[en] Heat exchangers of high quality and operational safety can only be fabricated economically if fabrication is as 'simple' as possible and can be controlled and if, through value analysis, the work flows can be mechanized and automated and the following requirements are met: use of materials that are easy to work with for the application considered, choice of product designs and wall thicknesses that offer favourable conditions for processing and non-destructive testing, placing of seams in such a way that good accessibility for welding and minimum residual welding stresses are assured, minimizing the number of welding seams, use of automatic welding machines for submerged-arc welding and electronically controlled sources of welding current - semi-automatic equipment for spatter-free interfaces (pulse technique), electronically controlled equipment for welding in rollers and pipes and CNC-controlled machining centres for drilling pipe galleries (deep-hole drilling) and baffle plates and for machining the sealing elements after welding. Continuous inspections in each phase of fabrication assures that heat exchangers are made which fully meet the requirements of nuclear power station operators. (orig.)

[en] Plasma processing is used for producing new materials with unusual and superior properties, for developing new chemical compounds and processes, for machining, and for altering and refining materials and surfaces. It has direct applications to semiconductor fabrication, materials synthesis, welding, lighting, polymers, anti-corrosion coatings, machine tools, metallurgy, electrical and electronics devices, hazardous waste removal, high performance ceramics, and many other items in both high-technology and the more traditional industries. Plasma processing takes on a wide variety of apparently different forms in industry, but the techniques share many common characteristics and problems. Control of the generation and flux of ions, electrons and free radicals in the plasma and their incidence on a surface is vital. Diagnostics, sensors, modeling techniques, and associated statistical methods are needed. However, without an in-depth understanding of the variety of phenomena taking place and their application to the industrial environment, advances in this technology, and its efficient use, will occur at a diminishing rate

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[en] A grid of a fuel assembly structure for a nuclear reactor comprises two sets of uniformly spaced straps perpendicular to each other for receiving and supporting cylindrical sleeves. The straps forming cells which receive the sleeves have notches at their edges, and the sleeves are joined to the straps by lap welding at the notches

[en] Two vertical shafts, the upper driving shaft and the lower driven shaft, are coupled by a device comprising a small diameter shaft locked with the lower shaft with grooves allowing sliding. The invention is applied for suspended bowl centrifuges and for centrifuge pendular mixer settlers used for clarification of radioactive nitric solutions from spent fuel dissolution

[en] A process and means are provided for forming or bonding a liner to a shell or element wherein the liner is filled with or immersed in water and a portion of the water is frozen

[en] The storage ring vacuum system for the Pohang Light Source (PLS) has been designed to maintain the vacuum pressure of 10^₁0Torr which requires UHV welding to have helium leak rate less than 1x10^₁0Torr·L/sec. In order to develop new technique (PLS) welding technique), a prototype vacuum chamber has been welded by using Tungsten Inert Gas welding method and all the welded joints have been tested with a non-destructive method, so called helium leak detection, to investigate the vacuum tightness of the weld joints. The test was performed with a detection limit of 1x10^₁0Torr·L/sec for helium and no detectable leaks were found for all the welded joints. Thus the performance of welding technique is proven to meet the criteria of helium leak rate required in the PLS Storage Ring. Both the principle and the procedure for the helium leak detection are also discussed