SU925527A1 - Method of chemical capping of rimmed steel ingots - Google Patents

Description

movement of the metal in the mold, and hence the height of the wave during boiling of the metal. With the introduction of the same amount of deoxidizing agent, its penetration into the metal is deeper in the case of intense boiling than in a less intense one. The height of the wave allows predicting the depth of penetration of deoxidizing agents into the metal or, on the contrary, knowing the required depth: the penetration rate can be used to determine the required amount of deoxidation from the height of the wave. To obtain a high-quality ingot, it is necessary to have deoxidizing penetration into the metal to a depth below which, although the formation of gas bubbles occurs, it is impossible for them to float upwards. Taking into account the necessary penetration depth, is determined by the height of the wave, the required amount of deoxidizing agents in the first portion of

with

formula t -. Permanent is selected for each steel grade. For example, for 10.4 tons of steel ingot 10 kp it is equal to 90, for steel Spp - 30.

In the process of solidification due to segregation, gas bubbles form on the lower horizontal ingots. Formed and grown to a certain size bubbles can float upwards. In order to avoid bubbles in the upper part, it is necessary to have an excess of freely dissolved deoxidizing agents. In the presence of the last gas bubble, falling into this zone, interacts with deoxidant. Palicia of the dissolved deoxidizers in the upper part is achieved by introducing it into the second portion, the amount of deoxidizing agents in which is determined as the difference between the total amount of deoxidizing agents injected into the ingot and the amount in the first portion.

The amount of thinner in the first batch, determined depending on the wave height, and in the second batch contributes to obtaining a dense metal layer of optimum thickness in the upper part of the ingot.

The method is carried out as follows.

The chemical clogging of 10.4 tons of ingot of steel -10 kp, containing 0.10% carbon, measures the height of the boiling wave of the metal in the mold using a level gauge. The total amount of aluminum selected for carbon content is 6.0 kg per ingot. If the wave size is 30 mm, then the amount of aluminum in

90

the first batch is t .-. 3.0 kg

ou

on the ingot. The amount of aluminum in the second portion is 6.0-3.0 3.0 kg per ingot.

The proposed method allows the introduction of deoxidizing agents into the metal, taking into account the intensity of boiling and the penetration of the deoxidizer to the desired depth. The ingots obtained by the described method have the necessary thickness “of the bridge in the upper part. During the head trim, no gas cavities are opened from the ingot rolls that are not welded during rolling. As a result, the loss of metal from the head trim from ingots is reduced.

Claims (2)

1. A method of chemical blocking of boiling steel ingots, including the introduction of a deoxidizing agent into the metal in two portions, the second portion of the deoxidizing agent being introduced 15-25 seconds after the first, characterized in that, in order to reduce the head trim of the ingot, the height of the boiling wave is measured metal and determine the amount of deoxidizing for both portions. 2. A method according to claim 1, characterized in that the amount of deoxidizing agents of the first portion is determined according to the form GP 3 t g, where c is constant for each steel grades; b - wave height. The source of information taken into account in the examination: 1. USSR author's certificate .YO 399295, cl. B 22 D 7/00, 1971.