A method of eliminating pencil pipe defects in steel includes the step of flowing molten steel through a passageway (P) that may be formed by: an upper tundish nozzle (14) disposed beneath a tundish (12); nozzle plates (16) for controlling flow of the molten steel; and an entry nozzle (18) disposed between the nozzle plates and a mold. Nitrogen-containing gas is directed under predetermined gas flow conditions along substantially an entire length of the passageway. The gas may be directed to portions of the passageway formed by the upper tundish nozzle and the nozzle plates and into the passageway. The molten steel may be exposed to the gas directed under the predetermined gas flow conditions to a portion of the passageway formed by the entry nozzle. Instead of or in addition to exposure to the nitrogen-containing gas, the molten steel may be exposed to a reactive surface (94) formed of a CaO-ZrO2 composition, the reactive surface forming a portion of the entry nozzle. The nitrogen-containing gas may also be directed through a porous refractory sleeve of the entry nozzle and into the passageway. The gas flow conditions are effective to eliminate pencil pipe defects in the steel.
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