Abstract: A blade is disclosed for use in a mixing impeller assembly. The blade includes a top skin element and a bottom skin element without an internal framework in between the elements. A unitary pre-shaped tip element is attached at an end of the blade to the top and bottom skin elements. The tip is welded to the top skin and the bottom skin, and has a bevel at the weld location. The top skin has an edge that abuts the tip and the lower skin has an edge that abuts the tip, and respective bevels are provided on these edges.

Abstract: In order to extend the life of mixing impellers which circulate materials, and particularly which suspend solids, in the form of particles which erode the blades of the impellers and place a practical limit on impeller speed and/or angle of attack due to increased erosion at high flow velocity (erosion being a function of the cube of the velocity), the blades are constructed from blades into an airfoil configuration which does not limit the thickness of the plates and thereby allows the use of thick plates having extended life. An erosion resistant layer is located at least over the leading edge region of the blade and the shape of the blade reduces velocity of flow over the leading edge; the camber of the blade being maximized midway between the leading and trailing edge. The suction surface of the blade in the region subject to erosion is continuous thereby avoiding discontinuities which form vortices which enhance erosion.