The use of inserts made from self-hardening liquid mixtures (SLM), which make it possible to mechanize the process of lining the top part of a mold, reduces the head cutting waste of high-quality electric steel to 11-12% [i]. A further decrease in the head waste can be achieved by using exothermal inserts made from SLM. These exothermal inserts are of particular interest.In order to evaluate their behavior during metal casting, we prepared experimental tiles Of trapezoidal shape of the following dimensions: lower base, 95; upper, 60; height 65, and depth i0 mm. The composition of the tiles was 80% sand, 6% ferrochrome slag, 8% iron ore, and 6% exothermal component.To 100% of the batch, we added 7% bonding material in the form of sodium silicate water glass with a density of 1.4 g/cm 3.For the exothermal component we used aluminum (5%) plus 1% NaCI (composition No. i); FeSi iron silicide (composition No. 2); or SiCa calcium silicide (composition No. 3). The tiles were prepared by casting.To evaluate the resistance of the tiles to abrasive wear, we determined their crumbling tendency, which is characterized by the weight loss from the surface layer of a specimen per unit time when the specimen is rolled around the wall of a meshed drum rotating at a frequency of 60 rpm. The properties of the tiles are given in Table i.Tool (U7A) and bearing (ShKhlS) steels were melted in a 50-kg induction furnace and cast in square molds with the head adapters lined with the experimental tiles. The clear surface of the metal was warmed with a graphite sol. The ingots were removed and cut open on an electrochemical-mechanical machine tool along the axis of the longitudinal section.

With the aim of reducing the consumption of chamotte brick and possible mechanization of lining operations, the Zaporozhe Industrial Institute, in collaboration with the ' Zaporozhstal'" Works, has made industrial tests on monolithic linings of steel-tapping runners made of chrome--magnesite compound.At present the steel-tapping runners at the Zaporozhstal' Works are laid with chamotte bricks, of which the specific consumption is about 1.4 kg/ton steel. To protect the masonry from the action of fused metal and slag, it is covered with a layer of chamotte--clay--coke compound. However, the high open porosity (39.~7o) and low compressive strength (2.5 MPa) of the coating do not satisfy the service conditions of the lining. During tapping the fused steel erodes the protective coating and the lining. Moreover, the metal and slag stick to the masonry.

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Дніпропетровський національний університет імені Олеся Гончара ПОБУДОВА ПОВЕРХОНЬ ЗА ДОПОМОГОЮ ТЕХНОЛОГІЇ T-СПЛАЙНІВПроведено огляд та порівняльний аналіз сучасних методів побудови поверхонь, а саме Т-сплайнів і NURBS. Розглянуто основні риси Т-сплайнів, їхні особливості, переваги та недоліки.Ключові слова: NURBS поверхні, Т-сплайни, локальне уточнення.Проведен обзор и сравнительный анализ современных методов построения поверхностей, а именно Т-сплайнов и NURBS. Рассмотрены основные черты Т-сплайнов, их особенности, преимущества и недостатки.Ключевые слова: NURBS-поверхности, Т-сплайны, локальное уточнение.It was maked a review and comparative analysis of modern methods of building of surfaces, namely, T-Splines and NURBS. Also was considered the main features, characteristics, advantages and disadvantages of T-Splines.