Abstract: A sample from a bath of killed molten steel which contains aluminum is removed with a vessel having a cover which undergoes at least partial disintegration on contact with molten metal and allows molten metal to fill the vessel as soon as the latter is lowered to a preselected level. The internal space of the vessel contains a strip of magnesium and a strip of zirconium. Magnesium evaporates with an explosion as soon as it is contacted by molten metal and thereby enters into a chemical reaction with oxygen in the vessel while also expelling the remaining air through the partially disintegrated cover to further reduce the likelihood of reaction between aluminum and air which is entrained with the immersed vessel. Zirconium dissolves in the metal which fills the vessel and bonds oxygen close to the surface surrounding the internal space of the vessel.

Abstract: A blast heating apparatus includes an inner metal shell having therein a refractory lining. An outer metal shell surrounds at least a portion of the inner metal shell and defines therewith a double shell structure. Spacers are positioned between the outer and inner metal shells to define therebetween a gap. At least a portion of such gap is filled with a pourable dry material having a grain size of up to 8 mm and a heat conductivity of at least approximately 1.5 W/Km.