SU1371972A1 - Lip-pour ladle for inoculating iron-carbon alloys - Google Patents

Abstract

The invention relates to the field of metallurgy and foundry, in particular to the after-furnace-treatment of cast iron directly in a ladle before pouring it into molds. The purpose of the invention is to reduce the pyro effect, increase the stability and efficiency of the modification process by preventing the modifier from occurring and maintaining excessive pressure under the cover and reducing chilling in castings. A kettle dipper for modifying iron-carbon alloys with magnesium-containing ligatures includes a lined housing with a sealed lid and toe and a chamber formed by a side partition at the bottom of the ligature bucket. The bucket is provided with a bunker for a secondary graphitizing modifier mounted on the lid above the toe of the bucket, the lid being detachable with a gas outlet and a rod with a flap overlapping the chamber for the ligature from above. The side bulkhead is perforated with openings. The bucket design allows for greater uptake of magnesium and significantly reduces the consumption of master alloy. 1 hp f-ly, 2 ill., 1 tab. (L

Description

The invention relates to metallurgy and foundry, in particular, to secondary treatment of cast iron by cutting directly into a ladle before pouring it into molds.

The purpose of the invention is to reduce the pyroeffect, increase stability and

the effectiveness of the process of modification

nor by preventing the floating

modifying and maintaining overpressure under the lid and reducing chill in the castings.

FIG. 1 shows the proposed teapot bucket, general view; FIG. 2 is a section A-A in FIG. one.

The bucket body 1 has a sock 2 designed to fill the bucket with liquid metal from the furnace and pour the metal into molds. The bucket body and the sock are lined with refractory material, and the sock with the bucket cavity has an associated channel 3. At the bottom of the bucket there is a chamber 4 for accommodating a magnesium-containing master alloy formed by the bucket wall and a partition 5 erected at the bottom of the bucket, which exceeds the upper level of the swing 3 by 50- 80 mm. In order to avoid the modifier in the chamber 4 when it is in contact with the first batch of metal, lowering the temperature and increasing the viscosity of the cast iron, the partition 5 has openings 6 located opposite the communicating channel 3, providing a steady flow of the hot metal chamber.

The bucket is made up of two parts, semi-bolts 7 and 8, which are pressed against the body of the bucket 1 by means of screw clamps 9. To seal before covering the lid around the perimeter of the bucket, a layer of refractory viscous mass is laid.

Polukryshka 7 has a gas outlet pipe 10, which ensures the release of gases and the maintenance of excess pressure under the cap 1.5-2.0 atm. during the modification process, which, in turn, contributes to the intensification

the process of assimilating magnesium with liquid iron. Polukryshka 8 has a rigidly fixed rod 11 reinforced with a refractory material, at the end of which there is fixed a graphite or other refractory material valve 12, designed to prevent ligature pieces from floating up on the metal mirror. Shutter 12

0 5 0

Q

with

0

five

has a shape. Corresponding to the shape of the camera 4.

For free release of magnesium vapors from chamber 4, the dimensions of the valve 12 and the length of the rod must ensure that the chamber between the wall of the bucket, the partition 5 and the valve 12 should overlap the chamber. To evenly distribute the magnes in the metal, the valve 12 also has holes, the cross-sectional area of which should provide flap strength 12.

For secondary modification in order to prevent the formation of structurally free carbide inclusions of B castings during crystallization over toe 2, a silo 13 is installed on the half-cover 7 for accommodating the graphitizing modifier.

Modifying the iron with magnesium-containing ligatures in the proposed teapot scoop ensures high stability of the modification, achieving a higher absorption of magnesium iron (55-75%), which significantly reduces the consumption of magnesium-containing ligature, the absence of luminescence and smoke in the atmosphere of the shop, which significantly improves sanitary hygienic labor conditions, secondary graphitizing modification, which allows to obtain stable without structural-free inclusions of cementite castings with a cross section of more than 5 mm mechanical properties ((R 620-752 MPa; (1.400-560 MPa; 2.0-4.0%; HB 187-229), corresponding to the marks Вг 50-2, Вг 60-2, the ability to remove slags from the metal mirror after the end of the modification process, which allows the bucket to be used repeatedly during mass production.

The bucket works as follows.

Before modifying the semi-roller 8 with the rod 11 and the valve 12 is removed, ligature, fluxing and other additives are loaded into chamber 4, then the half-lid 8 is installed on the bucket and fixed with screw clamps 9, a secondary modifier is loaded into the hopper 13 (for example, 75% ferrosilicon in the amount of 0.4-0.8 wt.% from the mass of the processed liquid metal in the ladle), then the bucket is served with a toe 2 under the chute of the furnace. The metal from the furnace along the chute enters the toe 2 and through the channel 3 into the cavity of the ladle. With

contact with metal ligature occurs during the modification process. The level of the metal in the ladle is increased, and the flap 12 holds the pieces of the ligature in chamber 4, protecting it against the metal mirror. Magnesium couples, rushing into the gaps between the valve 12, the partition 5, the wall of the case and into the holes in the valve, provide for the total volume of the meta machine.

After filling 2/3 of the volume of the metal bucket at the time of termination of the reaction of the magnesium-containing master alloy, the operator remotely from

closes the flap of the hopper 13, the secondary modifier enters the sock 2 and injects a metal stream into the bucket cavity.

After the bucket is filled with metal to the level of the cut of the sock 2, the supply of metal is stopped, the bucket is fed to the site, the semi-roller 8 is removed with the rod 11 and the valve 12, the slag is cleaned and fed to the casting area.

The number of modifiers and the mechanical properties of castings from iron, modified in the proposed ladle are presented in the table.

 The numerator is in the original cast iron, the denominator is after the modification.

As can be seen from the table, the modification in the proposed kettle teat makes it possible to obtain the stable mechanical properties of castings with a relatively low consumption (1.5–1.6 wt.% Of the treated liquid iron) magnesium-containing master alloy.

The use of the proposed ladle to modify cast iron and other iron-carbon alloys will provide smokeless modification.

by improving the sanitary and hygienic conditions of labor, higher absorption of magnesium, which will significantly reduce the consumption of ligature, the secondary modification by graphitiere modifiers, the removal of slags from the metal mirror after the end of the modification process.

Claims (2)

1. A teapot ladle for modifying iron-carbon alloys with magnesium-containing ligatures, comprising a lined case with a hermetic lid, a toe and a chamber formed by a side partition at the bottom of the ligature bucket, characterized in that, in order to reduce the pyroelectric effect, increasing the stability and zffektivnosti modifying process by preventing the floating of modifying and maintaining the overpressure under krshkoy and reduce chill in the castings, it is provided with a hopper for secondary grafitizirukmtsego modifier, reinforced on the cover over the toe of the bucket, wherein krshhka performed detachable with a gas outlet pipe and a drive rod with a flap overlapping the top chamber for the ligature. 2. Bucket pop.1, which is different from the fact that the side partition is made with holes. f {/ g. 7J