| 摘要 |
<p>A fire isolation device having a valve designed to close after a given temperature has been reached by a fusible nose member in the form of a sleeve of fusible material. The device has a passageway therethrough and a self-closing valve member having a poppet and a seat disposed in the passageway with the poppet being biased toward the seat to a valve closed position. At least one aperture through the nose member provides for continuous fluid flow through the device around the poppet and the seat. The nose member is positioned to hold the valve in an open position against the bias on the poppet. The seat has a flow path on its outer end dimensioned to fit the nose member and a flow path towards its inner end larger in diameter than the nose member in an area occupied by the aperture to permit flow therethrough when the nose member holds the valve in an open position. The nose member is made of a material designed to melt in the neighborhood of 700 DEG F. when the fire isolation device is exposed to 2000 DEG F. for 15 minutes, for example, after which it will collapse into the larger diameter permitting the bias to close the valve. The nosse member is designed to melt prior to an attached component in order to prevent fluid leakage at the component. The remainder of the parts of the device are made of a higher temperature resistant material. In a second embodiment a bi-directional device is provided in which valve and nose members are positioned in both ends thereof.</p> |
