| 摘要 |
A supplying tube for a molten glass, which is placed in a downstream end portion of a supplying passage directing the molten glass flowing out of a melting furnace to a forming vessel in a forming furnace, has a small diameter tube portion which has a small flow passage area and is provided at an upstream side, and a large diameter tube portion which is provided at a downstream side of the small diameter tube portion and has a large flow passage area. An expanded diameter tube portion of which flow passage area gradually expands toward the downstream side is interposed between the small diameter tube portion and the large diameter tube portion. The small diameter tube portion, the expanded diameter tube portion, and the large diameter tube portion may be integrally and continuously connected to one another. |
