Patent ID: 11014844

Abstract:
This sleeve for glass tube molding is provided with: a sleeve shaft; a refractory tube into which the sleeve shaft is inserted in a coaxial manner; and a metal tip that is fixed to the tip of the sleeve shaft, and regulates movement of the refractory tube in the axial direction and towards the tip. The sleeve for glass tube molding is capable of ensuring the coaxiality of the metal tip and the refractory tube on the sleeve shaft. The metal tip comprises: an annular collar member that has a tapered outer circumferential surface of which the cross-sectional area gradually increases towards the tip of the sleeve shaft, and that is coaxially fitted to the tip of the sleeve shaft; and a main body member that has a tapered outer circumferential through-hole of which the cross-sectional area gradually increases towards the tip so as to conform to the outer circumferential surface of the collar member, and that is fitted to the collar member via the through-hole.