| 摘要 |
<p>The exhaust valve has a valve (A) with a casing (3), a fluid inlet port (1) and outlet port (2), and a valve disk vertically movably mounted in the casing. A valve seat (7) is mounted in the casing between the inlet and the outlet ports, while an actuator in the casing moves the disk vertically away and into contact with the seat to establish and block the passage of chemical vapour from the inlet to the outlet port. - A bellows sealingly houses the disk and vertically expands for expansion and contraction in synchronism with the disks vertical movement. A sheathed heater (14) in the casing inside the bellows has an upper portion fixed to the upper end of the casing, and its lower end fixed to the valve disk. The heater is made of a coiled hollow tube and vertically expands in sync with the bellows expansion and contraction. The heater has a heating wire inserted into its hollow inside for heating the bellows and the valve disk.</p> |
