| 摘要 |
<p>A method and apparatus for installing optical fibres (11) in tubes or ducts (29). An optical fibre is fed from a reel (13) into a small diameter feed portion of duct (25), and compressed air is introduced into the duct. This advances the fibre, using viscous drag forces, into a main duct of larger diameter. There is a pressure drop at the intersection of the two ducts. Subsequently, the advancement of the fibre is continued by maintaining the air supply, and the viscous drag forces, acting on the increasing length of the fibre in the duct, advance it along the duct. Two or more fibres, which may be unsheathed primary coated fibres, may be installed simultaneously.</p> |
