摘要 |
<p>A connector for connecting lengths of metal tubing such as used for air-conditioning or central heating ducts, comprises a cylindrical end part for insertion into an open end of the tubing. In order to provide a seal between the connector and the tubing the connector has a recess containing a hollow, flexible sealing ring into which fluid can be injected to expand the ring. In order to ensure an adequate seal both before and after expansion of the sealing ring the latter has outwardly projecting sealing flanges which, before expansion of the sealing ring, make a seal due to their own inherent resilience and/or the resilience of the sealing ring, and, after expansion of the sealing ring, form a seal under compression. In one embodiment of the connector a sealing flange is adapted to fold over and lie between the respective faces of the connector and the tubing to prevent metal to metal contact between them.</p> |