Preforms are the layered cylinders of glass, made on lathes using chemical deposition vapor flows, burners for heating and melting glass and pressure control to retain the shape while it is being formed. Once complete, the preforms are stood upright in drawing towers and the lower end is drawn as a fibre, which is coated and taken up on a drum winder. Preforms incorporate both the core light transmission layers and the cladding, different layers of refractive density that keep the beam of light traveling down the fibre, instead of leaking out the sidewalls, even if the fibre bends and loops.
Manufacturers use MFCs to:
Fibre drawing is the means of heating the end of a glass preform and shaping the melting end into a cone that creates a continuous stream of molten glass. This then descends and cools into a fibre which must then be guided in a way that will not break or alter it, while checking the thickness and adding layers to protect it.
In fibre draw processes, manufacturers use flow and pressure control to:
Combining fibres into packaged strips of fibres for easy installation in groups, like ribbon cables of electrical wires.