Simulation versus calculation

Calculation is the common method to analyze production rates. An idealized model of the plant, consisting of a number of its individual components, is first created. In the rolling mill, these components are the furnace, rolling stands, cooling bed, etc. Following the creation of the model, the production rate of each individual component is calculated for each product. The component with the lowest throughput becomes the bottleneck and determines the throughput of the entire mill by product.

Simulation, in comparison, attempts to reflect the exact behavior of the mill for any given scenario. A model is created that contains all of the equipment and processes in the mill. Modeling and implementation of the logic and rules are the tasks to be performed in this approach.

Simulation is replacing calculation for the analysis of minimill production and operations for many reasons including:

Limitations of calculation approach - The drawback of this method is that the mill components are considered independently, and an idealized model does not represent all of the important details and interactions of the real mill.

Reliability of results - simulation results are more reliable than calculation results due to logical approach of the method. Simulation results have greater accuracy and therefore are economically more efficient.

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Physical Metallurgists

Physical metallurgists are responsible for developing new aluminium alloys that reduce weight and improve the fuel efficiency of aircraft, automobile steel that offer excellent properties without expensive heat treatments, and nickel superalloys that operate safely at high temperatures. The physical metallurgists, studies the behavior of metals and their alloys, in order to characterize their internal structure, or microstructure; to understand how the microstructure influences the properties or the metal and to develop new and improved alloys. The physical metallurgist often uses sophisticated instruments to understand the structure and properties of metals. With the electron microscopes, the physical metallurgist can directly observe very tiny features of the microstructure and learn how these features influence the metal's behavior. With such instruments even the arrangement of individual atoms in the metal can be observed.

The physical metallurgist develops strengthening mechanisms based on the micro-structural features in the metal. Strength can be increased by controlling the atomic structure in the metal, deforming the metal, or adding alloys. Heat treatment of alloyed metal can often significantly improve us strength. In a number of metal systems, heat treatments can produce complicated microstructures that prevent even very large cracks from growing. These metals may allow airplanes to safely operate with small cracks until the cracks are discovered and repaired.

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The replacement of charcoal

By the 17th century coke was beginning to replace charcoal as the primary blast-furnace fuel. Made from coal, which was just coming into use in Europe, coke produced higher temperatures than charcoal, and its greater strength permitted larger, heavier charges and the use of larger, more efficient furnaces.

In the United States, with its abundant forests, charcoal continued to be the main furnace fuel until about 1840, when anthracite coal came into use. Coke became the prime fuel only in the 1870s and '80s, and large coke-making facilities soon became necessary adjuncts to the blast furnace.

Little change in blast-furnace technology took place until the 1830s, when it was found that heating the air blast before blowing it into the furnace greatly increased furnace efficiency. The construction of the furnace also changed. The square-based stone stack was replaced by a tall, cylindrical structure made of wrought-iron plates and lined with firebrick. These larger furnaces increased the production of iron considerably. In 1839 the new-style furnaces were reportedly able to produce 28 tons of iron in a week. Stone-structure furnaces were limited to half that tonnage. By 1900 furnaces had grown even larger and were capable of producing more than 200 tons of molten iron per day. During the 20th century significant improvements in blast-furnace structure and practice (but not in the basic process) have resulted in tremendous production increases.

Література

1. В.Н. Бгашев, Е.Ю.Долматовская « Английский язык для студентов машиностроительных специальностей», Москва, Астрель, АСТ, 2005.

2. И.П.Агабекян, П.И.Коваленко « Английский для технических ВУЗов», Ростов-на-Дону, Феникс, 2005

3. Л.М.Черноватий, В.І.Карабан « Переклад англомовної технічної літератури», Нова Книга, Вінниця, 2006

4. Є.О.Мансі « English» тексти,для студентів інженерних, аграрних, медичних вищих навчальних закладів, Київ, В.ц. «Академія», 2004

5. Інтернет джерела.

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