JPS58171522A - Introduction of gas flow into vessel of molten metal and valve assembly therefor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] This discussion is directed to methods of introducing substances into molten metal.

More particularly, the present invention relates to a method for entraining powdered solids into a molten metal in a six-gas stream.

An example of such a method is the injection of calcium silicide into molten steel.

The method currently in use is to form a refractory member, known as a lance, before it is normally used. This method uses a long and thin tube. 4 Herons are subject to significant wear, fist damage, and slag damage, and even if they are only immersed in molten steel and slag for a very short time, their lifespan is limited. It is.

According to the invention, a gas stream is introduced under pressure into an introduction channel in the vessel wall of the molten metal, and a valve is actuated to open the channel so that the gas stream is introduced into the molten metal. A method is provided for introducing a gas stream comprising a gas into a container of molten metal.

The gas stream may have powdered active material entrained therein. For example, the argon gas stream can contain calcium silicide, especially on the desulphurization side. Another example may include quicklime in a stream of argon or other inert gas.

Preferably, the valve would be adjustably operable to change the cross-sectional area of the flow path and adjust the gas flow direction.

Advantageously, the flow passages and valves are defined by separately formed refractory structures. Therefore, the present invention further provides:
a refractory casing sized to fit an opening in the lower part of a container for molten metal and defining an inlet flow path in the container, a valve member closing the wrinkled flow path, and moving the valve member into an open position and a closed position. A valve assembly is provided for introducing a gas flow into a container of molten metal comprising means for opening and closing the flow path.

In one embodiment of the invention, the flow path has an enlarged zone that defines an upper valve seat, with respect to which opening and closing of the multiple flow paths is achieved by movement of the valve. In yet another preferred variant of the invention, a further valve seat is provided at the bottom of the expansion zone. If the gas flow stops when the valve opens, the hydraulic pressure of the molten metal (head)
causes the valve to seat in the lower valve seat, thereby closing the flow path.

To explain the box shown below, the lower part 2 of the ladle for molten metal
The opening 1 is a cylindrical 7' o-k 3. That is, it is lined with a well-shaped block of refractory material.

This block 6 holding rim 4 and a protrusion (rebat) supported by an inward protrusion @6 at the bottom of the metal ladle at the bottom
・) has 5. This well F” shaped block is socket 7
The valve assembly has a frustoconical refractory casing of a valve assembly according to the present invention. The casing consists of two separately formed frusto-conical upper and lower members 8 and 9, both having complementary stepped mating surfaces. The lower member 9 has a relatively wide channel 10 arranged vertically in use and an inwardly extending metal supporting medium 12 which is secured to the ladle by a lug 26 with a refractory ring 11 as an intermediary. It has a lower surface supported above.

The upper member 8 has one DC flow path 16 narrower than 0.

The golden valve assembly can be housed within a golden maple shell for ease of mounting and handling.

Channels 10 and 13 are enlarged 5 to define a chamber 14 in their opposing zones. W114 is a truncated conical portion 1 that defines the upper and lower sockets that constitute the valve seat.
5 and 16.

The valve member or body is an elongated refractory member with a central cylindrical zone 7 and upper and lower conically tapered valve portions 11 and 19. Its lower part 19 has a rounded keyway 2o into which the enlarged head 22- of the valve stem 21 slides.

During sliding, the valve stem is slid 900 revolutions from the position shown into the groove located at the position shown. A retaining nut 23 screwed onto the valve stem 21 secures the valve body to the valve stem. The valve body is located in the upper conical valve seat 15 and is connected to the flow path 10.1.
The top closed position is shown with M closed. To completely close the valve, the valve body and enlarged head are retracted to a position such that the clearances between the abutting walls of the valve body and the upper and lower valve seats, respectively, are equal. To achieve this,
The distance traveled by the valve stem is approximately 2.5G.

The valve stem 21 extends rearwardly through a bearing seal 24 which, together with a downwardly extending portion 25 of the canister 12, connects the ends of the passages 10, 13 to one end of the drive lever 27 in a pill-type manner. Concatenate by. The drive lever 27 is 2
It has a fulcrum at 8, and the other end is connected to a hydraulic ram or other ram 29 in a pimet manner. Bearing seal 24C)
An upwardly inclined introduction channel 60 for supplying gas and entrainment substances is provided at the top.

In use, at the position shown, the introduction of the gas stream and the substances entrained therein, such as alponic acid and calcium silicide, is initiated. The valve body on the valve stem is retracted to an open position to allow gas flow to flow between the valve body and both the upper and lower valve seats and into the flow path 1δ. Since the degree of opening of the valve can be adjusted continuously.

Gas flow rate can be precisely controlled. The gas and entrained substances are thus injected under pressure into the molten metal in the ladle. After injection, the gas supply is terminated by advancing the valve to the closed position If. The gas flow moving forward in the flow path is ll1l! It
It will be appreciated that this prevents the metal from escaping due to the force. Thus, the gas will be injected at a pressure sufficient to disturb the rest of the i1 plane of the molten metal in the ladle and cause mixing of the gas flow and the metal. Pressures of 4 to 8 atmospheres are often used. Valve body can be opened or closed by spring 1iK
It can also be unevenly distributed. The more the valve body retreats, the larger the retreating force becomes due to the uneven distribution force of the ram and spring (spring bias).
) occurs, an emergency seating of the lower valve part 19 on the lower valve seat 16 is achieved, K thereby closing the flow path 10.

Components identified as "refractory", such as components 8 and 9, are preferably cast from a suitable refractory slurry based on refractory aggregates. Aluminum-based refractories are suitable because they have good resistance to thermal shock. However, any refractory suitable for a molten metal environment can be used.

In another @a, the valve stem 21Fi fits into the channel 10 and extends in the longitudinal direction guided by the channel 10!
has. In this case, gas flows through these lip grooves. The well-shaped block 3 can be secured against forward movement by means such as hooks or melts.

A gas flow can be introduced into the ladle by introducing an active substance, for example a wire, through a hole in the valve stem and the valve body, so that it appears in the channel 13.

BRIEF DESCRIPTION OF THE DRAWINGS The drawing is a cross-sectional view of an example of a valve assembly according to the invention, shown as it is placed at the bottom of a ladle for molten metal. 2-Jll pot lower part, S・-cylinder block lining, 7-socket, 8,9-valve casing member, 10.125-channel, 11-refractory ring, 12
-Canister-, 14-valve chamber, 15.16-valve seat,
17.18.19・-Valve body, 20-Keyway, 21-
Valve stem, 22-enlarged head, 23-nut, 24-bearing seal, 27-drive lever, 29-hydraulic ram,
50-Gas and entrained substance introduction channel.

Claims (1)

[Claims] 1. A gas flow is caused to flow under pressure into an introduction channel in a wall of a molten metal container, and a valve is actuated to open the channel to allow the gas flow to flow into the molten metal. A method of introducing a gas stream into a container of molten metal by introducing a gas stream into a container of molten metal. 2. The method according to claim 1, wherein the gas stream entrains solid particulate matter. 8. A refractory casing having dimensions such that the valve used reduces the gas flow rate from the closed state to the lower opening of the container for molten metal, and which limits the introduction flow path in the container; a valve assembly port 5 for introducing a gas flow into the container of molten metal, comprising a valve member for closing the valve member and means for moving the valve member to open and closed positions to open and close the flow path; 5. A valve assembly according to claim 4, wherein said flow path has an enlarged zone defining at least one valve seat. 6. The valve assembly of claim 181, wherein the valve member has a conical portion with a tip and the valve seat is a correspondingly tapered conical socket. ? - A valve assembly according to claim 5 or claim 6, having a front valve seat for regulating the gas flow rate and a rear valve seat for actuation to close the flow path in an emergency. 8. According to any one of claims 5 to 7, wherein the flow passage with an enlarged zone defining the valve seat is defined between upper and lower separately formed refractory blocks. Valve assembly. 9. Claims 4 to 8, in which the valve body is mounted on the end of a reciprocating valve stem that can be operated from outside the flow path.
Claim 9: The valve assembly 10 according to any one of the above claims, wherein the valve stem is surrounded by an annular gap formed by a flow path, and a side hole in a rearward extension of the flow path provides an inlet for gas flow. 〇