SE452906B - DEVICE FOR SUPPLY OF POWDER AND / OR GRANULATE OR MIXTURES THEREOF TO METAL MELTS - Google Patents

Description

hrs) 452 906 safety under working conditions is unsatisfactory. Furthermore, it requires take system frequent repairs and maintenance work.

The object of the invention is to provide a device for loading or feeding of powder or granular material, even in the case of grain size is not homogeneous, and especially with variable production volumes of choice there.

The object of the invention is achieved by means of a device which contains a tank and a loading unit, the tank being provided with a lower part with decreasing cross section, preferably a conical part, and at least one mouthpiece piece and an ejector arranged on this part of the bottom with the ejector above the nozzle, the nozzle or nozzles being connected to a carrier gas line and the ejector with a mixture transporting pipeline.

The ejector used in the charging unit is suitably a two-stage ejector, and a guide funnel with decreasing cross-section, preferably one conical funnel, is arranged in the lower part of the tank, the upper part of the funnel being covered with a metal sieve or a perforated plate. The steering wheel can be bottom with a vibrator.

The tank in the device according to the invention is in some cases provided with a built-in scale, preferably an electronic one.

In a suitable embodiment of the device according to the invention, connected to at least one mixing bunker, in which rotating mixing leaves or wings are provided.

The mixing bunkers or tank are preferably connected to the loading containers, and these in turn with separate loading units. The se- are suitably connected to a regulating wave.

If the device according to the invention is used for supply or admission of alloying or treatment materials in molten metals is the mixture transporting pipeline is preferably connected to a blowpipe. This consists of a pipe casing surrounding a transport pipe, an elastic refractory layer surrounding pipe casing, a refractory coating and an outer pipe sleeve. A cooling duct is suitably formed between the transport pipe and the pipe casing.

The device according to the invention has a number of advantages over those conventional.

The injection tank makes it possible to regulate the injection intensity within a wide range (10-IÄO kg / min) thanks to the introduced vibrator and the arrangement of the nozzles, which are operated at variable flow rate.

A basic advantage of the device proposed according to the invention one is that the size range of the grains injected with the device can stretch between 0.01 and 4 mm. The result is that the materials used can be produced 452 906 with much lower cost of grinding than required for the devices works within extremely narrow limits for grain size. The invention thus requires grinders that are simpler and, of course, less expensive, and the material can be produced with less manipulation.

Different carrier gases can be used to drive the system, e.g. oxygen, nitrogen and argon. In this way, the application range of the device can be expanded considerably.

A further advantage of the invention is that powder mixtures of free composition and consisting of multicomponent materials of different densities and specific gravity can be fed and loaded with the device. Admission of action or control elements in the metal melt can thus always take place using materials of any composition. At the same time it becomes extremely costly production of the various alloys ("masters alloys ") redundant.

The blowpipe cooperating with the device according to the invention is resistant to extreme mechanical and thermal influences, thereby becomes possible to use unusually long treatment periods, 40-50 min., without risk of breakage, and in addition the pipe is empty. for treatment already below bottling.

Another significant advantage of the device according to the invention is that it is suitable for the rapid and excellent implementation of the various operations and to intensify the process, thus to increase various input devices, e.g. metallurgical apparatus, production capacity ga.

In addition, the device allows efficient use of electrode metal. as well as powdered or decomposed portions of the oxidizing materials and alloys.

In view of the above, it should be appreciated that a considerable saving of material and energy can be achieved using the device according to the invention and that furthermore the precision of the heating and steel production the process can be improved and production efficiency increased.

The new features of the invention will be described and exemplified. in the following with reference to the accompanying drawings, in which Fig. 1 is a schematic representation of an embodiment of the device according to the invention one, while Fig. 2 shows, partly in section, a tank included in the device.

Fig. 1 thus shows a plant arranged for supplying alloy or treatment material for a molten metal. The facility includes container 1, mixing bunkers 2 and a tank 3. The latter is shown in more detail schematically in Fig. 2.

J: 452 906 The tank 3 is designed with a cylindrical upper part Ä and a conical lower part part 5. On the upper side an openable lid 5 is arranged.

The tank 5 is mounted on a stand 7, and on this are electronic scales 8 arranged. On the scales rest in turn brackets 9 attached to the tank 5 side- dove wall.

A conical guide funnel 10 coaxial with the tank 5 is arranged at the conical lower part 5 on the inside of the tank 3. The guide funnel 10 is connected to a (not shown for simplicity) vibrator, which enables the steering wheel to be set in vibration at the selected frequency. The upper part of the steering funnel 10 is covered by one metal mesh or a metal screen ll. To prevent the material from flowing freely, resilient limiting means are arranged between the upper and lower ones the flanges of the guide knob 10 and the wall of the tank 3.

A vertically upwardly directed nozzle 12 is arranged at the lower of the tank 3 part. A double ejector 13 is arranged above the nozzle and connected to one line shelter, which transports the finished mixture.

The nozzle 12 is connected by a pipeline 15 to a central gas cord or with a battery of gas cylinders.

Blow pipes 17 arranged in clamping devices 16 are mounted at it the ends of the mixture transporting line 14. Using these blowpipes the mixture is introduced into the molten metal.

The inner part of a blow pipe 17 is formed by two concentric steel pipes, namely a transport tube provided with fins or ribs on its outside as well an enclosing tube. These fins between the transport pipe and the enclosing pipe casing ensures, on the one hand, that the structure has sufficient mechanical firmness and, on the other hand, they delimit cooling channels if necessary.

The outer part of the blowpipe 17 consists of three layers: an elastic layer on the the casing (it may, for example, consist of an asbestos tape wrapped around the pipe), a refractory layer (preferably of a self-sealing, refractory liquid) and an outer tubular sleeve of refractory material.

The blowpipe 17 thus constructed is capable of withstanding high temperatures. raturer, tom. over 18000 Kelvin, uder ÄO-50 minutes without losing anything of its fire resistance and thermal durability. At the same time, it endures from a mechanical point of view, the stresses to which it is subjected during intense movement during the blowing period.

The plant according to the invention operates in the following manner.

The powders or granules of alloy or treatment material are filled one and one 1 the loading containers 1. These are suitably shaped so that they open automatically when they are placed in their mission positions on the holding re 2}, and the supplied material quantity is set automatically by that scale which are built into each holder. The added material passes through 452 906 to the mixing bunkers 2, where a homogeneous mixture is generated by upcoming mixer blades.

In the case of adding 2-3 types of material, it is sufficient with a single mixing bunker 2, but if several types of material must fed as a homogeneous mixture, two or more mixtures are required bunkers 2 are used, since the number of mission containers 1 that can be connected taken to each mixing bunker 2 is limited. About several mixing bunkers 2 is used, it is advisable to homogenize the mixture by means of an external before mixing it into the tank 3.

The mixing bunkers 2 or one of these are suitably arranged and attached to the tank 3. The mixture is introduced into the latter through a valve or lock, and after the supply the tank 3 is hermetically sealed.

The homogeneous mixture can f.ö. produced and added to the tank 3 also by other means.

Supply of the required quantity is regulated by the devices arranged on the stand 7 electronic scales 8. The amount of material on the metal screen 11 is sufficient, the mission can start. This means that the one with the steering wheel 10 the connected vibrator is switched on, and the result is that the mixture passes through the meshes of the metal screen 11 down into the guide funnel 10, from where it under influence the gas flowing out of the nozzle 12 can escape through the ejector 13, uniformly distributed in the carrier gas.

In the case of the embodiment shown in Fig. 1, the mixture passes to together with the carrier gas to the blow pipes 17 and thence down into the molten metal bath.

The plant according to the invention has many advantages compared to those which previously used to coat molten metals with powder materials.

First of all, grinding to a homogeneous grain size is not required for precise supply or admission and for the material to be in a reliable manner, and thus the production of the powder becomes considerable cheaper and easier.

Since the grain distribution in the added powders is largely non- -homogeneous, they will contain some relatively large grains with large kinetics energy, which practically cleans the pipelines and prevents or eliminates mines temporary congestion.

By applying the proposed method, it becomes possible to quickly and fully carry out various technical operations, to intensify and consequently to increase the specificity of the metallurgical devices output or production.

With the plant according to the invention, the powders and decomposed tier that arise during the transport and storage of the various materials are used significantly better than before.

O\ 452 906 Thanks to the precise and reliable supply and production of selected becomes expensive production of various alloys or "master alloys" superfluous, as treatment materials of the required composition can added directly as powder mixtures.

In the light of the foregoing, it is clear that only the the required quantity of treatment material needs to be introduced into the melts, and the overfeeding commonly applied in conventional technology is unnecessary.

In steel treatment processes, for example, the slag generated in the oven is not replaced (not even partially), and in addition, treatment can start immediately divisible since bottling has begun.

The implementation of the various treatment processes becomes practically depending on the material in the lining of the metallurgical ladles, which correspondingly results in a fundamental improvement in efficiency and economy compared to conventional technology.

The foregoing should also make it clear that the plant according to the invention the different powders and / or granular materials or the admissions of the mixtures more efficiently and more reliably than previously known facilities. In this way, - first and foremost with regard to the tallurgical technology - the various production techniques are considerably simplified and their cost is greatly reduced. In addition, the quality of the products significantly improved.

Claims (1)

Device for feeding powders and / or granules or mixtures thereof, in particular for introducing alloying or treatment materials into molten metals, the device comprising a tank and a loading unit, of which the tank (3) has a lower part (5) with decreasing cross-section, in which part at least one ejector nozzle (12, 13) is arranged near the bottom of the part, the nozzle on the one hand being connected to an incoming carrier gas line (15) and on the other hand to an outgoing transport line (read ) for the mixture accommodated in the tank, which is preferably led to one or more blow pipes (17) for insertion into a metal melt, characterized in that a guide funnel (10), the inlet of which is covered by a metal screen (II) or a perforated plate , is arranged in the lower, tapered part (5) of the tank with its mouth portion surrounding the said ejector nozzle (12, 13), the guide funnel (10) being connected to a vibrator to facilitate the downward feeding of the mixture. ningijmatten, and that the ejector part (lj) of the ejector nozzle is of the double type in order to capture and guide the mixture in two steps known per se.