Abstract: The flow path of liquld steel in the beam blank mould was analzed using mathematical and hydrodynamic model. It was found that the flow path of hot meta in bearn blank mould, the scale of vertx area at moud web and the fluctuation of melt surface were influenced by included angle of nozzle, tilt angle of nozzle spout, casting speed and immersion depth of nozzle. The optimum technical parameters of nozzle that leads to optimum flow path in beam blank mould at normal casting speed were that included angle is 120°,spout tilt angle is 9° and immersion depth is 75 mm (150 mm in prototype).