Sleeve for glass tube molding

摘要

Provided is a sleeve for glass tube molding that, without reducing the mechanical strength of the sleeve shaft, can prevent foreign objects such as rust from generating off the sleeve shaft and can prevent foreign objects such as rust from adhering to molten glass. The sleeve for glass tube molding is equipped with a sleeve shaft having a through-hole, and is equipped with a pipe member comprising a material having superior rust resistance to the sleeve shaft. The pipe member is provided with a main body portion, and a tapered portion. The through-hole is provided with an insertion portion into which the main body portion is inserted, and a contact portion with a tapered shape whereat the outer peripheral surface of the tapered portion comes into contact with one end of the through-hole. A portion or all of the inner surface of the through-hole is covered by inserting the pipe member into the through-hole.