| 摘要 |
<p>The decorative armoured door is made of cast bronze, the casting process entailing the pouring of molten bronze into sand moulds. Prior to casting, steel tubes are placed in the mould, aligning in the central major door plane, and functioning as ducts for lock actuated slidable steel bars. Some of the embedded tubes may be sealed to constitute a defensive sprinkler system, and include controls for the emission of e.g. a tear gas spray through the external door face. Hinge fitting may be offset internally, being cast in one piece with the door, and being mounted on reciprocal fittings incorporated on a vertical beam which is built in at the head and foot.</p> |
