(57) A water jet nozzle assembly comprises a hollow cylindrical header being supplied with cooling water under pressure and formed in its both sides with a series of apertures, and two elongated curved plates having a substantially quadrantal cross-section secured to the header with one longitudinal sides of the plates adjacent to lower edges of the apertures formed in the header and with the other longitudinal sides of the plates upward extending.
In the other aspect of the invention, a water jet nozzle assembly comprises a U-shaped trough-like header, an elongated curved plate having a substantially semicircular cross-section formed in its bottom with a plurality of apertures with substantially equal intervals and arranged on the trough-like header so as to close an upper open side of the trough, with longitudinal sides of the curved plate upward extending, and converter plates arranged above and spaced apart from the respective apertures formed in the curved plate to turn water flows jetted from the respective apertures into substantially horizontal directions.
The water jet nozzle assembly according to the invention is able to effectively cool undersides of materials such as steel plates or strips.