| 摘要 |
The prefabricated ducts (11) have rectangular end cutaways (16) in the side walls (14, 15), giving access to cable or bar conductor interconnections within. A channel (12a) along the centre of te top-plate (12) has cross-channels (12b) located above the cutaway edges. The junction (JJ') of abutting sections is covered by clip-o half-shells (21, 22) having a locating tabs engaged in holes (17) in each side wall, and secured by through bolts (6) in each corner (22c). A narrow flange (23) retains the shells on the lower duct edges, while wider top flanges (24) overlap each other, and the duct top. Sealing strips are provided for each vertical cut-away edge (30) and between the top flanges, under each end of which is inserted a moulded moisture trap (4), seated in the cross-channels (12b).
|
