Rotating machinery

1,099,401. Liquid cooled dynamo-electric machines. ENGLISH ELECTRIC CO. Ltd. Feb. 23, 1965 [Feb. 28, 1964], No. 8329/64. Heading H2A. In a dynamo electric machine having a liquid, e.g. water cooled rotor, wherein the liquid is exhausted through an outlet path which includes one or more radial or substantially radial ducts 15, 16 in the rotor, such path includes means for so restricting the liquid flow in the or each duct that when the rotor is rotating the duct(s) are not full of liquid, whereby they have substantially no pumping effect on the liquid. This prevents cavitation of liquid in an axial duct 11, and as shown there is a restrictor means 21 having an orifice 22 secured to the entrance of each radial duct 15, 16, but in a modification a single restrictor unit may be positioned in the duct 11 and have orifices aligned with each radial duct. The ducts have corrosion resistant liners 12, 14 and the liquid, flowing in the direction of arrows 13, 17, passes into a collector box 18 which is sealed from the rotor shaft 10 by compressed air or gas fed through pipes 25, 26 to chambers 29, 30 in seals 27, 28.