Improvements in or relating to apparatus for electrically heating high-pressure steam generators or high-pressure steam accumulators

摘要

629,296. Heating water by electric resistances. RUTHS INTERNATIONAL ACCUMULATORS, Ltd. (Wiener Lokomotivfabrik Akt.-Ges.). Nov. 22, 1946, No. 34725. [Class 39(iii)] [Also in Group XIII] A high-pressure steam generator or accumulator 1, Fig. 1, is heated indirectly by electric resistance elements 2 which are located within pressure-resisting tubes 3 in an external vessel 4, the said vessel being partly filled with an auxiliary liquid, e.g. water, and communicating with the two ends of a heat exchanger 5 extending through the generator 1. Steam is formed in the vessel 4 and is circulated through the exchanger 5, the condensate returning- to said vessel. In a modification, Fig. 7, the auxiliary liquid is confined within a tube 6 which projects through the end of the generator 1 and encloses an element 2, the assembly preferably being inclined so that the inner end thereof reaches to near the bottom of the generator and the tube 6 having an enlarged upper end to provide for thermal expansion of the liquid and also an adequate vapour space. A plurality of elements 2 with their protective tubes 3 may be located within a single enclosing tube 6, and, preferably, the tubes 3 have a greater factor of safety against breakdown than the tube 6. The invention may be applied to a steam-accumulator locomotive, Fig. 9, in which the heating elements 8 project into the accumulator drum 1 and which, if there is an electric supply line running along the operating track of the locomotive, may be charged while the locomotive is in operation. Fig. 10 shows a charging plant for fireless locomotives comprising a stationary accumulator drum 1 with heating elements 8, a feedwater pump 13, associated with water-treating apparatus 15 and a combined de-aerator and preheater 14, and a steam outlet pipe 10 including a charging valve 11 and superheater 12.