Fibre drawing or extruding details

CCHEMISTRY METALLURGY C03Glass mineral C03BMANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES

C03B2205/00Fibre drawing or extruding details

C03B2205/02Upward drawing C03B2205/04Non-vertical drawing C03B2205/06Rotating the fibre fibre about its longitudinal axis C03B2205/07Rotating the preform about its longitudinal axis C03B2205/08Sub-atmospheric pressure applied C03B2205/09to the outside of the preform or fibre C03B2205/10pressurised C03B2205/12Drawing solid optical fibre directly from a hollow preform C03B2205/13from a hollow glass tube containing glass-forming material in particulate form C03B2205/14comprising collapse of an outer tube onto an inner central solid preform rod C03B2205/16the drawn fibre consisting of circularly symmetric core and clad C03B2205/20Irradiation of the base fibre during drawing to modify waveguide properties C03B2205/30Means for continuous drawing from a preform C03B2205/32Simultaneous drawing of multiple preforms to separate mulitiple fibres C03B2205/40Monitoring or regulating the draw tension or draw rate C03B2205/42Drawing at high speed C03B2205/44Monotoring or regulating the preform feed rate C03B2205/45Monotoring or regulating the preform neck-down region with respect to position or shape C03B2205/46Monotoring or regulating the preform position with respect to the draw axis C03B2205/47Shaping the preform draw bulb before or during drawing C03B2205/50Cooling the drawn fibre using liquid coolant prior to coating C03B2205/51using liquified or cryogenic gas C03B2205/52by direct contact with liquid coolant C03B2205/53by passage through liquid coolant bath C03B2205/54After-treatment to remove coolant attached to cooled fibre C03B2205/55Cooling or annealing the drawn fibre prior to coating using a series of coolers or heaters C03B2205/56Annealing or re-heating the drawn fibre prior to coating C03B2205/57Recovering, recycling or purifying the coolant C03B2205/60Optical fibre draw furnaces C03B2205/61Recovering, recycling or purifying the inert gas C03B2205/62Heating means for drawing C03B2205/63Ohmic resistance heaters C03B2205/64Induction furnaces, i.e. HF/RF coil C03B2205/66Microwave or similar electromagnetic wave heating C03B2205/67Laser heating C03B2205/68Hot gas C03B2205/69Auxiliary thermal treatment immediately prior to drawing C03B2205/70Draw furnace insulation C03B2205/72Controlling or measuring the draw furnace temperature C03B2205/74Means for moving at least a part of the draw furnace C03B2205/80Means for sealing the preform entry or upper end of the furnace C03B2205/81using gas C03B2205/82Means for sealing the fibre exit or lower end of the furnace C03B2205/83using gas C03B2205/90Manipulating the gas flow through the furnace other than by use of upper or lower seals C03B2205/91by controlling the furnace gas flow rate into or out of the furnace C03B2205/92using means for gradually reducing the cross-section towards the outlet or around the preform draw end C03B2205/96using tangential feed approximately perpendicular to the draw axis C03B2205/98using annular gas inlet distributors