WO1986000978A1

WO1986000978A1 - Equipment for the remaking and repairing of high furnaces

Info

Publication number: WO1986000978A1
Application number: PCT/BE1985/000013
Authority: WO
Inventors: William Pasek
Original assignee: Stephan Pasek & Cie, Societe Anonyme
Priority date: 1984-07-24
Filing date: 1985-07-08
Publication date: 1986-02-13
Also published as: EP0226576A1; FR2568361A1; AU4635685A; NO861164L; NO167479B; AR242446A1; EP0226576B1; FR2568361B1; ES545296A0; ES8701964A1; DE3571498D1; KR860700288A; BR8507216A; NO167479C; ATE44607T1

Abstract

Equipment intended to the remaking and repairing of high furnaces (1) comprising a rotating feed launder (7). The equipment comprises a telescopic projection length (21) which is controlled and mounted on the rotating feed launder (7) and which may be expanded in order to reach, by the combined rotation and inclination of the feed launder (7) and the expansion of the length (21) all the points of the high furnace (1) requiring a treatment. Application to the remaking or repairing of the refractory lining of high furnaces.

Description

EQUIPMENT FOR THE FACTORY AND THE SERVICING OF TOP STOVE.

The present invention relates to removable equipment intended for repair work, and repair of blast furnaces, in particular by gunning, in which the load distribution is carried out by a rotating chute mounted in the louver. The invention also extends to a method of repairing and repairing blast furnaces of this type.

It is known that modern blast furnaces generally include devices for charging and distributing the supplied materials (ore, coke and fluxes) constituted by a rotating chute which allows better distribution of these charges and therefore better regulation of the blast furnace market. Blast furnaces of this type, however, just like conventional blast furnaces, require repairs or repairs to the lining or refractory lining of the walls of the top of the tank in particular. These operations may be particularly necessary when the blast furnace has worked "at the periphery" causing maximum production of cast iron but also wear of the refractory lining which is very significantly greater than during a central operation of the apparatus.

Document US-A-4 253 646 discloses a device for repairing the refractory lining of a blast furnace, which comprises a horizontal fixing device which can be introduced into a lateral opening adjacent to the upper end of the top furnace and which carries a first rotary and pivotable arm to which is articulated a second arm provided at its free end with a projection nozzle. The device described nevertheless includes complicated and expensive drive mechanisms for controlling the various movements of the arms. In addition, it is necessary to assemble a complicated and bulky device before each repair operation of a blast furnace. In addition, as mentioned in the document CA-A-1 169 382 commented below, the use of the device claimed in the document US-A-4 253 646 requires the disassembly of the loading chute, when it is a blast furnace with a rotary loading chute, while this type of unloading device is increasingly used.

In addition, the above-mentioned device is intended to be introduced laterally into the blast furnace, through an opening in the wall, and cannot be used for access from above.

By document CA-A-1 169 382? there is known a device for repairing the refractory lining of a blast furnace, which comprises a horizontal member introduced by a lateral opening of the blast furnace, at the upper end thereof, a telescopic median shaft rotatably mounted to said member horizontal, drive means for the extension and retraction of said median shaft, for driving said shaft in rotation on its axis and for tilting an adjustable projection nozzle fixed at the end of said median shaft which can moreover be moved along the diameter of the blast furnace at this section. Although said document refers to the device mentioned in document US-A-4 253 640, while seeking to simplify it, it still uses a complicated and expensive arrangement provided with numerous controls, which is introduced laterally at the top furnace, at the upper end of it. Document GB-A-2 034 605 discloses a spraying installation for the hot repair of metallurgical vessels, in particular an oven for implementing the DH or RH degassing process. It claims more particularly a particular characteristic of the projection lance.

The device described therein is more particularly suitable for the repair of converters which are substantially different from blast furnaces.

The device described in the aforementioned document could not find an application in a blast furnace with a revolving chute and, consequently, another more suitable solution had to be sought to support and guide the projection head of a conventional type.

The present invention aims to provide equipment and a method for carrying out emergency operations of extremely rapid repair and repair of a blast furnace while avoiding the need to introduce operators into the blast furnace. The object of the invention is also to allow, in particular, to carry out the necessary repairs and repairs without having to wait for the complete cooling of the blast furnace, which, of course, saves considerable time.

Another object of the present invention is to provide a new device or equipment of the aforementioned type which is suitable for a blast furnace equipped with a rotating chute, but which does not have the drawbacks of the known devices introduced laterally into the blast furnace. These objectives are achieved by equipment comprising a controlled telescopic projection lance which is mounted on the rotating chute (namely in this one or outside thereof), "which can be deployed in order to reach, under the combined effect of the rotation and the inclination of the chute and its deployment, all the points of the blast furnace requiring treatment. The principle on which the invention is based is therefore to combine two movements specific to the rotating chute , namely rotation and inclination with a clean movement of the lance, namely deployment, in order to be able without human intervention in the interior of the blast furnace to carry out the necessary operations. These operations can of course be observed by an external operator using conventional devices, in particular at least one camera and a display screen arranged outside the blast furnace. Armored cameras, waterproof and protected by a current of fresh air, introduced inside the blast furnace, which will be mounted for example on the chute or any other place and which will give a front view and / or in profile of the refractory projection.

Advantageously, the deployment of the telescopic lance is ensured under its own weight, one. restraining force being exerted by a cable controlled from the outside. Other devices are of course conceivable.

The telescopic lance preferably consists of tubes with a square section and has, outside the lance, a curved projection head. In said square section tubes are housed the conduits bringing to the projection head suitable materials such as that of the dry refractory material and water in the case where it is desired to carry out a refractory gunning. The lance can of course also be used to spray other fluids or chemicals. Said lance can also be adapted for the projection of refractory materials put in a state of prefusion at the exit of the projection nozzle and this by various techniques, in particular by plasma, incandescence by exothermy, or blowtorch. Advantageously, said lance is attached to the stiffening elements of the chute which brace the upper edges of the chute. If necessary, additional spacers can be added to the chute to support said lance. According to a specific aspect of the present invention, a product is provided for repairing or repairing a blast furnace comprising a rotating chute, characterized in that equipment of the type described in the chute is fitted and provides the repair treatment or desired repair by associating with the proper movements of the chute, a deployment movement of the lance.

Advantageously, the refection or repair treatment is provided by working from top to bottom in the tank of the blast furnace. This procedure has the advantage that the non-adherent or superfluous materials fall freely to the bottom and on the other hand that any excess water which descends under the effect of gravity is incorporated into the material brought later. By working in reverse, the trickling water, during the progress of the work, would destroy, by the loss of water due to gravitation, the good water-cement balance during the beginning of setting. Therefore, the last upper crowns would have a very poor quality of concrete and in particular a friability at the place even where very high abrasion resistance is sought.

It should be noted that the term repair or repair treatment must be understood in the broad sense and includes operations other than spraying by the technique known as gunning of refractory materials, cold or hot. The lance can in particular be used to carry out a blasting in order to clean the walls of bricks or shielding or crown of dust and adherent materials of all kinds and to update the healthy body of the refractory coating before proceeding to a guniting.

Various characteristics and specific advantages of the invention will appear to those skilled in the art on reading an illustrative description of a particularly preferred embodiment of the invention, with reference to the accompanying drawings . In these:

Figure 1 shows a partial schematic view of an upper half of a blast furnace with the chute and the equipment according to the invention in a first position.

Figure 2 shows a view similar to that of Figure 1 with a lance in the partially deployed position.

Figure 3 is a view similar to Figure 1 with another form of relaying of the equipment according to the invention.

Figure 4 is a perspective view of the chute equipped with the lance according to the invention.

Figure 5 is a detail view in elevation of a gunning head in particular.

In the various figures, identical reference marks are used for them. same or similar items. We recognize in the mouth 3 of a blast furnace represented by the general reference 1, essentially the upper left part with respect to its vertical axis 5. In the mouth 3 is mounted in the conventional manner a chute 7 which is designed to so as to be able to undergo a rotational movement substantially around the axis 5 and to be able to oscillate on the articulation point 9. The level of the upper work floor is indicated by the reference 11 and from this floor there is access to an inspection hatch 13 normally provided in the window 3 for any repairs to the chute 7. This inspection hatch will advantageously be used to mount the equipment of the invention. This equipment is essentially constituted by a telescopic lance 21 formed of square section tubes and provided at one end with a projection head 23 of curved shape. A cable 25 is wound around a winch 27, preferably a pneumatic winch, to allow the cable 25 to run smoothly.

In the embodiment of Figure 2, there is shown the telescopic lance 21 as consisting of four telescopic sections. It should be understood, however, that a different number of sections can be provided, the length of the sections and their number having to be chosen so that the lance can reach the different points subjected to the repair or repair operation.

Adequate elements, for example retaining chains, are of course provided so that the different sections or sections of the lance 23 cannot disengage. These elements can either be constituted by stops or by chains retaining the sections so that a length sufficient section. of the lance remains in the previous section. The head 23 of the lance is designed so as to be able to direct a jet, in particular a gunning jet in the manner shown in FIG. 2. It will be appreciated that by acting on the rotation and the inclination of the chute and by deploying adequately lance 21, it is possible to reach any desired point inside the blast furnace, the lower limit of the point which can be reached in the tank being of course determined by the possibility of deployment of the throws 21.

Advantageously, the deployment of the lance is ensured under its own weight, by unwinding the cable 25 using the winch 27. The ascent of the lance is obtained by winding the cable 25 on the winch 27. In the interior of the launches, at least two conduits are provided, on the one hand for the supply of dry refractory materials and on the other hand for the supply of water or other fluids. Other conduits can also be provided, in particular accessory conduits for the projection of a blasting material or for the circulation of a cooling fluid.

The various flexible conduits identified by the reference 29 are taken up by return pulleys 31 and 33 in the upper part of the top and are brought to a conventional supply device (not shown).

As indicated, the process of the invention takes place (possibly after a shot peening operation intended to update the sound part of the coating, by causing a projection by gunning of an adequate refractory material) from top to bottom. bottom or, depending on the quality of the materials and the spraying method adopted, preferably from bottom to top by causing the telescopic rise of the lance previously deployed. The variant embodiment of FIG. 3 comprises a lance 21 suspended from the end of the chute 7 and held by jacks 51 preferably arranged on either side of the chute possibly after reinforcement of the latter and allowing thus to modify the angle of inclination of the lance relative to the chute. By acting on the inclination of the trough 7 and on the jacks 51, it becomes on the one hand possible to treat with great precision points or particular areas of the blast furnace and in particular to carry out interventions, emergency or routine, at great depth, for example greatly exceeding the -6500 mm level below the blast furnace shock crown. This embodiment illustrates the great flexibility of work possible by the installa¬ tion of the invention, the combined action of the inclination of the chute and the jacks makes it possible to reach even in great depth the areas in front have an intervention. The proper design of the telescopic lance is of course adapted to the function to which it is intended and to the constraints to which it will be subjected. Not only the length of the sections but also their section, their thickness, the quality of the steels chosen will be calculated according to the desired spans and the loads to be supported. If retaining chains are provided to prevent disengagement of the sections of the lance, they will also be calculated in an adequate manner while taking care to preserve a sufficient engagement for example of approximately 1 m of each section of lance in the upper element. In Figure 4, there is shown how the lance 21 is mounted in the chute 7. This assembly is advantageously done by suspending the lance 21 to the stiffening spacers 41 and 43 which are generally permanently mounted at the ends of the chute. If necessary, it is possible to provide additional spacers such as those indicated at 45. The design of the projection head 23 is illustrated in FIG. 5. Its essential characteristic is the fact that a rounded chamber 55 is arranged in its body which partially fills with the projected material, thereby protecting this body from wear and tear under the effect of the admitted material. It is found that heads of this type where material-to-material contact is ensured can resist without significant abrasion for considerably longer periods of time.

This head can of course be fitted with a spout (not shown) of suitable shape and is particularly effective for working in positions similar to those illustrated in FIG. 2.

Although there is shown a preferred embodiment of the invention, it should be understood that many alternative embodiments remain possible ^ ^{~ ~} variants are especially possible in terms of the techniques used for the execution of repair and repair operations within the meaning of the invention. Variations are also possible in terms of the design of the equipment itself, provided that the functions described are carried out.

Claims

claims

1. Equipment intended to allow the repair and repair of blast furnaces (1) comprising a rotating chute (7), said equipment comprising a controlled telescopic projection lance (21), characterized in that said telescopic projection lance is mounted on the rotating chute (7) and can be deployed in order to reach, under the combined effect of the rotation and the inclination of the chute (7) and its deployment, all the points of the blast furnace (1) requiring a treatment.

2. Equipment according to claim 1, characterized in that it comprises at least one camera preferably arranged on the chute (7) in the axis of projection of the lance (21) and a display screen arranged outside from the blast furnace.

3. Equipment according to any one of claims 1 or 2, characterized in that the deployment of the telescopic lance (21) is ensured under its own weight, a retaining force being exerted by a cable (25) controlled from outside.

4. Equipment according to any one of claims 1 to 3, characterized in that the telescopic lance (21) consists of tubes with square section and in that a curved projection head (23) at the desired angle is mounted at the end of said lance (21).

5. Equipment according to claim 4, characterized in that in said tubes with square section of the lance (21) are housed the conduits (29) bringing to the projection head (13) suitable materials.

6. Equipment according to any one of claims 1 to 5, characterized in that said lance (21) is attached to the stiffening elements (41, 43) of the chute (7), which brace the upper edges of said chute (7).

7. Equipment according to claim 6, characterized in that additional spacers are added to the chute (7) to support said lance (21).

8. Equipment according to any one of claims 1 to 5, characterized in that said lance (21) is suspended at the end of said chute (7) and that jacks (51) make it possible to modify the angle inclination of the lance (21) relative to the chute (7).

9. A method of repairing or repairing a blast furnace (1) comprising a rotating chute (7), characterized in that an equipment according to any one of claims 1 to 8 is mounted on the chute (7) and provides the desired repair or repair treatment by associating the movements of the spout with a movement for deploying the lance (21).

10. Method according to claim 9, characterized in that the repair or repair treatment is carried out by working from top to bottom in the tank of the blast furnace (1).