... pipe is used for blowing in steelmaking, it is made of steel pipe with inside & outside surface calorized & ceramic coated ... , anti-erosion; TypesCeramic coated pipeCalorized pipeCalorized & ceramic coated pipeThickness of calorizing layerWithoutOD 0.15~0.25mmID 0,15~0,25mmOD ... ~0,20mmWithoutOD 0,25-0,60mmID 0,10~0,20mmNumber of layers3 layersSteel pipe + ceramic coating inside and outside3 layersSteel ...