| 摘要 |
A fire clamper blade (5) of a circular shape and having a seal (6) adapted about its perimeter for sealing the damper blade under normal operating conditions and the blade further having adapted about its perimeter an outer rim seal of intumescent seal material (7) for establishing a leakproof seal under a fire condition. The invention is implemented by way of having the intumescent seal material (7) protected by a refractory seal material (8) placed over the intumescent seal material (7) so as to substantially cover the entire perimeter of the damper blade (5). |
