GB1129516A - Improvements in or relating to magnetic filters - Google Patents

Abstract

1,129,516. Magnetic separators. M.E.L. EQUIPMENT CO. Ltd. 11 Aug., 1966 [26 Oct., 1965], No. 45267/65. Heading B2J. A magnetic filter for removing ferromagnetic particles from a fluid comprises an inner core 1 consisting of a series of co-axial discs 2 of soft ferromagnetic material spaced apart by cylindrical permanent magnets 3 having like poles opposing each other so that adjacent discs 2 form pole pieces of opposite polarity, and an outer cage 12 fitted round the core 1 and consisting of a series of spaced, co-axial annular members 13, Fig. 1, or 26, 27, Fig. 2, of soft ferromagnetic material which are each located adjacent a respective one of the discs 2 to form an extension of the pole piece formed by that disc so that when fluid containing ferromagnetic particles flows past the members 13 or 26, 27 such particles are attracted to these members, the core 1 and the cage 12 being capable of being separated from one another by axial movement of one relative to the other. The discs and the magnets 3 are supported on a tube 4 and held between plates 5, 6 which are clamped between nuts 7 and a collar 8 secured on a hollow tie bolt 9. Rods 10, 11 securing the collar 8 to the bolt 9 form a handle. As shown in Fig. 1, the annular members 13 are in the form of plates substantially co-planar with the discs 2 and are mounted on a sleeve 14 of non-magnetic material between its flanged upper end 15 and its turned lower end 16, the plates being held in assembled relationship by four tie bolts, of which one is shown at 17, with sleeve-shaped spacing elements 18 surrounding the bolts between the plates. Each pair of bolts is connected to a U-shaped handle 19. The sleeve 14 has a sliding fit on the discs 2. The core 1 and the cage 12 are housed with a sliding fit in casing 24. The plates 13 may be formed at their edges with recesses (25), Fig. 2 (not shown), so that the length of the outer periphery of each pole piece extension is increased thereby increasing the separation of ferromagnetic particles from the fluid as the latter passes the edges of the plates 13. The recesses in one plate are preferably staggered relative to those in adjacent plates. To clean the filter the cage 12 and the core 1 are drawn apart axially by means of the handles 10, 11 and 19 whereby the plates 13 of the cage will no longer be magnetised and the ferromagnetic particles collected on the edges of these plates will fall off or can be readily removed as by flushing. In Fig. 3, the extensions of the pole pieces are each formed by a pair of rings 26, 27 made from corrugated strips which produce fin-like radial projections, Fig..4 (not shown), on the outer side of the sleeve 4. The rings 26, 27 of each pair of corrugated rings have the same polarity, being separated by a spacing ring 28 of soft-ferromagnetic material substantially coplanar with the associated disc 2 of the core 1. The fin-like projections may be in line or staggered.