Centrifugal casting of tubes, lenses, etc., from molten glass - where molten tin inside high speed rotor forms mould wall on which glass solidifies

摘要

A rotor driven by a motor is fed with a liq. (30), esp. molten tin, which has a higher density than the melt being cast, which is esp. glass. The speed of the rotor causes the molten tin to form a cylindrical mould wall onto which a glass tube (40) can be cast and may be removed continuously or discontinuously. The molten tin (30) is pref. circulated through the rotor, and its thickness is pref. used to determine the dia. of the mould in which tube (40) is cast. Pref. the rotor (22) rotates on a horizontal axis for mfg. glass tubes; but other pref. plants use a rotor with a vertical axis, for the centrifugal casting of lens-shaped or parabolic blanks. Used e.g. for continuous casting of glass tubes; or for the mfr. of parabolic mirrors with a good surface for astronomy.