. Positive pressure method air tightness test: adopt positive pressure inflation principle. 2. Negative pressure method air tightness detection: the principle of vacuum test is adopted.