OPTICAL FIBRE WORKPIECE, METHOD OF MAKING OPTICAL FIBRE WORKPIECE AND GLASS BAR FOR MAKING OPTICAL FIBRE WORKPIECE Russian patent published in 2010 - IPC C03B37/12 

FIELD: chemistry.

SUBSTANCE: method of making an optical fibre workpiece through thermal treatment of a glass workpiece having a glass bar and a porous body made from quartz glass deposited on the lateral surface of the glass bar and having a part suitable for use when producing optical fibre and parts not suitable for use which are adjacent to the part suitable for use, where thermal treatment is carried out using a heater in a heating furnace for glass transition of the porous body made from quartz glass involves the following steps: heating the glass workpiece while moving it in its axial direction relative the heater; stopping relative movement or reducing speed of relative movement when the part unsuitable for use, lying at the tail end opposite the direction of movement of the glass workpiece, reaches vicinity of the heater; heating the part unsuitable for use during a preset time while maintaining the heating temperature at which the porous body made from quartz glass undergoes glass transition; lowering the heating temperature in the heating furnace to temperature defined by adding 200°C to the annealing point of the quartz glass; taking the glass workpiece out of the heating furnace without raising heating temperature to glass transition temperature of the porous body made from quartz glass.

EFFECT: efficient method of obtaining optical fibre workpiece.

9 cl, 13 ex, 9 dwg