A small valve or faucet used to drain or reduce pressure, as from a boiler.
A small valve or faucet used to drain or reduce pressure, as from a boiler.
泄气阀，小龙头用来排空或降低压力的一种小阀门或小龙头，如锅炉上的
A small valve or faucet used to drain or reduce pressure, as from a boiler.
泄气阀，小龙头用来排空或降低压力的一种小阀门或小龙头，如锅炉上的