Vacuum Arc Remelting - A process used for producing advanced steels to the most demanding and critical specifications, paarticularly in such areas as aerospace applications. The steel is first produced to a very close analysis and the resulting ingot is sl -
Vacuum - A negative pressure that pulls the exhaust steam out of a turbine.
Vacuum Annealing - Vacuum is best characterized as a lack of atmosphere (i.e. air,oxygen or other gases). Hence when metals or alloys are heated to high temperatures in a vacuum furnace, there is essentially no oxygen present to oxidize and discolor the surface of the material. Unfortunately, vacuum annealing is not condusive to strand annealing (i.e. uncoiling, heating and recoiling). Titanium rolled Ulbrich is annealed in coil form in vacuum furnaces by outside heat treaters.
Vacuum Breaker - A valve used to break the vacuum on the exhaust of a turbine.
Vacuum Casting - A casting in which metal is melted and poured under very low atmospheric pressure; a form of permanent mold casting where the mold is inserted into liquid metal, vacuum is applied, and metal drawn up into the cavity.
Vacuum Degassing - An advanced steel refining facility that removes oxygen, hydrogen and nitrogen under low pressures (in a vacuum) to produce ultra-low-carbon steel for demanding electrical and automotive applications. Normally performed in the ladle, the removal of dissolved gases results in cleaner, higher-quality, more pure steel
Vacuum Oxygen Decarburization (VOD) - "WHAT Process for further refinement of stainless steel through reduction of carbon content. WHY The amount of carbon in stainless steel must be lower than that in carbon steel or lower alloy steel (i.e., steel with alloying element content below 5%). While electric arc furnaces (EAF) are the conventional means of melting and refining stainless steel, VOD is an economical supplement, as operating time is reduced and temperatures are lower than in EAF steelmaking. Additionally, using VOD for refining stainless steel increases the availability of the EAF for melting purposes. HOW Molten, unrefined steel is transferred from the EAF into a separate vessel, where it is heated and stirred by an electrical current while oxygen enters from the top of the vessel. Substantial quantities of undesirable gases escape from the steel and are drawn off by a vacuum pump. Alloys and other additives are then mixed in to refine the molten steel further. "
Vacuum Refining - Melting in a vacuum, usually by electrical induction, to remove gaseous contaminants from the metal.
Vanadium - Chemical symbol V. Element No. 23 of the periodic system; atomic weight 50.95. Gray-white, hard metal, unaffected by atmospheric influences or alkalis but soluble in most strong acids; melting point 3119 (degrees) F.; boiling point about 6150 (degrees) F.; specific gravity 5.87. It cannot be electrodeposited. Its principal functions as an alloy in the making of tool steels. (1) Elevates coarsening temperature of austenite (promotes fine grain). (2) Increases hardenability (when dissolved) (3) Resists tempering and causes marked secondary hardening.
Varnish - A colorless, transparent finish applied over a decorative system to protect the substrate and inks and improve gloss.
VARS - (or KVAR) Unit used to measure the part of the electrical power that is used to magnetize the iron in an electrical motor or transformer so that the motor or transformer will work. You get no work output from VARS, but they are always in the circuit.
Vegetable Oils - Oils extracted from plants, used as drying oils in oil core manufacture. Linseed oil is an example.
Veins - A discontinuity on the surface of a casting appearing as a raised, narrow, linear ridge that forms upon cracking of the sand mold or core due to expansion of the sand during filling of the mold with molten metal.
Vent Mark - A small protrusion on a forging resulting from the entrance of metal into a die vent hole.
Venting - Perforation with a vent wire of the sand over and around a mold cavity to assist in the escape of the gases.
Venturi Throat Dampers - North and South. Common to both boilers.
Venturi Valve - Valve that contains nozzled openings arranged in a 360 B0 pattern, which is often referred to as a doughnut due to its shape. Water is fed through the Venturi at a high-pressure level and the water flow develops suction on the line that can be used for various purposes.
Venturis - Perform the primary scrubbing of waste gases, by introducing water to waste heat gases.
Vertical Axis Casting Machine - A centrifugal casting machine in which the axis of rotation of the mold is vertical.
Vessel Cover - (also called 'Hood') Section of the boiler tubes that are located directly over the steel making vessel. The tubes are in the entry area of the heat and waste gases during steel making.
Vibrator Reed Steel - Hardened, tempered and white polished wxtra precision rolled. Carbon content about 1.00. Steel must withstand great fatigue stresses.
Vicers Diamond Pyramid Hardness Tester - Patented indentation hardness machine. See Hardness
Vickers Hardness (Test) - Standard method for measuring the hardness of metals, particularly those with extremely hard surfaces; the surface is subjected to a standard pressure for a standard length of time by means of a pyramid shaped diamond. The diagonal of the resulting indention is measured under a microscope and the Vickers Hardness value read from a conversion table.
Vinyl - Vinyl resins are copolymers with vinyl chloride and vinyl acetate as the major film formers. They offer toughness, flexibility, and adhesion and are considered flavor-free.
Vinyl Alkyd - A type of resin consisting of a physical mixture of vinyl with alkyd to improve performance characteristics such as flexibility.
Virbrator - A device, operated by compressed air of electricity, for loosening and withdrawing patterns from a mold, or for vibrating a hopper or chute to promote the flow of material from the hopper or chute.
Viscosity - The resistance of fluid substance to flowing, quantitatively characteristic for an individual substance at a given temperature and under other definite external conditions.
Void - A shrinkage cavity produced in casting during solidification.
Volt - Unit of measurement that describes the difference in potential between two points in a circuit. The greater the difference in potential, the more push the electrons that are flowing in the circuit have.
Voluntary Restraint Agreements (VRAs) - A compromise reached between the U.S. government and foreign steel-exporting nations. Instead of the United States imposing punitive duties on subsidized steel imports, the foreigners would "voluntarily" limit their steel exports to the United States.
Voss - Leveler on all three galvanizing lines; series of rolls that flatten the strip.
Voss Leveler - A set of rolls that flattens and stretches the strip into a flat shape.
Vacancy - A type of structural imperfection in which an individual atom site is temporarily unoccupied.
Vacuum Melting - Melting in a vacuum to prevent contamination from air, as well as to remove gases already dissolved in the metal; the solidification may also be carried out in a vacuum or at low pressure.
Veining - A type of sub-boundary structure that can be delineated because of the presence of a greater-than-average concentration of precipitate or solute atoms.
Virgin Metal - Metal obtained directly from ore and not used before.