 Prays - Download the EBook Bible Myths |  InformationalPrivacy |
Steel MakingRate Of CoolingAt the option of the manufacturer, the above treatment of gea... Hardness Testing The word hardness is used to express various properties of me... Compensating Leads By the use of compensating leads, formed of the same materia... Chromium Chromium when alloyed with steel, has the characteristic func... Heating Of Manganese Steel Another form of heat-treating furnace is that which is used ... For Milling Cutters And Formed Tools FORGING.--Forge as before.--ANNEALING.--Place the steel in a ... Pyrometry And Pyrometers A knowledge of the fundamental principles of pyrometry, or th... Temperatures To Use As soon as the temperature of the steel reaches 100 deg.C. (... Heat Treatment Of Lathe Planer And Similar Tools FIRE.--For these tools a good fire is one made of hard foundr... Tempering Round Dies A number of circular dies of carbon tool steel for use in too... Non-shrinking Oil-hardening Steels Certain steels have a very low rate of expansion and contract... Open Hearth Process The open hearth furnace consists of a big brick room with a l... Annealing Work With the exception of several of the higher types of alloy s... Properties Of Alloy Steels The following table shows the percentages of carbon, manganes... Annealing Of Rifle Components At Springfield Armory In general, all forgings of the components of the arms manufa... Refining The Grain This is remedied by reheating the piece to a temperature slig... Gears The material used for all gears on the Liberty engine was sel... Hardening High-speed Steels We will now take up the matter of hardening high-speed steels... Plant For Forging Rifle Barrels The forging of rifle barrels in large quantities and heat-tre... Sulphur SULPHUR is another element (symbol S) which is always found i... |
Crucible SteelCategory: STEEL MAKING Crucible steel is still made by melting material in a clay or graphite crucible. Each crucible contains about 40 lb. of best puddled iron, 40 lb. of clean mill scrap--ends trimmed from tool steel bars--and sufficient rich alloys and charcoal to make the mixture conform to the desired chemical analysis. The crucible is covered, lowered into a melting hole (Fig. 4) and entirely surrounded by burning coke. In about four hours the metal is converted into a quiet white hot liquid. Several crucibles are then pulled out of the hole, and their contents carefully poured into a metal mold, forming an ingot. If modern high-speed steel is being made, the ingots are taken out of the molds while still red hot and placed in a furnace which keeps them at this temperature for some hours, an operation known as annealing. After slow cooling any surface defects are ground out. Ingots are then reheated to forging temperature, hammered down into billets of about one-quarter size, and 10 to 20 per cent of the length cut from the top. After reheating the billets are hammered or rolled into bars of desired size. Finished bars are packed with a little charcoal into large pipes, the ends sealed, and annealed for two or three days. After careful inspection and testing the steel is ready for market. Next: The Electric Process Previous: Open Hearth Process
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