Knowledge pictogram

Knowledge

A new installation method for fibre optic cables in conduits

A new technique for the installation of conventional fibre optic cables in commonly used conduits using the viscous flow of air is decribed. Blowing experiments have been carried out, using different cables, conduits and lubricants. For better understanding also pulling experiments with conduits having different tortuosities and supporting laboratory experiments have been performed. The non linear pressure decay in the tube in which the cable is blown is experimentally verified. Furthermore a simple experiment for measuring the cable stiffness is described. With one installation unit 1 km fibre optic cable can be installed with speeds up to 1 m/s. Even 36 right angled curves in the conduit can be passed. In less than one hour a reel with 2100 m fibre optic cable can be installed using the installation units in cascade, without synchronisation problems. This means that longer cables can be installed in the future. The described method is very simple because for instance no pulling ropes have to be installed. Furthermore the cable strain can be kept low. Halfway 1988 1000 km fibre optic cable have been installed in the public network of the Netherlands using the described method, considerably saving man and time.

Proc. 37th IWCS (1988) 172
W. Griffioen