SU710766A1

SU710766A1 - Steel casting method

Info

Publication number: SU710766A1
Application number: SU782616208A
Authority: SU
Inventors: Владимир Николаевич Фролов; Виктор Александрович Кулаков; Вадим Петрович Игнатьев; Владимир Федорович Синдеев; Людмила Никитична Трилевская
Original assignee: Коммунарский горно-металлургический институт
Priority date: 1978-05-15
Filing date: 1978-05-15
Publication date: 1980-01-25

Description

Изобретение относится к металлургии, а именно к разливке стали сверху в изложницы.The invention relates to metallurgy, namely to casting steel from above into molds.

Известен способ зашиты слитков от окисления, включающий разливку сталр через слой предварительно запитого в изложницу жидкого шлака, состоящий в том, что внутреннюю поверхность изложницы перед разливкой покрывают углеродсодержашей смазкой, имеющей малую адгезию к расплавленному шлаку [1] .A known method is the protection of ingots from oxidation, which includes casting steel through a layer of liquid slag pre-washed into the mold, consisting in the fact that the inner surface of the mold is coated with a carbon-containing lubricant having low adhesion to molten slag before casting [1].

Недостаток известного способа - загрязнение стали неметаллическими включениями при прохождении через слой жидкого шлака.The disadvantage of this method is the pollution of steel by non-metallic inclusions when passing through a layer of liquid slag.

Наиболее близким к предлагаемому является способ 'защиты от окисления слитков реакционноспособных металлов с температурой плавления выше 700 С путем введения перед началом разливки в изложницу углеводородного материала, который размешают в верхней части изложницы на пористой теплоизолирующей под2 ложке толщиной, обеспечивающей в зависимости от температуры литья разложение углеводорода к : моменту начала затвердевания поверхности слитка (2) .Closest to the proposed one is a method of protection from oxidation of ingots of reactive metals with a melting point above 700 C by introducing a hydrocarbon material into the mold before starting casting, which is placed in the upper part of the mold on a porous heat-insulating substrate with a thickness that ensures decomposition of the hydrocarbon depending on the casting temperature to: the moment of the beginning of the solidification of the surface of the ingot (2).

Недостатком известного способа является то, что при размещении углеводородного материала в верхней части изложницы невозможно производить разливку металла сверху из-за расположения теплоизолирующей подложки в верхней части изложницы. При размещении подложки в нижней части изложницы асбестовая крошка будет всплывать, загрязняя' при этом металл, а при соударении струи с графитовым или чугунным диском образуются брызги, в результате чего на поверхности слитка появляются плены.The disadvantage of this method is that when placing hydrocarbon material in the upper part of the mold it is impossible to cast metal from above due to the location of the insulating substrate in the upper part of the mold. When the substrate is placed in the lower part of the mold, asbestos chips will float, contaminating the metal, and when a jet hits a graphite or cast-iron disk, splashes will form, as a result of which foams appear on the surface of the ingot.

Цель изобретения - зашита слитков от окисления и уменьшение пленообразования на поверхности слитков.The purpose of the invention is the protection of ingots from oxidation and the reduction of foaming on the surface of the ingots.

Поставленная цель достигается тем, что в качестве углеводородного материала используют гранулированный полистирол в количестве 0,5-2 г на тонну стали.This goal is achieved in that as a hydrocarbon material using granular polystyrene in an amount of 0.5-2 g per ton of steel.

При введении такого количества полистирола создаются наилучшие условия для формирования поверхности слитка и предотвращается пленообразование. Ввод в изложницу перед разливкой менее 0,5 кг гранулированного полистирола на тонну сТали приводит к образованию плен на поверхности слитка, а увеличение более 2 кг экономически нецелесообразно.With the introduction of such an amount of polystyrene, the best conditions are created for the formation of the surface of the ingot and foaming is prevented. Entering into the mold before casting less than 0.5 kg of granular polystyrene per ton of cStal leads to the formation of captures on the surface of the ingot, and an increase of more than 2 kg is not economically feasible.

Способ осуществляется следующим образом.The method is as follows.

Перед разливкой стали в изложницу на дно ее засыпают 0,5-2 кг/г гранулированного полистирола и начинают разливку металла сверху. В процессе взаимодействия струи металла происходит пиролитическое разложение углеводородов, в результате чего уменьшается кинетическая энергия струи жидкого металла, что приводит к уменьшению количества брызг и снижению количества приваров к поддону изложницы. Образующийся в процессе взаимэдействия металла с гранулированным полистиролом сажистый углерод покрывает внутреннюю часть изложницы, способствуяBefore casting steel, 0.5-2 kg / g of granular polystyrene is poured into the mold on the bottom of the mold and the casting of metal from above begins. During the interaction of the metal jet, pyrolytic decomposition of hydrocarbons occurs, as a result of which the kinetic energy of the liquid metal jet decreases, which leads to a decrease in the number of sprays and a decrease in the number of welds to the mold tray. Carbon black formed during the interaction of the metal with granular polystyrene covers the interior of the mold, contributing to

8,2 гн. Перед разливкой на дно изложницы насыпают 10 кг гранулированного полистирола. Скорость разливки составляет 2-2,5 м/мин. После стрипперования и 5 осмотра поверхности слитка плен не обнаружено. Объем зачистки в прокатных цехах сокращается на 20%.8.2 nest Before casting, 10 kg of granular polystyrene are poured onto the mold bottom. The casting speed is 2-2.5 m / min. After stripping and 5 inspection of the surface of the ingot, no captivity was found. The volume of stripping in rolling shops is reduced by 20%.

Предлагаемый спос об позволяет уменьшить пленообразование на поверхностиThe proposed method for reducing surface foaming

Ю слитков, снизить брак на первом переделе на 20% от общего количества и исключить приваривание слитков к поддону.Yu ingots, reduce rejects in the first redistribution by 20% of the total number and exclude welding of ingots to the pallet.

Claims

The invention of ognosigs for metallurgy, namely for casting steel from above into molds. A method for protecting ingots from oxidation is known, including casting steel; through a layer of liquid slag previously poured into the mold, consisting in that the internal surface of the mold is coated with a carbon-containing lubricant with low adhesion to the molten slag fl. The disadvantage of this method is that the contamination has become non-metallic inclusions when passing through a layer of liquid slag. Closest to the proposed method is to protect against oxidation of ingots of reactive metals with a melting point above 70 ° C by introducing into the mold a hydrocarbon material before the start, which is stirred in the upper T part of the mold on a porous insulating substrate with a thickness that provides decomposition hydrocarbon to: the beginning of the solidification of the surface of the ingot 12. The disadvantage of this method is that when placing the hydrocarbon material in the upper part of the mold it is impossible to cast the metal on top due to the location of the heat insulating substrate in the upper part of the mold. When placing the substrate in the lower part of the mold, the asbestos chips will float, contaminating the metal, and when the jet collides with a graphite or cast-iron disc, spatter occurs, resulting in captivity on the surface of the ingot. The purpose of the invention is to protect the ingots from oxidation and to reduce the charge absorption on the surface of the ingots. The goal is achieved by using granulated polystyrene in the amount of O, 5-2 g per ton of steel as the hydrocarbon material. With the introduction of such an amount of polystyrene, the best conditions are created for the formation of the ingot surface and the foaming is prevented. Entering into the mold before casting less than 0.5 kg of granulated polystyrene per ton of steel leads to the formation of a captivity on the surface of the ingot, and an increase of more than 2 kg is not economically feasible. The method is carried out as follows. Before pouring the steel into the mold, 0.5–2 kg / ton of granulated polystyrene are poured at the bottom of the mold, and the metal is poured from above. In the process of interaction of the metal jet, the pyrolytic decomposition of hydrocarbons occurs, resulting in a decrease in the kinetic energy of the jet of liquid metal, which leads to a decrease in the number of splashes and a decrease in the number of welds to the base plate. The black carbon formed in the process of metal interaction with granulated polystyrene covers the inner part of the mold, contributes to the improvement of the ingot surface quality, and the gaseous pyrolysis products that are formed prevent the oxidation of the liquid metal droplets from the impact of the jet with the pallet. Example. Casting steel Zps produced on top of the molds weighing 7 6 8.2 tons. Before pouring, 10 kg of granulated polystyrene is poured to the bottom of the mold. The casting speed is 2-2.5 m / min. After stripping and inspecting the surface of the ingot, no film was detected. The amount of stripping in rolling mills is reduced by 20%. The proposed method allows to reduce film formation on the ingot surface, to reduce the scrap at the first conversion by 20% of the total amount and to exclude welding of the ingots to the pallet. The invention The method of casting steel, which includes the introduction of a hydrocarbon material into the mold before casting, characterized in that, in order to protect ingots from oxidation and reduce film formation on the surface, granulated polystyrene in the amount of 0.5-2.0 kg is used as the hydrocarbon material. per ton of steel. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 426746, cl. B 22: D 7 / GS, 1971.

2. USSR author's certificate No. 50О888, cl. B 22 P 27 / GS, 1973.