| 摘要 |
Air ducts of rectangular cross-section are joined end to end by flanges formed from angle sections (5). The outer edge of a parallel (7a) and transverse flange (7b) is turned over to form a rounded edge (11), and a reentrant groove (13) is formed at the junction of the two flanges. The parallel flange fits inside the duct wall (1), whilst the other one forms the joint flange. The flange is secured to the duct by a clamping strip (49) which is clipped between the duct wall and the rounded edge of the transverse flange. |
