Leak testing machine for drum, also known as leak tester or leak checking machine, is mainly used for automobile, internal combustion engine, motorcycle, compressor and other industries as an important equipment testing leakage of parts and guaranteeing product quality. In order to guarantee that the vent cap for drum equipment meets operating requirements of demander (anti-seep,air permeability, chemical resistance, etc. ), the demander must test adaptability of vent cap before volume production.