A steel converter having bottom tuyeres supplied from a plurality of solids-weighing tanks which discharge selectively under pressure into a single conduit serving the tuyers. The weighing tanks are isolated from the conduit by individual flex-joints which permit relative motion between their ends, without detrimental stresses as a result of pressure-changes, while maintaining aeration of the material passing through the flex-joint.

An equipment for the continuous, pneumatic introduction of finely divided materials, in particular coal dust, into several consumption sites, in particular into the tuyeres of blast-furnaces is characterized by combining systems partly known in such manner, that a plurality of double-story vessels is preceded by a distribution system comprising a supply bin with metering conveyor scale and distribution bin. A pressure-resistant bucket-wheel distributor is mounted underneath every pressure-vessel...

In connection with the bottom blown oxygen method of making steel, gases and powdered materials such as fluxes and additives are injected into the hot metal of the converter through tuyeres in the bottom of the vessel. The powdered materials are stored in pressure vessels and selectively transported to the converter by entraining the materials in high pressure process gases such as oxygen. Means are provided for maintaining constant material flow rates independent of gas pressure and flow variat...