Pangang Group Co. | Date: 2013-10-16
A method for heat-treating a bainite steel rail is disclosed. The method includes: cooling a rolled steel rail naturally to lower a surface temperature of a rail head of the steel rail to 460 C. 490 C.; cooling the steel rail forcely at a cooling rate of 2.0 C./s-4.0 C./s to lower the surface temperature of the rail head to 250 C.-290 C.; placing the steel rail in an ambient temperature until the surface temperature of the rail head is more than 300 C.; performing a tempering on the steel rail in a heating furnace at 300 C.-350 C. for 2 h-6 h; and air cooling the steel rail to the ambient temperature. Steel rails heat-treated by present method may have a stable retained austenite structure and a good mechanical performance.
Pangang Group Co. | Date: 2015-05-01
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. for 4-6 h; then, cooling the steel rail by air cooling to the room temperature. The steel rail provided in the present invention has outstanding wear resistance and contact fatigue resistance properties, and can meet higher requirement for the service of railroad steel rails, and the product is especially applicable to heavy-duty railroads.
Pangang Group Co. | Date: 2013-10-24
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.
Pangang Group Co. | Date: 2013-08-23
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.
Pangang Group Co. | Date: 2014-04-25
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 organic components in the to-be-measured solution according to the linear relationship.