外文翻译--轧钢工业的发展

附 录附录A：英文原文The development of steel industryRolling industrial development of China's small and medium-sized steel industry with the development of socialist construction, great changes have taken place. At present, the provinces have established a regional rolling production system, in production,construction play its due role. Small and medium-sized iron and steel enterprises rolling production systems its basic composition workshop figure l-1 below. From the map you can see that This system consists of 650 rolling medium (steel) mill (including 630 650 × 3, 650 × 1 / 500 550 × 3 and other types); 500/350 small (steel) mill (including 500 × 2, 500 × 2 / 300 350 × 54 × 5 X2/300. 300 × 2 / 250 × 155 × 5, and other types); 76 or 100 mm Seamless Steel Tube Mill; 1200 mm roll sheet mill; 2300 - mm plate mill (including tandem-seat units), and wire, tropical, cold zone, and other mill. In order to expand and improve varieties of steel mill products (such as 650 medium-sized mill, etc.) production capacity, in the Mid-qualified minority may consider additional 750 850 medium Mill. Above this rolling steel production systems' full range of materials that can adapt to the development of local industrial needs. Several of these are by small and medium-sized mill, a short presentation features are as follows : 50 medium (steel) mill in the small and medium-sized iron and steel joint enterprises mainly for the opening production of billet and steel medium. Generally as raw materials in steel ingot, billet rolling into, as a system of blooming machine, it has produced thin slab sheet supply roll mill, the small supply pipe Seamless Steel Tube Mill, Billet supply of small steel mill and wire mill, in addition also some medium-sized steel production. Therefore, 650 medium mill in rolling system plays an important role, it plays a steelmaking and rolling the link between role It determines the output of steel production enterprises throughout the decisive link. My Mill such a large number of widely distributed, more complex specifications also sum up, a typical comparison of the following categories : 630-650 × 3 types such mill mill for most of Blooming and simple section of the rolling radius of steel, Only individual profiled steel rolling plant more. The main problem for small mills, steel rolling and light, the roll over of these products with the required number of pass. Therefore, we can not use a rolling into a steel ingot, billet must first open (according to different products, first rolling into the fire first section of the 150 mm × 150% of the billet, or rectangular beam blank blank) rolled. that is rolling into two, it will not only low yields, and rolling processes to do it twice, which increased consumption of the metal. Moreover, due to less rack, roll groove layout is not ideal, when slot wear without reserve Kong will be forced to change roller, This is a waste of roll, but also affect the rate of mill operations. In addition, the intermediate crop shear difficult layout, and does not help with a heating Ingot. Also, when the three seat by a motor, As the planes roller mill can speed the workpiece with the extended incremental also affected the mill productivity. But such mill equipment and plant investments than two-slightly less (referring to a single drive), being easier to get started, it can satisfy, the management, all types of sheet steel billet production needs. As a medium current Blooming workshops, prefer to use this type of mill can be. If the appropriate conditions for the billet of large and medium-sized iron and steel joint ventures, This mill can be as steel mill for the production of medium-sized steel.650 × 1/500-550× 3 mill types such specialized mill Blooming, and it has to come mainly Blank, and part of the steel production. Compared with 630 -650 × 3 1 mill, more a mill, intermediate crop shear can be installed in the series between the two machines, flow more smoothly, and is conducive to a well-used steel ingot. The two machines - the main rooms can be located with the main span of the side over a double-drive mill ventilation conditions are better. When Blank to come mainly, and also to raw materials for steel ingot production of steel to meet the region's needs, may choose to use such mill. But with a heating Ingot is a certain limitations, the first intermediate billet not clear, finished surface quality are affected, straightening after more grinding, Test strict; Some plants even PV-examination, heavy workload. Secondly, the guide accidents, is not easy to control the temperature and the output affected. Certain sections of the steel complex, as workers, channels, such as deformation of the light, pass, Even two four mill did not always implement a heating Ingot. . These issues in the design would have to take into account. Parallel - small (steel) mill specifications listed in the main-500 × 2, double-500 × 2 / 350 × 5, double-400X 2 / 300 × 5,