The present invention provides an optical fiber preform-heating furnace that is simple in its structure and excellent in uniformity of the temperature distribution in a circumferential direction of an optical fiber preform. The optical fiber preform-heating furnace includes a furnace core tube into which an optical fiber preform is supplied; a heater that surrounds the furnace core tube; a pair of electrode connection portions with which the heater is provided and has a face opposing to an outer...

In a wire insulating line, a cooling device that cools down a traveling high-temperature linear material, which is resin-coated by an extruder, in cooling water includes a reservoir tank that reserves the cooling water and allows the linear material to pass therein, and water spray nozzles that are provided in plural numbers in the reservoir tank with a gap along the linear material traveling direction and spray water to the linear material in the cooling water. Further, in the wire insulating l...

An underwater cutting pelletizer is disclosed wherein a water chamber is circular in plan, an inlet portion is formed on one side in a diametrical direction of the water chamber to introduce cooling water into the water chamber, and an outlet portion is formed on the other side in the diametrical direction of the water chamber to discharge the cooling water from the interior of the water chamber to the exterior, the inlet portion being in a divergent shape in an inflow direction of cooling water...