| 摘要 |
The present invention relates to a ventilation duct for passage through a fire compartment-limit, for instance a wall, a floor, a ceiling or another structural part in a fire compartment-divided building, wherein the invention is characterized in that the ventilation duct is a prefabricated unit which comprises an inner tubular member (1) and an outer tubular member (2) with a fireproof insulation (3) enclosed between the tubular members (1, 2) which parts together correspond to a chassis of fire resistance class A or B. A damper valve (6) of fire resistance class F is preferably pivotally mounted in the inner tubular member (1). In this respect the invention is characterized in that the damper valve (6) is pivotally mounted at the midway point of the inner tubular member (1) and is adjusted by a setting device (8-11) mounted on the ventilation duct. |
