GB1053222A - - Google Patents

Abstract

1,053,222. Centrifugal separators. AMETEK Inc. Aug. 9, 1963, No. 31575/63. Heading B2P. A centrifuge for separating solids from slurries having relatively low solids content comprises a drum 10 rotating about a horizontal axis and a separator-conveyer assembly 42 mounted within the drum 10 for rotation at a different speed about the same horizontal axis and forming with the drum a solids chamber and a liquid pond in coaxial relation to each other, the slurry being continuously fed by means of a pipe 59 along the axis of the drum at one end thereof and the separated liquid being removed by means of a skimmer tube extending into a liquid collecting chamber 24 at the other end of the drum and adapted to maintain a constant depth of liquid in the chamber. The slurry is accelerated to the speed of rotation of the liquid pond prior to reaching the latter by means of a conicalthroated member 50 in corporating vanes 56. The drum 10 is driven directly by means of a pulley 15, and the assembly 42, comprising a tubular element 43 to which are fixed longitudinally-spirally extending vanes 47 surrounded by a spiral strip 52, is driven at a a lower speed than the drum from an end shaft 25 thereof through a two-stage epicyclic gear reducing unit 35 and a splined connection 41. The spiral strip 52 extends around the conical member 50 and serves to remove accumulated solids from the inner surfaces of the drum and of a truncated conical hollow insert 16 and convey them to a chamber 17 and thence through ports 18 to a chamber 19 within a housing 20 surrounding the drum 10. The liquid component of the slurry discharges through ports 22 into the chamber 24 from which it is removed by the skimmer tube 70 which is connected to an axially displaceable non-rotatable threaded shaft actuated by a handwheel to adjust the position of the nozzle 71 of the tube 10 for maintaining the liquid pond at the desired radial dimmension. The conical member 50 is secured to the vanes 47 and is supported in a bearing. The vanes 56 are mounted on a rod 54 and are resiliently urged into frictional contact with the inner surface of the member 50 by means of a spring 57. The sun gear 61 of the gear unit 35 is normally held stationary by an overload linkage comprising an arm 63 fixed to the sun gear shaft 62 and abutting a spring-loaded bell crank 64, 65, Fig. 2. Should the centrifuge become overloaded, the arm 63 trips the bell crank to its dotted position thereby permitting rotation of the sun gear 61, and interruping the rotation of the separate conveyer 42 until the overload is reduced.