Abstract: Apparatus for inspecting the chimbs of cylindrical articles such as kegs or drums comprises means for rotating a keg about its cylindrical axis and sensing means arranged to engage the chimb of the keg and to sense displacement of the chimb from a predetermined position. In the preferred embodiment, a lower sensing unit 18 has two actuating arms 132 and 232 pivoted about horizontal axes. Each arm has at one end a roller (136,236) which engages the chimb 302 of a keg 300 under the resilient bias of a spring (154,254). At the other end the arm has a steel plate (138,238) moving over a proximity sensor (152,252). Deformation of chimb 302 at any point in its circumference causes the plate on one or other arm to move away from the proximity sensor which gives an appropriate signal to electrical control circuitry of the apparatus. An upper sensing unit 20 is provided so that the upper and lower chimbs of a keg can be inspected simultaneously.