摘要 |
The invention provides an improved means of opening the outlet of a molten metal handling vessel. It comprises a valve (6) having relatively moveable valve parts (7, 9 and 8, 11) and a frangible tube (13) through which gas can be passed, the tube (13) extending through the valve parts (7, 9 and 8, 11) into the outlet (5a) of the vessel, whereby opening of the valve (6) by relative movements of the valve parts (9, 11) breaks the tube (13) so that it does not obstruct opening, the end of the frangible tube (13) through which the gas exits being provided with means (13b, 27) to allow the gas through but to prevent ingress of particulate material into the tube (13). |