摘要:
In a process for injecting a fine-grain carbon carrier including ash-bearing bituminous or hard coal into a blast furnace hearth, use is made of a mix of fine-grain bituminous coal and at least one other solid fine-grain ash-bearing carbon carrier. The composition of the mix is so selected that the degree of basicity of the overall resulting ash of the mixture is adapted to the degree of basicity of the furnace slag.
摘要:
A system for treating, normally refining, a metallurgical melt has a melt-containing vessel having below the level of the melt an at least gas-pervious wall portion. A finely divided treatment solids is suspended in a treatment gas and this suspension is introduced through the pervious wall portion into the melt and reacting the melt with the gas and solids. The wall portion has openings oriented so that the gases and particles can pass into the vessel through them, but the molten metal therein cannot enter them. A plurality of such gas-and particle-pervious inserts are provided in the base of the crucible. They can be individually controlled relative to respective sensors provided above the melt. Thus exothermically reacting gases and/or particles are fed in under cold spots, or endothermically reacting gases and/or particles are fed in under hot spots.
摘要:
Molten metal is introduced in a continuous-casting system downwardly into a mold through a nozzle opening downwardly into the mold at an axis to form in the mold a body of molten metal having an upper surface carrying impurities above the mouth of the mold. The body of molten metal is rotated about the axis in the mold. The nozzle is provided generally at the level of the upper surface of the body of molten metal with radially outwardly projecting vanes that prevent the body from rotating about the axis at the upper surface, thereby preventing inclusions from being sucked into the body of molten metal.
摘要:
Slag sand and slag wool are formed by a method wherein molten slag is poured at a temperature above 1300.degree. C. in a thin flowing stream onto a vaned drum rotating at a peripheral speed of at least 25 m/sec. This drum, which may have forwardly directed nozzles for mixing the falling slag stream with a cooling medium such as water, breaks the slag up into droplets and projects these droplets through the air so they cool and form filaments and granules. The granules are collected separately from the filaments so that the installation simultaneously produces slag sand and slag wool.
摘要:
Slag is conditioned during blowing from above with oxygen of an iron melt by bubbling an inert gas into the melt from the bottom of the crucible in response to measurements made of the flowability of the slag layer and the speed of decarburization.
摘要:
A method of and a device for the shipping of hot metal goods, such as hot steel ingots and slabs, in which the ingots or slabs are lowered into a container in which a granular insulating material, preferably porous vermiculite, is fluidized by a pressurized gas during the introduction of these metal goods. The particles of the insulating material, upon termination of the fluidization are then allowed to pack around and envelop the metal goods. The insulating material is again fluidized during withdrawal of the metal goods at the unloading site.
摘要:
A construction element comprises a wide-flange steel beam having a web-flange thickness ratio of at least 0.8. Anchors or holding members in the form of studs or wire fabric are secured only to the web of the beam, and a reinforcing bar or plate extending along the beam is in turn welded to the achoring members. The area between the flanges of the beam is then filled with a concrete body in which the holding members and reinforcing elements are embedded for fire resistance.
摘要:
A blowing lance for refining metals by blowing a gas onto a surface of a metal bath is presented. This lance has an adjustable tuyere for generating a supersonic refining gas flow and a blowing head with a set of fixed tuyeres opening into a front dome of the blowing head and dividing the supersonic gas flow into individual free jets. A cyclic modulator modulates a flow rate through the set of fixed tuyeres so that the flow rate in a first subset of tuyeres does not vary synchronously with the flow rate in a second subset of tuyeres, i.e., the flow rates in both subsets of tuyeres increase or decrease at the same time and they do not reach their minimum value or their maximum value at the same moment.
摘要:
In antiseismic steel structural works of the frame type or of the truss type, which are constituted by columns and by girders fastened to the columns, the girders of different shapes show, at least in the vicinity of one of their extremities, a dissipative zone constituted by a reduction of the actual cross section. The reduction of the actual cross section consists either in differently shaped indentations in the edges of the flanges of the girder or in round or polygonal holes which are regularly distributed over the flanges and have a small diameter.