CZ337497A3 - Apparatus for making chemical heating - Google Patents

Abstract

In the present invention there is disclosed an apparatus for carrying out chemical heating of molten steel in a ladle (1) being provided with bottom inlet of argon (14) and consisting from both a working platform (2) below which a ceramic cylindrical screen is suspended on a lifting device (10) and a filled section feeder (11), whereby in said ceramic cylindrical screen (5) one supersonic water-cooled nozzle (4)with four holes a with blowing height range of 200 to 300 m and cooling water pressure ranging from 1.0 to 1.2 MPa is led out from above through an access hole (3) in the ladle (1). At the same time the ceramic cylindrical screen (5) bottom edge is situated very close to the molten metal level.

Description

(57)

Apparatus for carrying out chemical heating of molten steel in a ladle (1), provided with a lower argon inlet (14), comprising, on the one hand, a working platform (2) below which a ceramic cylindrical orifice (5) is suspended on the lifting device (10); a four-hole super-sonic water-cooled nozzle (4) with a blowing height of 200 to 300 mm and a cooling water of approx. pressure of 1.0 to 1.2 MPa. The ceramic diaphragm (5) is lowered just above the surface of the melt (17) by its lower edge.

• · · φ ·· '·· * ·· ·· φφφ ΦΦ ·· · · φ

Equipment for chemical heating

Technical field

The invention relates to a device for heating molten steel in a ladle of processes.

for performing chemical during metallurgical processes

BACKGROUND OF THE INVENTION

In the production of steel, in particular for further refining of molten steel in a ladle during its off-furnace processing, it is usually necessary to heat the steel to the required temperature. One way of carrying out this heating is by so-called chemical or reaction heating, which is achieved by an exothermic reaction caused by the oxidation of aluminum or silicon added to the melt with oxygen gas supplied by a nozzle above its level. At the same time, argon is injected into the melt, alternatively or simultaneously, for the purpose of mixing the steel, alternately or simultaneously, as the upper blowing block located in the bottom of the argon blowing port usually serves only

nozzle as well as lower pans, the bottom for auxiliary mixing.

The argon supplied from above for the main mixing also serves to disperse the slag on the surface of the molten steel in the ladle and to form the so-called reaction eye.

Basically, two basic chemical heating systems, known as the Injection Refining - Up Temperature (IR-UT) process and the CAS-OB (Scaled Argon Bubbling with Oxygen Blowing) process, are performed. Methods and apparatus for carrying out such chemical heating systems are known, for example, from JP 62203259, US 4761178 or PCT application WO 89/01984. A common feature of all these devices is that they use a plurality of submersible nozzles to inject argon or oxygen and require the use of a special wire reinforced protective tube, usually referred to as a snorkel, also partially immersed in the melt to maintain the reaction eye. The immersion depth of the snorkel is 10 to 20 cm, while the argon nozzle is immersed inside the snorkel to the bottom of the pan during the entire heating process. The disadvantage of these yet

In the known devices, the submerged parts of both the nozzles and the snorkel wear very rapidly, for example, the loss of the ceramic oxygen injection nozzle is up to 1 cm per heating. Of course, this necessitates frequent replacement of these components with additional negative consequences for increased operating costs, maintenance costs, and frequent downtime.

SUMMARY OF THE INVENTION

The aforementioned disadvantage of the prior art is largely eliminated by the apparatus for carrying out chemical heating of molten steel in a ladle, provided with a lower argon feed, consisting of a working platform below which a ceramic cylindrical diaphragm is mounted on the lifting device and , according to the invention, characterized in that only one four-hole supersonic water at a pressure of 1.0 to 1.2 MPa is cooled into the ceramic cylindrical orifice from above through the access opening in the working platform at a pressure of 1.0 to 1.2 MPa. up to 300 mm, the ceramic cylindrical diaphragm being lowered just above the melt surface with its lower edge.

The invention furthermore consists in that a dosing slide of the additives is connected to the working platform and connected by a weighing conveyor belt to the main ingredient containers. The workplace is equipped with an automatic dosing system for additives.

• ·· ·

The invention is furthermore characterized in that an exhaust duct is provided below the working platform from above the pan.

The basic advantage of the heating according to the invention for this purpose is that the device for carrying out the chemical does not contain its constructional solution in comparison with all known devices

no immersion nozzles for dipping a ceramic cylindrical orifice to maintain a clean melt level without any slag particles and together with oxygen blown from a four-hole water-cooled nozzle to form a reaction eye. Blowing argon into the bath through the bottom of the ladle is fully sufficient to mix the steel. If all the parameters required for chemical heating are met, there is no excessive wear of its basic parts. An advantage of the device according to the invention is also an optimal solution of dosing of additives into molten steel and exhausting of flue gases from the space above the ladle.

Overview of the drawings

The invention will be further elucidated by means of a drawing of a specific embodiment of the chemical heating device according to the invention, in which the whole assembly is shown schematically and in partial section.

*

Γ:

DETAILED DESCRIPTION OF THE INVENTION

The apparatus for carrying out the chemical heating according to the illustrated embodiment consists of a working platform 2, which is located above the ladle 1. Below the working platform 2, a ceramic cylindrical screen 5 with wire reinforcement is suspended on the lifting device 10. platform 2 opens above the surface of the melt 17 in the ladle 1 one four-hole • ·

a supersonic water-cooled nozzle 4 connected to an oxygen supply 12 of gaseous oxygen and a cooling supply 13 for water. The ceramic cylindrical orifice 5, with its lower edge, is positioned just above the surface of the melt 17 at a height of 100 to 150 mm. The blowing height of the water-cooled nozzle 4 is 250 mm, cooling

3. is on the profiles and weighing work products an argon platform with a pressure of 1.0 alloy platforms, belt 7 s

L 2.

the water is working and the chute by the transport platform 2 is placed from the space above on the inlet 14,

MPa. Above the access opening 2 there is placed a feeder 11 filled through the reversing belt 16 by the main additive containers 8. A suction line 9 of the ladles 1 is arranged below. The ladle 1 is below the working transfer car 15 and is provided with a blowing block in the bottom of the ladle 1.

The function of the device and the actual process of chemical heating is already similar to the known devices.

Industrial applicability

The device according to the invention is particularly applicable in the field of off-furnace steel processing.

Claims (1)

PATENT CLAIMS Apparatus for carrying out chemical heating of molten steel in a ladle, provided with a lower argon inlet, comprising a working platform below which a ceramic cylindrical orifice is suspended on a lifting device, and a feeder for filled profiles into a ladle, characterized in that (5) from above through the access opening (3) in the working platform (2), above the surface of the melt (17) is supersonic water with a nozzle (4) with a height in the ladle (1) one four-hole pressures blowing of 200 to 300 mm, the ceramic cylindrical orifice (5) being lowered just above the surface of the melt (17) with its lower edge. Apparatus according to claim 1, characterized in that an additive chute (6), connected by a weighing conveyor belt (7) to the main additive containers (8), is located above the access opening (3) in the working platform (2). Device according to claim 1 and 2, characterized in that an exhaust duct (9) from the space above the ladle (1) is arranged below the working platform (2).