GB1263799A - A dust separator system for a dust creating process - Google Patents

Abstract

1,263,799. Centrifugal separators. VACUBLAST Ltd. 21 Aug., 1970 [2 Sept., 1969], No. 43384/69. Heading B2P. In an apparatus in which granular material, e.g. blasting abrasive or coating powder, is applied in a stream of air to an article in an enclosure 1, Fig. 8, a centrifugal separator is provided for separating re-usable granular material from dust and/or debris and comprises a cylindrical hollow shell 17, Fig. 3, into which the stream of air containing the re-usable granular material, dust and/or debris is drawn through an annulus 18 within which are located inclined swirl-producing vanes 19, the re-usable material being removed through one or more longitudinal slots 22 in the wall of the shell and the air with dust and/or debris being discharged through a central outlet aperture 21. The aperture 21 communicates via an exit pipe 24, 20 with a dust separator 9. A conical hood 25 prevents the re-usable material passing through the perforated bottom 11 of the enclosure from falling directly into the separator shell 17. An orifice 29 to which a control valve is fitted may be provided in the bottom 28 of the shell 17 to permit a controlled quantity of air to enter the separator to increase its dust removal efficiency. The re-usable material collects at 3 in the bottom of a hopper 2 and is recirculated via a duct or hose 4 and an ejector nozzle on to the article in the enclosure 1. A screen 30 may be provided below the separator to remove any over-size debris from the re-usable material. In a modification, Fig. 5, the shell 17 is continued around beyond the slot 22 to form a divergent lip 26 providing a greater width at entry to, than at exit from, the slot. In a further modification, Figs. 6 and 7 (not shown) the slot is triangular in cross-section, its width increasing from the top to the bottom of the shell. In a further modification, Fig. 11, an aspirating nozzle 35, in the form of a slot similar in height to slot 22, separates entrained dust and debris from the re-usable material discharged through the slot 22. In modifications of Fig. 11, the nozzle points in the same direction as the slot 22, and is located immediately before, Fig. 13 (not shown), or after, Fig. 12 (not shown), the slot 22 so that the air flow into the nozle is in the reverse direction to the material leaving the slot. An alternative arrangement with the separator mounted horizontally and a different system of collecting the separated re-useable material is described, Figs. 9 and 10 (not shown).