Abstract: The present disclosure relates to the technical field of rails welding, and particularly to a method for optimizing microstructure of a rail welded joint, the method comprises the following steps: step 1): subjecting a rail web area of a to-be-cooled welded joint which is obtained by flash butt welding to an accelerated cooling by means of an accelerated cooling device and by using compressed air as a cooling medium, measuring and monitoring temperature of a central position of the rail web of the welded joint while cooling; step 2): stopping the accelerated cooling when the temperature of the central position of the rail web drops to a preset temperature, then placing the welded joint in air and naturally cooling to room temperature, wherein the rail is a pearlite rail having a carbon content of 0.6-0.9 wt %.

Abstract: The invention relates to a turnout rail production technology, in particular to a deeply-hardened-surface turnout rail with high degree of undercooling and the preparation method thereof. The invention aims to solve the technical problem by providing a deeply-hardened-surface turnout rail with high degree of undercooling featured in even hardness distribution and a deeply hardened surface layer and the preparation method thereof. The method is described as follows: feeding molten iron for converter smelting?furnace rear argon blowing station?LF refining?RH vacuumization?casting steel blanks?slow cooling in the slow cooling pit?austenitic homogenization?rail rolling?heat treatment; in the converter smelting process, adding 0.2-0.3% Cr, 0.04-0.06 V and 0.75-0.80% C; the heat treatment process is divided into two cooling stages.

Abstract: The invention discloses a continuous hot rolled coil for a high collapse-resistant SEW petroleum casing and a manufacturing method thereof, and belongs to the technical field of hot continuous rolling production. Provided is a continuous hot rolled coil for a high collapse-resistant SEW petroleum casing with low alloy element cost and excellent initial welding property, and a manufacturing method thereof. The production cost of the hot continuous rolled coil is lowered by reducing expensive alloy elements such as Mo and V therein, and strictly controlling the content components of chemical elements such as Cr, Mn and Ti.

Abstract: The present disclosure relates to the technical field of rails welding, and particularly to a method for optimizing microstructure of a rail welded joint, the method comprises the following steps: step 1): subjecting a rail web area of a to-be-cooled welded joint which is obtained by flash butt welding to an accelerated cooling by means of an accelerated cooling device and by using compressed air as a cooling medium, measuring and monitoring temperature of a central position of the rail web of the welded joint while cooling; step 2): stopping the accelerated cooling when the temperature of the central position of the rail web drops to a preset temperature, then placing the welded joint in air and naturally cooling to room temperature, wherein the rail is a pearlite rail having a carbon content of 0.6-0.9 wt %.

Abstract: The present disclosure relates to the manufacturing of railway steel rail, and a post-weld heat treatment method for 1,300 MPa-level low-alloy heat-treated steel rail. The method comprises: (1) subjecting a steel rail welded joint having a residual temperature of 900-1,100° C. to a first stage cooling to lower the welded joint surface temperature to 650-720° C.; (2) subjecting the steel rail welded joint to a second stage cooling to lower the welded joint surface temperature to 480-550° C.; (3) subjecting the steel rail welded joint to a third stage cooling to lower the welded joint surface temperature to 10-30° C. The heat treatment takes advantage of the welding waste heat and does not require a reheating. The martensitic structure in the metallographic structure of the steel rail welded joint can be controlled to ?1% and the fatigue life can reach 3 million times, which is conducive to operation safety of the railway.

Abstract: The invention relates to the field of railway, and discloses a hypereutectoid rail and a manufacturing method thereof, which includes rolling a steel billet containing V and Ti, wherein, based on its total weight, the steel billet contains C of 0.85-0.94 wt %, and the relation between the start rolling temperature Tstart/final rolling temperature Tfinal and the content of V and the content of Ti satisfies the following formulas: Tstart=1100+a([V]+5[Ti]), Tfinal=750+b([V]+5[Ti]), wherein, 500?a?800, 300?b?500; based on its total weight, the steel billet contains V of 0.03-0.08 wt %, Ti of 0.011-0.02 wt %, and [V]+5[Ti]: 0.12-0.14 wt %. The hypereutectoid rail manufactured with the method has excellent comprehensive performance of strength and toughness.

Abstract: The present invention relates to a heat treatment method for increasing the depth of hardening layer in a steel rail, and belongs to the field of steel rail production process. The technical problem to be solved in the present invention is to provide a heat treatment method for increasing the depth of hardening layer in a steel rail and a steel rail obtained with the method. The method comprises the following steps: cooling a finished rolling steel rail by natural cooling, till the temperature at the center of rail head surface is 660˜730° C.; cooling the steel rail by accelerated cooling at 1.5˜3.5° C./s cooling rate, till the temperature at the center of rail head surface is 500˜550° C.; increasing the cooling rate by 1.0˜2.0° C./s and further cooling down the steel rail, till the temperature at the center of rail head surface is 450° C. or lower; then, stopping the accelerated cooling, and cooling down the steel rail by air cooling to room temperature.

Abstract: The present invention discloses a method for preparing hypereutectoid steel rail in which the composition of the billets adopted is: C: 0.86-1.05 wt. %; Si: 0.3-1 wt. %; Mn: 0.5-1.3 wt. %; Cr: 0.15-0.35 wt. %; Cu: 0.3-0.5 wt. %; P: 0.02-0.04 wt. %; S: ?0.02 wt. %; Ni: ½-? of the content of Cu; at least one of V, Nb and Re; Fe and unavoidable impurities of the rest. The present invention further provides a hypereutectoid steel rail prepared by the foregoing method. By the hypereutectoid steel rail preparation method provided by the present invention, the high-carbon billets with a specific composition provided by the present invention can be made into hypereutectoid steel rails with good corrosion resistance and tensile properties.

Abstract: A method of producing titanium metal with titanium-containing material which includes mixing, pressing and drying the titanium-containing material with a carbonaceous reducing agent to obtain a resultant as a first anode. Using a metal or an alloy as a first cathode, and using an alkali metal chloride molten salt and/or an alkaline earth metal chloride molten salt as a first electrolyte to constitute a first electrolysis system, to perform pre-electrolysis in an inert atmosphere to obtain a residual anode. After the residual anode is washed, molded and dried, using the residual anode as a second anode, using a metal or an alloy as a second cathode, using an alkali metal chloride molten salt and/or an alkaline earth metal chloride molten salt as a second electrolyte to constitute a second electrolysis system, to perform electrolysis in an inert atmosphere to obtain titanium metal powder.

Abstract: The present invention discloses a method for heat treatment of hypereutectoid steel rail, including the following steps: holding the temperature of the steel rail of which temperature is above 900° C. after finish rolling, conducting a first cooling stage for the steel rail at the first cooling speed after the temperature holding to reduce the temperature of railhead surface layer of the steel rail to 700-750° C., conducting a second cooling stage for the steel rail at the second cooling speed to reduce the temperature of railhead surface layer of the steel rail to 550° C., conducting a third cooling stage for the steel rail at the third cooling speed to reduce the temperature of railhead surface layer of the steel rail to 450° C. or less, and continuing to cool the steel rail in the air.

Abstract: The present invention provides a heat treatment method of turnout track comprising performing an accelerated cooling on the turnout track to be treated having a railhead tread with a temperature of 650-900° C. so as to obtain the turnout track with full pearlite metallographic structure, wherein the accelerated cooling velocity performed on the working side of railhead of the turnout track is higher than that performed on the non-working side of the railhead of the turnout track. The present invention provides a turnout track obtained with a heat treatment process as depicted therein. The turnout track in present invention has good straightness; both the hardness and tensile strength of the working side of railhead are higher than that of the non-working side of railhead.

Abstract: The present disclosure discloses a heat treatment method for a bainitic turnout rail, which includes: naturally cooling the turnout rail at a temperature in an austenite region after being finishing rolled to 450-480° C. at a tread center of a rail head of the turnout rail; accelerated cooling the naturally cooled turnout rail to 230-270° C. at the tread center of the rail head, a cooling rate at the tread center and a non-working side of the rail head being 1.5-5.0° C./s, a cooling rate at the working side of the rail head increasing by 0.1-1.0° C./s based on 1.5-5.0° C./s; continuously accelerated cooling the working side, the tread center and the non-working side of the rail head at a cooling rate of 0.05-0.25° C./s to decrease a temperature of the tread center of the rail head to 265-270° C.; and finally, naturally cooling the turnout rail to an ambient temperature.

Abstract: The invention relates to a high-impact-toughness steel rail and a production method thereof, and belongs to the field of steel rail material production. The present invention is to provide a high-impact-toughness steel rail. The high-impact-toughness steel rail provided in the present invention is a pearlite steel rail with 0.05˜0.09 ?m of inter-lamellar spacing and 30˜35 J of ballistic work at normal temperature; the chemical components of the steel rail in weight percentage are: C: 0.71-0.82 wt %, Si: 0.25-0.45 wt %, Mn: 0.75-1.05 wt %, V: 0.03-0.15 wt %, P: ?0.030 wt %, S: ?0.035 wt %, Al: ?0.020 wt %, and Fe and inevitable impurities of the remaining content. The U-type impact toughness of rail head of the steel rail manufactured with the method disclosed in the present invention can be 30 J or more, and the tensile strength is about 1,300 MPa or higher.

Abstract: The present invention relates to a high-strength, highly wear-resistant, and highly contact-fatigue-resistant steel rail and a production method thereof, and belongs to the field of black steel manufacturing technology. The present invention provides a high-strength and highly fatigue-resistant steel rail, comprising the following chemical components by weight percentage: C: 0.76%˜0.86%; Si: 0.6%˜1%; Mn: 0.7%˜1.5%, Cr: 0.1%˜0.5%, and 0.8%?Mn %+Cr %?1.6%; V: 0.05%˜0.3%, Ni: 0.1%˜0.35%, and 0.15%?V %+Ni %?0.4%; Mo: ?0.03%; P: ?0.02%; S: ?0.015%; Fe and inevitable impurities: the remaining content, wherein, the metallurgical structure of the steel rail is fine pearlite+A, where, A is proeutectoid ferrite or proeutectoid cementite, and A?2%. The tensile strength of the obtained steel rail is 1,260 MPa˜1,420 MPa.

Abstract: A method for detecting paths and amount of loss of desulfurization organic components in a flue gas desulfurization system includes preparing a to-be-measured solution and a base standard solution, and diluting the base standard solution with water to a plurality of standard solutions containing different concentrations of desulfurization organic components; adjusting the to-be-measured solution and standard solutions to have a strong acidity, respectively, such that each of desulfurization organic components in the to-be-measured solution and standard solutions exists in ion forms; heating and oscillating the to-be-measured solution and standard solutions, respectively; respectively detecting carbon elements in the standard solutions, to form a linear relationship between concentrations of the desulfurization organic components in the standard solutions and detected carbon element data; and detecting carbon elements in the to-be-measured solution, and obtaining a total concentration of the desulfurization or

Abstract: A pearlitic steel rail with high strength and toughness and a producing method thereof. The producing method comprises: controlling the following processing conditions in a rolling procedure to produce the pearlitic steel rail with high strength and toughness: initial rolling temperature of 1,120-1,180° C., final rolling temperature of 840-880° C., rail profile reduction in last two rolling passes of 6%-12%; the steel rail is cooled to 600° C. or lower at a cooling rate ?2.0° C./s after final rolling, and then air-cooled to room temperature; the chemical composition of the steel rail meets the following requirements: C: 0.75%-0.84%, Si: 0.30%-0.80%, Mn: 0.50%-1.50%, V: 0.04%-0.12%, Ti: 0.004%-0.02%, and 0.10%?V+10Ti?0.25%, [N]?30 ppm, P?0.020%, S?0.008%, with the remaining content consisting of Fe and inevitable impurities.

Abstract: The present invention relates to a heat treatment method for increasing the depth of hardening layer in a steel rail, and belongs to the field of steel rail production process. The technical problem to be solved in the present invention is to provide a heat treatment method for increasing the depth of hardening layer in a steel rail and a steel rail obtained with the method. The method comprises the following steps: cooling a finished rolling steel rail by natural cooling, till the temperature at the center of rail head surface is 660˜730° C.; cooling the steel rail by accelerated cooling at 1.5˜3.5° C./s cooling rate, till the temperature at the center of rail head surface is 500˜550° C.; increasing the cooling rate by 1.0˜2.0° C./s and further cooling down the steel rail, till the temperature at the center of rail head surface is 450° C. or lower; then, stopping the accelerated cooling, and cooling down the steel rail by air cooling to room temperature.

Abstract: The present invention discloses a bainitic steel rail containing trace amounts of carbides, wherein, the bainitic steel rail mainly consists of bainitic structures, the carbides have a length of 0.05-0.5 ?m, the major axis of carbides is oriented to a direction at a 50-70° included angle from the direction of the major axis of bainitic ferrite plates, and the carbides account for 1%-5% by volume. The present invention further discloses a method for producing a bainitic steel rail containing trace amounts of carbides, comprising: cooling a steel rail with residual heat after finish rolling by air cooling, till the temperature at the center of the rail head tread reaches 420-450° C.; cooling the rail head part of the steel rail by accelerated cooling at a 2.0-5.0° C./s cooling rate, till the temperature at the center of the rail head tread reaches 220-240° C.; loading the steel rail into a tempering furnace and tempering at 300-350° C.

Abstract: A metal protective coating is provided, which is obtained by mixing homogeneously a raw mixture, which contains water soluble silicate, promoter, silane coupling agent, silicon oxide packing, water soluble film formation resin, and water; wherein, the promoter is at least one selected from the group consisting of methyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, carboxymethyl-hydroxyethyl cellulose, and their soluble salts; the silane coupling agent contains a first silane derivative shown in formula (1), wherein, R1, R2, and R3 are methoxyl or ethyoxyl respectively, and n is an integer with the range of 1-4. A hot-dip Zn metallic material and a hot-dip Al—Zn alloy metallic material are further provided. The protective film formed by the metal protective coating as provided has outstanding corrosion resistance, water resistance, thermal resistance, and fingerprint resistance properties.

Abstract: A method of manufacturing direct reduction iron and a reduction firing apparatus. The apparatus has a reduction furnace including a left chamber, a right chamber, a material containing device, a step mechanism, a slag distributing device, a charging device, heating burners, a fume extraction path, a charging device, a material receiving tank and a slag discharging path. The method includes the following steps: distributing and charging the slag in the material containing device; carrying and sending the material containing device through a preheating station, a heating station and a reduction station sequentially. Meanwhile, heating the material to be reduced by a combustion of fuel with the heating burners; discharging the reduced material into the material receiving tank; placing the material device from which the material is discharged into the feeding side of the other chamber, then a next work circulation begins.