The invention relates to an injection device for the reliable introduction of a fluid into a metallurgical vessel having a refractory lining, the device being removably insertable in the lining; comprising a refractory first body (2) and a refractory second body (3) fittingly assembled, the first body (2) being made of a refractory material less permeable to the fluid than the material of the second body (3), the first and second bodies having each a surface (4, 5) adapted to contact molten metal; and having each fluid passages (6, 7) extending from fluid feeding means (8) to a surface (4, 5) adapted to contact molten metal, the relative flow resistance of the fluid passages (7) in the second body (4) being higher than that of the fluid passages (6) in the first body (2), the fluid passages (6) in the first body (2) being constituted of slots or bores. According to the invention, the fluid passages (6) in the first body (2) are independent from the fluid passages (7) in the second body (3). Such an injection device permits the reliable introduction of a fluid into a metallurgical vessel even when the injection device has already been used.
