| BAOSHAN IRON & STEEL CO., LTD. Patent applications |
| Patent application number | Title | Published |
| 20120000262 | METHOD FOR MANUFACTURING GRAIN-ORIENTED SILICON STEEL WITH SINGLE COLD ROLLING - The invention provides a method for producing grain-oriented silicon steel with single cold rolling, comprising: 1) smelting, refining and continuous casting to obtain a casting blank; 2) hot rolling; 3) normalization, i.e. normalizing annealing and cooling; 4) cold-rolling, i.e. single cold rolling at a cold rolling reduction rate of 75-92%; 5) decarburizing annealing at 780-880° C. for 80-350 s in a protective atmosphere having a due point of 40-80° C., wherein the total oxygen [0] in the surface of the decarburized sheet: 171/t≦[O]≦313/t (t represents the actual thickness of the steel sheet in mm), the amount of absorbed nitrogen: 2-10 ppm; 6) high temperature annealing, wherein the dew point of the protective atmosphere: 0-50° C., the temperature holding time at the first stage: 6-30 h, the amount of absorbed nitrogen during high-temperature annealing: 10-40 ppm; 7) hot-leveling annealing. The invention may control the primary recrystallization microstructure of steel sheet effectively by controlling the normalization process of hot rolled sheet to form sufficient favorable (Al, Si)N inclusions from nitrogen absorbed by slab during decarburizing annealing and low-temperature holding of high-temperature annealing, facilitating the generation of stable, perfect secondary recrystallization microstructure of the final products. In addition, the invention avoids the impact of nitridation using ammonia on the underlying layer in prior art, and thus the formation of a good glass film underlying layer is favored. | 01-05-2012 |
| 20110180187 | METHOD FOR PRODUCING GRAIN-ORIENTED SILICON STEEL CONTAINING COPPER - A method of manufacturing oriented Si steel containing Cu with high electric-magnetic property comprises: hot rolling slab; after first cold rolling, heating it to 800° C. or higher temperature and performing intermediate decarburization annealing in a protective atmosphere with P | 07-28-2011 |
| 20110139313 | MANUFACTURING METHOD OF ORIENTED SI STEEL WITH HIGH ELECTRIC-MAGNETIC PROPERTY - A manufacturing method of oriented Si steel with high electric-magnetic property comprises the following steps: smelting steel in converter or electric furnace; refining molten steel in two stages; continuous casting to obtain slab; hot rolling; first cold rolling; decarburizing annealing; secondary cold rolling; applying an annealing separator based on MgO and annealing at high temperature; applying an insulating coating and leveling tension annealing. The slab comprises (in wt %): C 0.020-0.050%, Si 2.6-3.6%, S 0.015-0.025%, Als 0.008-0.028%, N 0.005-0.020%, Mn 0.15-0.5%, Cu 0.3-1.2%, balance Fe and inevitable impurities, in which 10≦Mn/S≦20 and Cu/Mn≧2. The method could produce oriented Si steel with high magnetic induction intensity and low iron loss at low cost. | 06-16-2011 |
| 20100032062 | STEEL PLATE HAVING A LOW WELDING CRACK SUSCEPTIBILITY AND A YIELD STRENGTH OF 800MPa AND MANUFACTURE METHOD THEREOF - The present invention provides a steel plate having a low welding crack susceptibility and a yield strength of 800 MPa and a manufacturing method for the same. The steel plate having a low welding crack susceptibility comprises the following chemical components (wt. %: percent by weight): C: 0.03-0.08 wt. %, Si: 0.05-0.70 wt. %, Mn: 1.30-2.20 w.t %, Mo: 0.10-0.30 wt. %, Nb: 0.03-0.10 wt. %, V: 0.03-0.45 wt. %, Ti: 0.002-0.040 wt. %, Al: 0.02-0.04 wt. %, B: 0.0010-0.0020 wt. %, the balance being Fe and unavoidable impurities, and the welding crack susceptibility index meets the following formula: Pcm≦0.20%. The thermo-mechanical controlled rolling and cooling processes is used to obtain an ultrafine bainite batten matrix structure, which increases the intensity, plasticity and toughness of the steel plate. The steel plate with a low welding crack susceptibility of the present invention has a yield strength of greater than 800 MPa, a tensile strength of greater than 900 MPa, a Charpy impact energy Akv (−20° C.) of no less than 150 J and an excellent welding performance. | 02-11-2010 |
| 20080272526 | Steel Slag Treatment Equipment by Barrel Method - This invention relates to metallurgical slag treatment equipments. A double cavity type steel slag treatment equipment by barrel method employing mandrel support comprises left and right barrel bodies, flow branching pan, mandrel, feed funnel. Between the left and right barrel bodies is disposed a flow branching pan, over which is mounted a feed funnel and below which is mounted a retaining ring. The mandrel is fixedly connected to the left and right barrel bodies and flow branching pan, characterized is that at two ends of the mandrel are mounted supporting bearings, left and right barrel bodies have inner and outer portions, inner barrel body is made of grid section, one end of grid section is fixed on the end cover of outer barrel body through an insertion opening made of supporting rings, the other end of grid section is joined with the supporting ring fixedly connected on outer barrel body, the mandrel fixedly connects outer barrel body, outside the outer barrel at one side is mounted a geared ring for transmitting force moment the geared ring is fixedly connected with outer barrel body. The invention can cool slag material sufficiently, improve performance of product slag, reduce weight of equipment, decrease cost and increase the space available for maintenance and repair. | 11-06-2008 |