Patent ID: 8695379
Filing Date: 2014-04-15
Classification: C03B

Abstract:
1. A method of applying traction to an unclad elongate cylindrical element produced by the fusion of a core preform of glass material to improve straightness and concentricity of the core preform, said cylindrical element being usable in a process of producing an optical fibre, comprising: a) providing, prior to application of a cladding, traction of the unclad elongate cylindrical element along an axis of advance, said providing traction comprising contacting at least a first and a second traction pulley to said unclad elongate cylindrical element and causing said first and second traction pulleys to rotate about respective axes, said traction pulleys being in a common plane and movable between a rest position in which the first and second pulleys are positioned away from each other and not in contact with the elongate element and an activation position in which the first and second pulleys approach each other and are in contact with the elongate element; and b) imparting, prior to application of a cladding, a twist to the unclad elongate cylindrical element about said axis of advance.