SU1235919A1 - Tuyere - Google Patents

Description

one

The invention relates to ferrous metallurgy, and more specifically to tuyeres for the purging of metal with oxygen in steelmaking aggregates of a continuous converter-type operation.

The purpose of the invention is to increase the dynamic head of the outgoing gas jet, increase the durability of the tuyere head by creating supersonic gas outflow rates and reducing the attenuation of the gas velocity along the length of the jet core.

FIG. 1 shows a lance, a vertical section in a direction perpendicular to the major axis of the nozzle; in fig. 2 shows section A-A in FIG. one; in fig. 3 - lance, vertical section in the direction of the major axis of the nozzle; in fig. 4 — node I in FIG. 3

The lance consists of three coicentrically arranged pipes 1–3, tip 4 with nozzle 5, forming paths for oxygen supply, supply and removal of cooling water.

The path of the oxygen supply is the inner pipe 1. A medium separation pipe 2 with pipe 1 and the other. The ridge 4 forms the cooling water supply path, and with the outer pipe 3 it forms the cooling water outlet path. The separator tube 2 is provided with two guide blades 6 for providing more intensive cooling of the faces of the nozzle 5.

The nozzle 5 is designed to produce a flat supersonic jet and has a confuser 7, a critical section 8 and a diffuser 9. In cross section, the nozzle represents

breeze oval eccentric in cree

This section is 1: 5-1: 7. Thus, a section by a plane perpendicular to the major axis of the oval section is similar to the Laval nozzle profile. The opening angle is a diffuser wall of 6-8 ° per side (usually used in practice). The nozzle length is determined by the jet opening parameters.

When using a tuyere to purge a metal in a SAND flow reactor, the nozzle dimensions are determined by:

, 008-0.012A,

where a is the small-axis of the critical section of the nozzle; And - the width of the reactor.

cr

/but.

five

0

5 o

five

0

.

0

five

191

where b is the major axis of the critical

nozzle sections;

F is the area of the nozzle throat, determined by the required oxygen consumption using standard techniques.

The lance works as follows. A nozzle in the form of a slit with high dynamic characteristics of gas outflow leads to the formation in the metal of the reaction zone, which is elongated along the greater axis of the bath of the steelmaking unit of continuous action.

The technological advantages of the slit-shaped supersonic nozzle allow the tuyeres to be positioned at greater distance from the bath surface than in the case of using Laval nozzles of circular cross section or rectangular nozzles with even walls. The depth of penetration of the jet into the metal does not change, and the lance works under much more favorable conditions. The temperature effect on the tuyere head is significantly reduced due to the distance of the reaction zone, a smaller amount of slag and metal splashes fall on the head. Due to this, the resistance of the tuyeres is mainly achieved. In addition, a more smooth course of purging, as well as a significant simplification of the design of the head, contributes to the durability of the tuyere.

CooTHomeiffle nozzle width to length is chosen equal to 1: 5-1: 7. This is due to the fact that with a smaller width of the nozzle the jet is too flat, not sufficiently rigid, as a result of which the depth of the reaction zone decreases, the absorption of oxygen decreases, and with a larger width of the nozzle, the advantages of the slit nozzle over the round one are not fully realized. The geometrical dimensions of the tuyeres heads with the squeaky supersonic nozzles of the specified ratio of the nozzle width to its length do not exceed the sizes of the multichannel heads (4-5) of the tuyeres of equal oxygen consumption. This makes it possible to install: insert heads with slot-hole nozzles instead of multichannel ones, using feed pipes of the same dimensions. In addition, nozzles with a large width-to-length ratio are more difficult to cool, since with the growth of this

312359

The ratio increases the lateral surface of the nozzle walls. In this case, a supersonic slit nozzle with a given width-to-length ratio is optimal from the viewpoint j of oxygen absorption of the bath. The strut has a sufficiently large surface and, at the same time, possesses a large rigidity necessary to achieve the required depth of penetration of oxygen into the metal, and the area above the top 19. 4 of the reaction zone in this case is maximized.

The absorption of oxygen is largely determined by the size of the surface area of the implanted gas jet. Therefore, the use of a chip-like supersonic nozzle will provide a higher absorption of oxygen by blowing a bath (by 10–15%). The yield is increased by 1-2% and is 92-93%.

FIG. g

FIG.

Editor I. Derbak

Compiled by A. Kakhanov Tehred L, Oleinik

Order 3062/24 Circulation 552Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5,

Production and printing company, Uzhgorod, st. Project, 4

Correction. Roshko

Claims (1)

FURMA containing concentric pipes forming oxygen supply, cooling water supply and drain paths, a head with a nozzle connected to the oxygen supply path, characterized in that, in order to increase the dynamic pressure of the outgoing gas stream, increase the resistance of the lance head due to the creation of supersonic gas outflow velocities and a decrease in the gas velocity attenuation along the length of the jet core, the tuyere nozzle in the cross section is made in the form of an oval slot with the ratio of axes in the critical section 1: (5-7), and in the longitudinal section according to the Laval nozzle. SU, „1235919 A FIG. f