GB2257780A

GB2257780A - Keeping free a lance opening of a metallurgical vessel

Info

Publication number: GB2257780A
Application number: GB9214625A
Authority: GB
Inventors: Dipl-Ing Norbert Ramaseder; Dipl-Ing Johann Steins
Original assignee: Voest Alpine Industrienlagenbau GmbH
Current assignee: Primetals Technologies Austria GmbH
Priority date: 1991-07-16
Filing date: 1992-07-09
Publication date: 1993-01-20
Anticipated expiration: 2012-07-09
Also published as: JPH0657850B2; ITMI921703A1; ATA142891A; DE4220306C2; DE4220306A1; ITMI921703A0; GB2257780B; JPH05195036A; GB9214625D0; AT395984B; IT1255424B

Description

1) ú1377 31 Arrangement for Keeping Free a Lance Opening of a

Metallurgical Vessel The invention relates to an arrangement for keeping free a lance opening passing the wall of a metallurgical vessel and provided for a lance carrying a measuring and/or sampling probe, with the lance being removed from the metallurgical vessel.

A converter having a lance opening is known from EP-A 0 079 290. The lance opening is to enable the quick introduction of a probe for the purpose of taking a sample or for the purpose of measuring the temperature or effecting measurements of other parameters. A separate opening for the introduction of the lance is suitable, in particular, if the mouth of the converter is only difficult to accede, thus requiring special time-consuming manipulations.

In practice, it has proved that lance openings of this type close up every now and then, since slag deposits there, forming compounds with the lining of the converter. The removal of such deposits involves much work and time, which is particularly disadvantageous with a lance opening, because measurements and samples have to be taken very quickly in order to be able to influence the metallurgical process occurring within the metallurgical vessel in time and on purpose. This holds, in particular, for the production of steel in a converter.

From DE-C 39 34 340 it is known to minimize the growth of deposits at a lance opening of a converter and to facilitate the removal of possibly forming crusts by providing the lance opening with a lining of graphite or of a graphite-alumina mixture. To avoid slag spittings, the lance opening is closeable by a lid.

The invention has as its object to provide an arrangement of the initially defined kind, by which deposits and skulls of any kind can be safely avoided even with metallurgical vessels having a conventional brickwork, such that no cleansing work whatsoever has to be carried out at the lance opening before introducing a lance through the lance opening, and measurements as well as samples can be taken within as short a time as possible. In addition, spittings as may particularly occur during blowing in the production of steel in a converter are to be avoided.

This object of the invention is solved in that the arrangement comprises a means for generating a flame and/or a gas jet, which means is displaceable by a displacement means from a resting position lateral of the lance opening into an operating position closing the lance opening.

When using a burner, all of the material that gets into the lance opening in the liquid state can be removed from the lance opening in the liquid state such that this material has no chance of adhering to the wall of the lance opening. If a gas jet is provided, a gas cushion will form within the lance opening, which prevents material from penetrating into the interior of the lance opening from the very beginning.

From DE-C 26 39 712, an arrangement for closing a tap hole during casting of melt from a metallurgical vessel is knwon, which comprises a closure body fastened to a pivot arm and pivotable with the same into a position delimited by stops, in which an annular gap of a predetermined size is left between the closure body and the tap hole. A compressed gas may be injected through the closure body having a cross section that tapers towards the mouth of the tap hole. By aid of the compressed gas, melt flowing out of the tap hole during tapping is urged back into the interior of the metallurgical vessel. Air is sucked into the interior of the tap hole through the annular gap in order to burn off skulls forming at the tap hole-.

To speed up the introduction of the lance into the metallurgical vessel, the arrangement advantageously comprises a funnel, which is alternatively movable by a moving means to the means for generating a flame and/or a gas jet, from a resting position il lateral of the lance opening into a position in alignment with the lance opening.

A structurally particularly simple embodiment is characterized in that both the means for generatinga flame and/or a gas jet and the funnel are movable by one and the same moving means, wherein the means for generating a flame and/or a gas jet and the funnel advantageously are commonly arranged on a carrier engaged by the moving means.

The carrier suitably is arranged to be movable on a trestle located beside the metallurgical vessel.

According to a preferred embodiment, the carrier is designed as a hood pivotably fastened to the metallurgical vessel.

A structurally simple variant is characterized in that a funnel is rigidly mounted on the lance opening and that the means for generating a flame and/or a gas jet is introducible into the funnel, the means for generating a flame and/or a gas jet suitably being pivotably hinged to the metallurgical vessel.

The funnel advantageously includes a lateral recess through which the means for generating a flame and/or a gas jet may be pivoted into and out of the funnel.

In case of particularly long lance openings, which result if the axis of the lance opening encloses a very acute angle with the central axis of the metallurgical vessel, the means for generating a flame and/or a gas jet advantageously comprises an adjustment means, by which it is insertable into, and retractable from, the lance opening.

In the following, the invention will be explained in more detail by way of several exemplary embodiments and with reference to the drawing, wherein Fig. 1 is a partially sectioned side view of an arrangement according to the invention according to a first embodiment provided at a steelworks converter and Fig. 2 4 - represents a section along line II-II of Fig. 1. In Fig. 3 the flame jet positioned in the lance opening is shown in an illustration analogous to Fig. 2. Fig. 4 represents a second embodiment in the side view and Fig. 5 is a section along line V-V of Fig. 4. Another embodiment is illustrated in Figs. 6 and 7, Fig. 7 being a sectional view along line VII-VII of Fig. 6.

A lance opening 1 for introducing and removing a measuring and/or sampling probe mounted on a lance passes the wall 2 of a metallurgical vessel designed as a steelworks converter 3 in the vicinity of its mouth. The wall 2 of the steelworks converter 3 is formed by a shell 4 of steel, on whose internal side a refractory lining 5 is provided. In the region of the lance opening 1, a connection piece 6 is welded into the shell 4, which also is provided with a refractory lining 5 on its internal side.

According to the embodiment illustrated in Figs. 1 to 3, a hood 7 is pivotably arranged on the connection piece 6, surrounding the connection piece 6 on its external side and being formed by two parallelly arranged side walls 8, 9 and a front wall 10 connecting the side walls. One (8) of the side walls 8, 9 is pivotably mounted on the connection piece 6 via a pivot 11; the second side wall 9 suitably is supported on the connection piece 6 via a link guide 12 allowing for pivotal movement about the pivot 11. Pivoting of the hood 7 is effected by aid of a pressure medium cylinder 13, which, on the one hand, is hinged to the shell 4 of the steelworks converter 3 and, on the other hand, is hinged to the hood 7.

A funnel 16 and a burner 17 - for which the hood 7 constitutes a support are arranged on the front wall 10, which covers the external-side mouth 14 of the lance opening 1 by a slight distance 15 in any pivoted position of the hood 7, wherein, in a first pivoted position of the hood 7 (cf. Figs. 1 and 2) the funnel 16, and in a second pivoted position of the hood (cf. Fig. 3) the burner 17, are placeable above the lance opening 1 and in alignment with the same.

The funnel 16 serves as an auxiliary means for introducing the lance into the interior of the steelworks converter 3 so that the lance can be introduced into the lance opening 1 as quickly as possible without requiring centering manipulations.

The burner 17 serves to generate a burning jet 18 within the lance opening 1 during that time at which no lance passes the lance opening 1. The effect of the burning jet 18 is to make material that gets into the lance opening 1 not to deposit there, but to flow back, in the liquid state, into the melt bath present within the steelworks converter 3.

If the lance opening 1 has a greater length 19, which is the case, in particular, if the axis 20 of the lance opening is oriented to the shell 4 of the steelworks converter 3 at a very acute angle 21, the burner 17 advantageously is introducible into the lance opening 1. For this purpose, the burner 17 is arranged in the interior of a cylinder 22 rigidly fastened to the hood 7. The burner 17, on its outer side, is provided with an annular plate 23 forming a piston to be moved into an upper and a lower end position when actuated by ducts 24, 25 running into the cylinder. Both end positions are defined by stops 26, 27 arranged within the cylinder 22. In the upper end position, which is illustrated in Fig. 1 by full lines and in Fig. 3 by broken lines, the burner 17 is in the retracted position and the hood 7 may be pivoted.

The combustion gas supply duct 28 passes the upper cover wall 29 of the cylinder 22 and is sealed relative to the same by a seal 30. The burner 17 is sealed by a seal 31 relative to the opening provided in the hood 7, which it passes even in the retracted position.

Instead of the burner 17, a gas-jet generating means could be provided, which likewisely might be arranged to be introducible into, and retractable from, the lance opening 1 by a pressure medium cylinder in a manner similar to the burner. The gas jet prevents slag and other spitted material from penetrating the lance opening. It has proved that, with lance openings 1 of conventional dimensions, a gas supply of between 4 and 5 standard cubic meters/minute will do to build up a gas cushion that keeps the lance opening free of deposits.

According to the embodiment illustrated in Figs. 4 and 5, the funnel 16 is stationarily fastened to the upper end of the connection piece 7 and has a narrow lateral recess 32, which, however, does not extend as far as to the base of the funnel and through which the cylinder 22 containing the burner 17 and articulately connected to the front plate of the connection piece is placeable into a position registering with the lance opening 1 by an adjustment means 33 designed as a pressure medium cylinder.

According to the embodiment represented in Figs. 6 and 7, the hood 7 is arranged on a trestle 34 located beside the metallurgical vessel, e.g., on a housing surrounding the converter, which is also called doghouse.

The invention is not limited to the embodiments illustrated, but may be modified in various aspects. For instance, it might also be possible to mount a stopper to the hood 7, which stopper is introducible into the lance opening 1. Furthermore, it is not absolutely necessary to provide a funnel 16; on the other hand, the burner 17 to be pivoted into the funnel 16 according to Figs. 4 and 5, together with the funnel 16 might be arranged on the hood 7 in addition to other means, such as a stopper.

Claims

Claims:

1. An arrangement for keeping free a lance opening (1) passing the wall of a metallurgical vessel (3) and provided for a lance carrying a measuring and/or sampling probe, with the lance being removed from the metallurgical vessel (3), characterized in that the arrangement comprises a means (17) for generating a flame and/or a gas jet (18), which is displaceable by a displacement means (13, 33) from a resting position lateral of the lance opening (1) into an operating position closing the lance opening.

2. An arrangement according to claim 1, characterized in that it comprises a funnel (16), which is alternatively movable by a moving means (13) to the means (17) for generating a flame and/or a gas jet (18), from a resting position lateral of the lance opening (1) into a position in alignment with the lance opening (1).

3. An arrangement according to claim 2, characterized in that both the means (17) for generating a flame and/or a gas jet (18) and the funnel (16) are movable by one and the same moving means (13).

4. An arrangement according to claim 3, characterized in that the means (17) for generating a flame and/or a gas jet (18) and the funnel (16) are commonly arranged on a carrier (7) engaged by the moving means (13).

5. An arrangement according to claim 4, characterized in that the carrier (7) is arranged to be movable on a trestle (34) located beside the metallurgical vessel.

6. An arrangement according to claim 4, characterized in that the carrier (7) is designed as a hood pivotably fastened to the metallurgical vessel (3).

8

7. An arrangement according to claim 1, characterized in that a funnel (16) is rigidly mounted on the lance opening (1) and that the means (17) for generating a flame and/or a gas jet (18) is introducible into the funnel (16) (Figs. 4, 5).

8. An arrangement according to claim 7, characterized in that the means (17) for generating a flame and/or a gas jet (18) is pivotably hinged to the metallurgical vessel (3).

9. An arrangement according to claim 8, characterized in that the funnel (16) includes a lateral recess (32) through which the means (17) for generating a flame and/or a gas jet (18) may be pivoted into and out of the funnel (16).

10. An arrangement according to one or several of claims 1 to 9, characterized in that the means (17) for generating a flame and/or a gas jet (18) comprises an adjustment means (22), by which it is insertable into the lance opening (1) and removable from the lance opening (1).

11. Apparatus for keeping open a lance opening in the wall of a metallurgical vessel, substantially as hereinbefore described with reference to Figs. 1 to 3, Figs. 4 and 5, or Figs. 6 and 7 of the accompanying drawings.