Results 1 - 10 of 6989
Results 1 - 10 of 6989. Search took: 0.03 seconds
|Sort by: date | relevance|
[en] The main technological processes of production of big castings of austenitic and pearlitic steels for power engineering, including nuclear power engineering, are shown. It is noted that application of cast parts in the NPP equipment permits to reduce liquid metal consumption, amount of machining and to exclude welding. A great attention is paid to improvement of the reinforced casting method, for example, for the NPP gate valve casings, by way of turning the mold filled with liquid metal by 90 deg. New processes of production of molds and mold rods, and new compositions of molding sand mixtures are considered. Perspective utilization of self-set molding mixtures containing organic and nonorganic binders is noted
[en] A new construction and methods of estimation of the structural parameters of continuous casting billet machine according to the quantity of withdrawal force of hollow billets from the crystallizer's cavity are developed. It is connected with transition to continuous casting of hollow billets made of grey and high-duty cast iron with globular graphite. (author)
[en] Attempts, made for increasing quality of heavy castings for power engineering are described. Out-of-furnace modification by alloying compositions with rare earths was introduced to increase the resistance to hot-crack formation in 15Kh1M1FZ and 20KhMFZ heat-resistant steel castings. This resulted in the decrease of defect amount 1.5-2 times, decrease of brittleness temperature by 30-40 deg C and elevation of casting ductility. Steel casting technology was improved sufficiently: gating system was simplified, maximal permissible time of casting was established, the composition of mould material was determined
[en] This project on heat transfer coefficients in metal permanent mold casting has been conducted in three areas. They are the theoretical study at the University of Michigan, the experimental investigation of squeeze casting at CMI-Tech Center (Now Hayes-Lemmerz Technical Center) and the experimental investigation of low pressure permanent mold casting at Amcast Automotive
[en] This paper reports correlation of magnetic descriptors with Brinell hardness and conductivity of ductile cast iron, aiming to develop a novel nondestructive method by magnetic adaptive testing. Four series of cast iron staircase-shaped samples were investigated by this method, where different cooling rates of samples during casting resulted in different structures of each sample. The flat samples were magnetized by an attached yoke, and sensitive descriptors were obtained from a proper evaluation, based on the measurements of series of magnetic minor hysteresis loops, without magnetic saturation of the samples. Results of the nondestructive magnetic tests were compared with destructive mechanical measurements of Brinell hardness and conductivity and good correlation was found between them.
[en] At continuous casting, the quality of billet and stability of the process depend on the quality of contact between the walls of the crystallizer and the billet. Conicity of a crystallizer is one of the effective methods to provide permanent contact between the crystallizer and the billet along the whole length of the crystallizer. In the paper the influence of conicity of the crystallizer on the stretching force of the billet on the example of a round billet is shown. The results obtained are generalized to rectangular billets. (author)
[en] By controlling the cooling rates and the composition of slurries, the gradient porous hydroxyapatite ceramics are fabricated by the freeze casting method. According to the different cooling rate, the pores of HAP ceramics fabricated by gradient freeze casting are divided into three parts: one is lamellar pores, another is column pore and the last one is fine round pores. The laminated freeze casting is in favour of obtaining the gradient porous ceramics composed of different materials and the ceramics have unclear interfaces.
[en] The manifold of complex quality parameters is represented for the further development of a testing system. Selections and criteria for the industrial application and final testing are given and the process conditions are compared with plant possibilities by means of some examples. (orig.)
[de]Dargestellt wird die Vielzahl komplexer Qualitaetsparameter fuer die Weiterentwicklung eines Pruefsystems. Auswahlen und Kriterien fuer die betriebliche Anwendung und Nachkontrolle werden gegeben und die Prozessbedingungen mit den Anlagemoeglichkeiten anhand einiger Beispiele verglichen. (orig.)
[en] A casting technique has been developed for preparing multiple actinide metal disks which have a minimum thickness of 0.006 inch. This technique was based on an injection casting procedure which utilizes the weight of a tantalum metal rod to force the molten metal into the mold cavity. Using the proper mold design and casting parameters, it has been possible to prepare ten 1/2 inch diameter neptunium or plutonium metal disks in a single casting, This casting technique is capable of producing disks which are very uniform. The average thickness of the disks from a typical casting will vary no more than 0.001 inch and the variation in the thickness of the individual disks will range from 0.0001 to 0.0005 inch. (Auth.)