COOLING WATER PIPING DEVICE FOR ELECTRIC APPARATUS

摘要

PURPOSE: To provide a piping joint capable of preventing a water leakage accident by suppressing the electrolytic corrosion of a part for connecting an electrical insulating pipe to a metallic joint of a cooling water piping for electric apparatus. CONSTITUTION: The electrolytic corrosion is suppressed if the flow velocity of cooling water on the surface of the wetting part 24a of the piping joint 4 is increased and, therefore, a flow passage constricting body 26 is arranged at the center of the flow passage section of the piping joint 4 to reduce the flow passage section of the pipeline and to accelerate the flow velocity of the part at the metallic end shown by a region Z2. This flow passage constricting body 26 is composed of an insulator so as not to affect a potential distribution and is fixed to the inner side of a mounting seat 24 by a fixing plate 27. The region Z1 of the metallic pipeline exclusive of a metallic end and the range of the electrical insulating pipeline Z3 exclusive of a juncture are large in the flow passage section and low in the flow velocity and, therefore, the pressure drop is low. The pressure increase of the entire part of the system is thereby suppressed low.