| 摘要 |
<p>Polyurethane is formed in a mould on a tiltable carrier. The mould is lined at least on two faces to give a moulding of a door. A welded steel reinforcement frame is fixed on pins extending to edges of the moulding so that the frame becomes encapsulated in the moulding. The frame may suspend a sheet of fire resistant or anti-ballistic material. After an interval, the mould is tilted to an upright position. After moulding, the door is removed from the mould, stripped of flash and release agent, and finished like wood. The door may be of security and/or external quality, and included as part of a door set.</p> |
