A centrifugal pump (1) includes a pump casing and a shaft (11) which is rotatably mounted therein and on which an impeller (10), for delivering fluid, is arranged rotationally fixed. A cartridge shaft seal (13) is arranged between the shaft (11) and an opening (16) of the casing, through which opening the shaft (11) is led. The cartridge shaft seal (13) includes a sleeve (22) which surrounds the shaft (11) at least in the region of the opening 16 and which is connected to the shaft (11) releasably and rotationally fixed, by way of a clamping device (29) which is arranged on the outer side of the sleeve (22). The clamping device (29) includes clamping jaws (32) which only engage on the outer side of the sleeve (22) and non-positively connect the sleeve (22) to the shaft (11).