CENTRIFUGAL PUMP Russian patent published in 2002 - IPC

FIELD: manufacture of pumps; centrifugal pumps for tube ball cleaning systems, for example tubes of turbine condensers. SUBSTANCE: proposed pump has impeller and spiral tap. Impeller is rated for parameters by power- speed coefficient of n_s=100 to 150; impeller is made in form of taper disk at center angle of 70 to 120 deg. with four spiral blades and zero angle of attack at rated mode, outlet angle of 12 to 24 deg. and chord-spacing ratio of blading of 1.3 to 1.7; relationship of said parameters is dictated by diffusivity of straight-way inter- blade passage not exceeding 4 to 10 deg. Blades have minimum height; distance between leading edge of blade at impeller inlet and adjacent blade by normal to it exceeding diameter of ball of cleaning system by amount of guaranteed clearance. Working surfaces of blades are inclined towards rotation of impeller. EFFECT: enhanced wear resistance of ball; reduced cavitation destruction in working passages of impeller; enhanced passability of balls at thick-and-fast loading. 6 cl, 4 dwg