Manufacture of optical cables

摘要

In order to feed water blocking or hydrogen absorbing powder into an integral optical cable of the type where one or more optical fibres (2) are loosely enclosed within at least one of a plurality of longitudinally extending closed channels (3) formed in an extrudate, the powder is fed into the narrow delivery tubes (10) which feed the fibres through the extruder and into the channels. The powder (13) is fed through the delivery tubes by an impelling means which may be either a vibrator (15), or a rotating hollow screw means which surrounds the fibre (2) within the tube (10).