| 摘要 |
Provided is a sleeve for glass tube molding, the sleeve being capable of: preventing the weakening of clamping force between a metal tip and a metal holding fixture even if the distance between the metal tip and the metal holding fixture increases due to the thermal expansion of a sleeve shaft; and ensuring the coaxiality, on the sleeve shaft, of the metal tip, the metal holding fixture and a refractory tube. This sleeve 1 for glass tube molding comprises: a sleeve shaft 10; a refractory tube 30 into which the sleeve shaft 10 is inserted in a coaxial manner; a metal tip 20 which is at one end of the refractory tube 30, and is fixed to the tip of the sleeve shaft 10; and a metal holding fixture 40 which, at the other end of the refractory tube 30, is slidably inserted in the sleeve shaft 10, and clamps and holds the sleeve shaft 10 together with the metal tip 20. A part of the inner circumferential surface of a through-hole 40A1,which is in the metal holding fixture 40 and through which the sleeve shaft 10 is inserted, is in close contact with the outer circumferential surface of the sleeve shaft 10. |
