Abstract: A fluid flow machine, particularly a centrifugal pump, wherein the casing has a tubular first portion serving to convey a stream of fluid radially toward a pump shaft which drives one or more impellers. The casing has a second portion with an arcuate band-like wall which spacedly surrounds the shaft and defines a passage having an oval cross-sectional outline and receiving fluid from the outlet of the first portion. A cylindrical outlet of the passage is adjacent the foremost impeller or the only impeller of the pump. One or more guides are provided in the passage to control the flow of fluid from the outlet of the first portion of the casing toward and into the range of the foremost impeller.

Abstract: Two components of the housing of a centrifugal pump have adjoining surfaces and define an opening for an annular insert which surrounds a rotary shaft. The insert is surrounded by a sealing ring which is biased into sealing engagement with the peripheral surface of the insert and against the adjacent internal stops of the two components by a two-piece ring under the action of screws which mate with the insert and are caused to urge the two-piece ring against the sealing ring. The adjoining surfaces of the two components are grooved at the opposite sides of the insert and receive rope-like sealing members which are in sealing contact with the adjoining surfaces of the two components under the action of bolts which urge the two components toward each other. The sealing ring has recesses which sealingly receive the adjacent end portions of the sealing members.