SMOKE EXHAUSTER IMPELLER Russian patent published in 2001 - IPC

FIELD: sintering. SUBSTANCE: impeller has central and side disks with main blades fitted between disks. Protective blades are welded to each inlet end face of main blades at angle of 20 - 30 deg to working surfaces by single-sided weld. Height of trapezium-shaped protective blades is equal to 0.4-0.6 of width of main blade inlet part and they adjoin central disk by their larger base. Rise of upper edge of protective blades over working surface of main blades is 0.015 - 0.02 at central disk and 0.007-0.01 of length of main blade at opposite end of protective blade. Working surface and end faces of protective blades are coated with very hard alloy layer whose thickness is equal to 0.1-0.2 of thickness of protective blade. EFFECT: possibility of repeated replacement of worn-out protective blades without impairing main blades, improved repairability and reliability of impeller, increased its service life. 3 cl, 3 dwg