Pramod Batheja

Design and testing of the reactor-internal hydraulic control rod drive for the nuclear heating plant

A hydraulically driven control rod is being developed at Kraftwerk Union for integration in the primary system of a small nuclear district heating reactor. An elaborate test program, under way for --3 yr, was initiated with a plexiglass rig to understand the basic principles. A design specification list was prepared, taking reactor boundary conditions and relevant German rules and regulations into account. Subsequently, an atmospheric loop for testing of components at 20 to 90/sup 0/C was erected. The objectives involved optimization of individual components such as a piston/cylinder drive unit, electromagnetic valves, and an ultrasonic position indication system as well as verification of computer codes. Based on the results obtained, full-scale components were designed and fabricated for a prototype test rig, which is currently in operation. Thus far, all atmospheric tests in this rig have been completed. Investigations under reactor temperature and pressure, followed by endurance tests, are under way. All tests to date have shown a reliable functioning of the hydraulic drive, including a novel ultrasonic position indication system.

Design aspects and pertaining development work for the KWU 200 MWth nuclear heating reactor

Abstract In many countries great efforts are being made to use nuclear energy for district heating. KWU, too, has developed a dedicated nuclear heating reactor based on the experience gained with its light water reactors. Beyond the overall goal of a high degree of safety, it was most essential that the development should achieve its economic goal. Both goals can be achieved by an integrated light water reactor working at a modest pressure of 15 bar and a temperature of 200°C. Though light water technology is well known, some development fields were identified which needed specific work. These areas are the primary system mechanical design, the integrated hydraulic control rod drive, and extensive studies on the thermohydraulic stability of the primary system as well as transient analyses.