在故宫中，大殿前、庭院中都有摆放大铜缸，这些铜雕大缸是雕塑工艺中的一种铸铜雕塑，腹宽口收，容量极大，而且装饰精美，两耳处加饰有兽面铜环，据说，这些大铜缸雕塑最初是用来防火的，
因故宫中的主要建筑材质以木质为主，很易引起火灾，而在通常在门口的铜雕大缸中注满水，以备不时之需。

In the Palace Museum, large copper cylinders are placed in front of the hall and in the courtyard. These copper cylinders are a kind of cast copper sculpture in the sculpture process. They have wide abdomen, large capacity and beautiful decoration. They are decorated with beast-faced copper rings on both ears. It is said that these large copper cylinder sculptures were originally used for fire protection.

Because the main building material in the Palace Museum is mainly wood, it is easy to cause fire, but usually in the doorway of the copper cylinder filled with water, in case of occasional need.