When returning empty cylinders, close the valve before shipment. Leave some positive pressure in the cylinder.

返还空瓶时，在运输之前关闭阀门，使钢瓶内部保持正压 。

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When returning empty cylinders, close the valve before shipment. Leave some positive pressure in the cylinder.

返还空瓶时，在运输之前关闭阀门，使钢瓶内部保持正压 。

youdao