GB747359A - Centrifugal pump or compressor - Google Patents

Abstract

747,359. Centrifugal pumps and compressors. WORTHINGTON CORPORATION Nov. 16, 1953, No. 31734/53. Class 110(1) A multi-stage centrifugal pump or compressor comprises an inner casing connected to a hollow cylindrical outer casing both casings being provided with communicating inlets and outlets, and the inner casing has continuous circumferential en largements which cooperate with circumferen tial sealing surfaces dis posed on the inner surface of the outer casing and on opposite sides of the outlet therein to form at least one seal and at least one sliding joint between the casings, the seal and sliding joint being of substantially equal diameters. The centrifugal pump shown in Figs. 1A and 1B comprises an inner casing 2 which is split on a horizontal plane and is inserted in a cylindrical outer casing 1 which is without any longitudinal joint. The outer casing 1 has an inlet 7 and an outlet 16 which communicate respectively with the eye 5 of the first stage impeller and with the outlet 15 of the inner casing 2. Cylindrical enlargements 19 and 20 on the inner casing 2 engage corresponding bores 21 and 22 in the outer casing 1. Labyrinth grooves 26 or other sealing means are provided.. Preferably, the diameter of bore 22 is, as shown, slightly greater than that of bore 21 to facilitate assembly. The inner casing 2 is flanged at one end for attachment by studs 24 to the outer casing 1, but at the other end is free to slide longitudinally to accommodate thermal expansion. To reduce the unbalanced longitudinal thrust taken by the studs 24, the annular space 18 enclosed between the enlargements 19, 20 is subjected to the discharge pressure through a gap 17 and a chamber 27 is subjected to the suction pressure at the inlet 7 through pipes 28. Figs. 8 and 1B combined show a modification in which the stuffing box 8<SP>1</SP> and the adjacent bearings (not shown) are carried by the inner casing 2<SP>1</SP>. The bearings are supported by a bracket 10<SP>1</SP>. Two cylindrical enlargements 11<SP>1</SP>, 12<SP>1</SP> are provied on either side of an inlet 4<SP>1</SP>. In a further embodiment, the first stage has a double-inlet, impeller.