| ABSOLUTE PRESSURE | (english) The indicated value of the weight of the earth's atmosphere. At sea level, this value is approximately 14.65 psi (pounds per square inch). |
| ACCUMULATOR | (english) A vessel, normally cylindrical, which is used to store fluid and gas for future release of the energy in the compressed fluid and gas. Normally contains a diaphragm or piston between the fluid (liquid) and gas chambers. Fluid is normally introduced at one end and the gas at the opposite end. |
| Agglomerating Processes | (english) "Fine particles of limestone (flux) and iron ore are difficult to handle and transport because of dusting and decomposition, so the powdery material usually is processed into larger pieces. The raw material's properties determine the technique that is used by mills. 1) SINTER Baked particles that stick together in roughly one-inch chunks. Normally used for iron ore dust collected from the blast furnaces. 2) PELLETS Iron ore or limestone particles are rolled into little balls in a balling drum and hardened by heat. 3) BRIQUETTES Small lumps are formed by pressing material together. Hot Iron Briquetting (HBI) is a concentrated iron ore substitute for scrap for use in electric furnaces. |
| BACK PRESSURE | (english) The level of pressure on the return or downstream side of a device or system. |
| Back-up Roll | (english) 1) Roll used as a support roll mainly for plater rolls. 2) Two rolls, one on top and one on bottom of the two work rolls which apply pressure and reduce the flexing of the work rolls. |
| Backer (back-up plate) | (english) A “tool” or reinforcing part, which presses against the outer surface of an extrusion die, supporting it against the pressure of the extruding metal. The backer has an opening larger than the die aperture, allowing the extruded product to emerge without marring its soft surface. |
| BACKUP BOTTLE | (english) A vessel, normally cylindrical, which is used to store gas for future release of the energy in the compressed gas to an accumulator. |
| Baked Strength | (english) Compressive, shear, tensile or transverse strength of a mold sand mixture when baked at a temperature above 231 B0F (111 B0C) and then cooled to room temperature. |
| Basic Oxygen Furnace (BOF) | (english) "WHAT A pear-shaped furnace, lined with refractory bricks, that refines molten iron from the blast furnace and scrap into steel. Up to 30% of the charge into the BOF can be scrap, with hot metal accounting for the rest. WHY BOFs, which can refine a heat (batch) of steel in less than 45 minutes, replaced open-hearth furnaces in the 1950s; the latter required five to six hours to process the metal. The BOF's rapid operation, lower cost and ease of control give it a distinct advantage over previous methods. HOW Scrap is dumped into the furnace vessel, followed by the hot metal from the blast furnace. A lance is lowered from above, through which blows a high-pressure stream of oxygen to cause chemical reactions that separate impurities as fumes or slag. Once refined, the liquid steel and slag are poured into separate containers. " |
| Bearing Load | (english) A compressive load supported by a member, usually a tube or collar, along a line where contact is made with a pin, rivet, axle, or shaft. |