60results about How to "Raise the finishing temperature" patented technology

The invention discloses a method for producing a 65Mn hot rolled steel plate, which comprises the steps of smelting, refining, thin slab casting, soaking, high pressure water descaling, hot continuous rolling, cooling and reeling based on the process of thin slab casting and rolling. The molten steel superheat temperature is T superheat (30 DEG C <T superheat < / = 45 DEG C), the charging temperature of casting blanks is T charging (900 DEG C < / = T charging < / = 1050 DEG C), the final rolling temperature is T final (850 DEG C < / = T final < / = 950 DEG C), the reeling temperature is T reeling ( 550DEG C < / = T reeling < / = 650 DEG C), the liquid core pressure of casting blanks is L pressure (2 < / = L pressure < / = 20mm), and the depth of a single-surface decarburized layer is 0.3 to 0.9 percent ofthe depth of the steel plate. The chemical constitutes of molten steel after being alloyed in a refining process comprise 0.62-0.70 wt.% of C, 0.17-0.37 wt.% of Si, 0.90-1.20 wt.% of Mn, less than orequal to 0.035 wt.% of P, less than or equal to 0.035 wt.% of S, less than or equal to 0.25 wt.% of Cr, less than or equal to 0.25 wt.% of Ni and the balance of Fe and inevitable impurities. The 65Mnhot rolled steel plate produced in the method has the characteristics of uniform structure property, high thermal stability and high strength, and the quality of the 65Mn hot-rolled steel plate is obviously improved.

The invention discloses a cooling after rolling method for high-weather fastness hot-rolled H-steel with yield strength up to 550MPa. The high-weather fastness hot-rolled H-steel with the yield strength up to 550MPa comprises the following components in weight percentage: 0.06-0.12 percent of C, 0.30-0.60 percent of Si, 1.25-1.50 percent of Mn, 0.010-0.030 percent of P, 0.001-0.015 percent of S, 0.20-0.35 percent of Cu, 0.20-0.40 percent of Cr, 0.15-0.30 percent of Ni, 0.10-0.12 percent of V, 0.008-0.014 percent of N, 0.003-0.030 percent of Als and the balance of ferrum and residual trace impurities. An H-steel rolling process comprises the following steps of: heating a casting blank in a heating furnace, rolling by a roughing mill, rolling by a universal rolling mill, and performing two-stage rapid cooling after rolling is ended. According to the cooling after rolling method for the high-weather fastness hot-rolled H-steel with the yield strength up to 550MPa, through adopting a two-stage rapid cooling method after hot rolling is performed on the H-steel and by utilizing a refined crystalline strengthening mechanism, a precipitation strengthening mechanism and a phase change strengthening mechanism, an H-steel texture which is provided with single-phase bainite on the surface layer, is of a multiphase structure inside and has fine grains is obtained, thereby, the additive amount of alloying elements is reduced, the production cost is obviously reduced, the welding performance of the steel is improved, and the production efficiency is increased.

The invention discloses a cooling-after-rolling method of high-weather resistance hot-rolling H-shaped steel with yield strength of 500MPa. The high-weather resistance hot-rolling H-shaped steel with yield strength of 500MPa comprises the following components in percentage by mass: 0.06-0.12% of C, 0.30-0.60% of Si, 0.80-1.20% of Mn, 0.010-0.030% of P, 0.001-0.015% of S, 0.20-0.35% of Cu, 0.20-0.40% of Cr, 0.15-0.30% of Ni, 0.040-0.060% of Nb, 0.003-0.030% of Als, and the balance of iron and residual trace impurities. The H-shaped steel rolling technology comprises the steps of: heating with a casting blank heating furnace, rolling with a cogging mill, rolling with a universal mill and two-segment quick cooling after the rolling. In the invention, by adopting a two-segment quick cooling method after the hot rolling of the H-shaped steel and by use of a refined crystalline strengthening, precipitation strengthening and phase change strengthening mechanism, the H-shaped steel organization state with single-phase bainite on the surface layer and complex-phase organization inside and with small grains is obtained, the addition of the alloy elements is obviously reduced, the production cost is lowered, the weather resistance of the H-shaped steel is improved, the welding performance of the steel is enhanced, and the production efficiency is increased.

The invention discloses a super duplex stainless steel S32750 medium plate rolling process which includes blank selection, heating, high-pressure water descaling, two-roll rough rolling, and four-roll finish rolling. By increasing heating temperature, reducing rolling pass, and increasing finish rolling temperature of steel plates, edge cracks and partial cracks on the surface of the steel plates are reduced, medium plate rejection rate is lowered, rolling yield is increased, and contract fulfillment rate is increased.

The invention discloses a large section H shaped steel, which comprises the following chemical components by mass: 0.16-0.20% of C, 0.25-0.40% of Si, 1.35-1.50% of Mn, less than or equal to 0.03% of P, less than or equal to 0.020% of S, less than or equal to 0.012% of N, 0.10-0.20% of V, greater than or equal to 0.015% and less than or equal to 0.030% of Al, and the balance Fe and impurities. The invention also discloses a production method for the large section H shaped steel. The method consists of: converter smelting, LF refining, beam blank continuous casting, casting blank surface cleaning, H shaped steel rolling and straightening. By means of reasonable component design, and under the circumstance of only adding the microalloy element V, comprehensive properties of the large section H shaped steel can be improved, and the production process is simple and is in favor of popularization.