3results about How to "Avoid Nitrogen Problems" patented technology

This invention relates to a steel for automobile engine pistons and its manufacturing method. The chemical composition of the steel, by weight percentage, is: C: 0.41–0.47%, Si: 0.15–0.35%, Mn: 0.70–1.00%, Cr: 1.10–1.40%, P: ≤0.020%, S: 0.015–0.035%, Mo: 0.17–0.27%, Al: 0.010–0.030%, N: 0.0040–0.0060%, with the balance being Fe and unavoidable impurities. The microstructure consists of ferrite and pearlite, with uniform distribution of ferrite and pearlite structures. The geometric center distance between each ferrite and pearlite structure is 15–30 μm. The hot-rolled hardness of the steel is ≤230 HBW, and the banded structure in the steel is ≤1.5 grade. The product features a narrow range of carbon deviation in cross-section, shallow decarburized layer and microcrack depth on the steel surface, low hot-rolled hardness, good banded structure, and high tensile strength after quenching and tempering.

The utility model discloses an integral casing pipe structure for pouring, which comprises a casing pipe main body, a pouring hole I and a pouring hole II are arranged in the casing pipe main body to form a double-hole casing pipe structure, the pouring mode during pouring is double-hole intrusive water gap pouring, and both the pouring hole I and the pouring hole II are through holes. By using the integral sleeve, nitrogen and oxygen increase of molten steel from a tundish to a crystallizer can be effectively avoided, secondary oxidation of the molten steel is reduced, and the quality of high-quality special steel products is improved. According to the technical scheme, the whole pipe is used for casting, particularly the double-hole sleeve is used for casting, so that the flowing state of molten steel injection flow can be effectively adjusted, the product quality is improved, and the casting stability can be kept in the unstable casting process.

The invention discloses a nitrogen removal agent for low-nitrogen metal manganese ingot production and a preparation method thereof, relates to the technical field of metal material processing, and aims to solve the problems that in the current low-nitrogen metal manganese ingot processing process, the nitrogen content in a metal manganese ingot is increased, and the nitrogen removal effect is poor due to the fact that the low-nitrogen metal manganese ingot and nitrogen in the environment are easily subjected to a combination reaction. The silicon nitride slag remover comprises a reducing agent and a slag remover, the reducing agent reacts with nitrogen in air to generate a new nitride when the liquid manganese water is heated to 1300 DEG C or above, and the slag remover can adsorb silicon nitride on the surface of the manganese water and form a protective film on the surface of the manganese water. According to the nitrogen removal agent and the production process thereof, the nitrogen content in the metal manganese ingot can be remarkably reduced, a dual-action mechanism is adopted, it is ensured that the nitrogen content of the metal manganese ingot is effectively controlled in the whole production process, and therefore the quality of the metal manganese ingot is improved; therefore, the requirements on low-nitrogen metal manganese ingots in the industries of steel, nonferrous metals and the like can be better met.