Damair centrifugal blowers are offeredas per standard amca 210. Following are some constructional features of this blowers which include: casing is robustly constructed using suitable sections of mild steel/stainless steel; housings are free from all defects; sheets used were cut on nibbling machine to avoid deformation. Welding of casing was done with fixtures and dc welding sets to avoid distortion; for maximum efficiency, this casing is designed. Impeller/rotor of the blower is designed for the required combination of air quantity and static pressure; following are some of the technical features of this blower which include: is machined after careful fabrication; hub of cast iron is machined within close tolerance; impeller is made in one piece and securely keyed in the shaft; rotor along with other unmachined rotating parts is statically and dynamically balanced so as not to cause any vibration. Shaft is machined out of en-8 forging or suitable material and has close tolerance at the rotor, coupling, pulley and bearing diameters. Some of the constructional features of these centrifugal blower which include:size of the shaft is calculated on the basis of proper stress which does not exceed 30 per cent of its static limit in tension or 18 per cent of tensile strength; shaft is designed for at least 20 per cent higher speed than the normal operating speed; bearings used are normally ball or roller type suitable to take up the necessary radial load as well as the axial thrust.
