RU2297458C1 - Charge to converter loading method - Google Patents

Abstract

FIELD: metallurgical processes, namely for loading scrap metal and for pouring cast iron to converter.

SUBSTANCE: method comprises steps of loading scrap metal to converter and pouring cast iron from ladle suspended in ropes of cargo hoisting crane. Just before pouring cast iron to converter, along surface of each rope water or ethylene glycol streams are fed with flow rate 0.1 - 0.5 l/min for each rope. After pouring of cast iron feed of water or ethylene glycol is interrupted.

EFFECT: improved safety and reliability for loading charge to converter.

1 ex

Description

The invention relates to metallurgy, and more particularly, to processes for filling scrap and pouring iron into a converter before blowing the melt with oxygen.

The closest in technical essence is the method of filling the charge into the converter, including loading scoops of scrap into the converter and pouring molten iron into it from the ladle suspended on the ropes of a hoisting crane. To protect the environment from harmful emissions from the converter and the ropes of the crane before pouring cast iron into the working space of the converter for 0.2-2.0 minutes a neutral gas with a flow rate of 0.5-1.0 m ³ / t of melt is fed into converter. Neutral gas is fed into the converter through its neck, bottom tuyeres or through its steel outlet (see RF patent No. 2116352, class C 21 C 5/28, BI No. 21, 1998).

The disadvantage of this method is the low resistance of the ropes of the crane, on which the bucket is suspended. This is due to the fact that during the casting of pig iron into the converter, the latter emits highly heated gases, which leads to overheating of the ropes. During periodically repeating processes of casting cast iron into the converter, the ropes fail due to overheating from heat generation from the converter. The neutral gas supplied to the converter can reduce the harmful effects on the ecology and the environment of harmful toxic gases and substances released from the converter when cast iron is poured. However, the known method does not protect the ropes from overheating.

The technical effect when using the invention is to ensure the reliability and safety of filling the charge into the converter by increasing the resistance of the ropes of hoisting cranes.

The specified technical effect is achieved by the fact that the method of filling the charge into the converter involves loading scoops of scrap into the converter and pouring liquid cast iron into it from the ladle suspended on the ropes of a hoisting crane.

Immediately before the casting process, cast iron is fed into the converter along each rope along the surface with water or ethylene glycol with a flow rate of 0.5-0.1 l / min; after casting, the flow of water or ethylene glycol is stopped.

The increase in the resistance of the ropes of the crane will occur due to forced liquid cooling of the ropes along their length during the pouring of molten iron into the converter under conditions of maximum heat release from it. The range of coolant flow rates in the range 0.1-0.5 l / min is explained by the thermophysical laws of heating the ropes on which the ladle with molten iron is suspended. At lower values, the ropes will overheat and fail. At high values, the coolant will be overspended, and it may get into the converter.

The specified range is set depending on the capacity of the converter and the length of the ropes from the drum of the crane to lifting hooks.

The analysis of scientific, technical and patent literature shows the lack of coincidence of the distinguishing features of the method with the signs of known technical solutions. Based on this, it is concluded that the claimed technical solution meets the criterion of "inventive step".

The following is an embodiment of the invention that does not exclude other variations within the scope of the claims.

The method of filling the charge into the Converter is as follows.

Example.

Before smelting steel grade 3 into a tilted converter with a capacity of 150-350 tons of melt, metal scrap is loaded through its throat using scoops suspended on metal ropes of a hoisting crane. Scrap is loaded using 1-4 scoops. The total scrap consumption is set within 20-30% of the melt capacity in the converter. After filling the scrap, cast iron is poured into the neck of the converter from a ladle suspended on the ropes of a hoisting crane. The diameter of the ropes is 30-40 mm. The distance or length of the ropes from the drum of the crane to the lifting hooks is 2-8 m. The number of ropes is 4-8.

Immediately before the process of casting iron, jets of water or ethylene glycol with a flow rate of 0.1-0.5 l / min are fed along the surface of each wire along the rope to the converter.

To supply fluid to the ropes, special metering devices are used located on the metal structures of the crane. The indicated devices are triggered automatically or are turned on or off manually by the crane operator from the crane control panel.

After casting iron, the flow of water or ethylene glycol to the surface of the ropes is stopped, the bucket is removed from the converter and the latter is installed in a vertical position, a lance is introduced into the neck of the converter and the melt is purged with oxygen.

The application of the invention allows to eliminate the overheating of the ropes of hoisting cranes, which leads to an increase in their resistance by 2–3 times.

Claims (1)

A method of filling a charge into a converter, including loading scrap into the converter and pouring molten iron into it from a ladle suspended on the ropes of a crane, characterized in that immediately before pouring cast iron into the converter along the rope, water or ethylene glycol is supplied at a flow rate of 0, 1-0.5 l / min for each rope, after pouring cast iron, the flow of water or ethylene glycol is stopped.