| The following anecdote was told to myself, a few months after the curious event, by the three witnesses in the case. They were connections of my own, the father was a clergyman of the Anglican Church; he, his wife and their daughter, a girl of... Read more of The Girl In Pink at Scary Stories.ca |  InformationalPrivacy |
Steel MakingRefining The GrainThis is remedied by reheating the piece to a temperature slig... Silicon Silicon prevents, to a large extent, defects such as gas bubb... Judging The Heat Of Steel While the use of a pyrometer is of course the only way to hav... Carbon-steel Forgings Low-stressed, carbon-steel forgings include such parts as car... Suggestions For Handling High-speed Steels The following suggestions for handling high-speed steels are ... An Automatic Temperature Control Pyrometer Automatic temperature control instruments are similar to the ... Pyrometry And Pyrometers A knowledge of the fundamental principles of pyrometry, or th... Gas Consumption For Carburizing Although the advantages offered by the gas-fired furnace for ... Robert Mushet Robert (Forester) Mushet (1811-1891), born in the Forest of D... Silicon SILICON is a very widespread element (symbol Si), being an es... Tool Or Crucible Steel Crucible steel can be annealed either in muffled furnace or b... Making Steel Balls Steel balls are made from rods or coils according to size, st... Annealing Alloy Steel The term alloy steel, from the steel maker's point of view, r... Effects Of Proper Annealing Proper annealing of low-carbon steels causes a complete solu... Annealing Of High-speed Steel For annealing high-speed steel, some makers recommend using g... Hardening Operation Hardening a gear is accomplished as follows: The gear is tak... Case-hardening Treatments For Various Steels Plain water, salt water and linseed oil are the three most co... The Modern Hardening Room A hardening room of today means a very different place from ... A Chromium-cobalt Steel The Latrobe Steel Company make a high-speed steel without tun... Annealing There is no mystery or secret about the proper annealing of d... |
Pyrometry And PyrometersCategory: PYROMETRY AND PYROMETERS A knowledge of the fundamental principles of pyrometry, or the measurement of temperatures, is quite necessary for one engaged in the heat treatment of steel. It is only by careful measurement and control of the heating of steel that the full benefit of a heat-treating operation is secured. Before the advent of the thermo-couple, methods of temperature measurement were very crude. The blacksmith depended on his eyes to tell him when the proper temperature was reached, and of course the color appeared different on light or dark days. Cherry to one man was orange to another, and it was therefore almost impossible to formulate any treatment which could be applied by several men to secure the same results. One of the early methods of measuring temperatures was the iron ball method. In this method, an iron ball, to which a wire was attached, was placed in the furnace and when it had reached the temperature of the furnace, it was quickly removed by means of the wire, and suspended in a can containing a known quantity of water; the volume of water being such that the heat would not cause it to boil. The rise in temperature of the water was measured by a thermometer, and, knowing the heat capacity of the iron ball and that of the water, the temperature of the ball, and therefore the furnace, could be calculated. Usually a set of tables was prepared to simplify the calculations. The iron ball, however, scaled, and changed in weight with repeated use, making the determinations less and less accurate. A copper ball was often used to decrease this change, but even that was subject to error. This method is still sometimes used, but for uniform results, a platinum ball, which will not scale or change in weight, is necessary, and the cost of this ball, together with the slowness of the method, have rendered the practice obsolete, especially in view of modern developments in accurate pyrometry. Next: Pyrometers Previous: Furnace Data
Viewed 827 |
||||||||||||||||||||
