Abstract: A pour throat nozzle for a plasma arc centrifugal treatment system includes a substantially cylindrical throat section, with a generally arch-shaped, downwardly-facing surface at smaller radius extending above the plane of the bottom of the throat section, and with this connecting to a generally cylindrical section extending below the aforesaid plane at an inside radius much larger than the radius of the throat section. Furthermore, a method of reforming an orifice of a pour throat in a PACT system centrifuge includes adding ceramic material to the melt, heating and mixing the ceramic material with the melt, then slowing rotation of the centrifuge so that the mix pours into the inlet orifice of the nozzle.