Automatic barrel loading is realized by a simple mechanical arm (driven by air cylinder): When the photoelectric sensor detects the barrels conveyed from the external barrel brushing machine via the conveyor chain, the mechanical arm starts to operate and automatically transfers the barrels from the conveyor chain to the barrel loader. The overturning air cylinder then activates to move the empty barrels to the inner barrel rinsing machine. This system is equipped with a barrel loading and positioning device to prevent improper barrel insertion and achieve a 100% barrel loading rate.