SE455022B - Use of a highly compacted tube consisting of wood fibre in the form of paper as a lance in metallurgic processes - Google Patents

Abstract

Use of a highly compacted tube (1) consisting of wood fibre in the form of paper as a lance for injection or transfer of solid material and/or gas into smelted metal in metallurgic processes such as iron production processes, where the tube's (1) wall in cross section is comprised of a number of essentially concentric layers of paper, whereby the tube (1) is preferably made out of a so-called helically wound layer of paper tube (2) or entails at least one helically wound paper tube (2), and where the tube is partly or entirely proofed with a fire-resistant substance.<IMAGE>

Description

4 455 022 According to the invention, said tube I thus consists of a material, preferably highly compact, with organic fibers as the main component. The organic fibers are preferably wood fibers in the form of paper.

According to a preferred embodiment, Fig. Ss, the wall of the tube I is formed in cross-section by a plurality of essentially a concentric layer of paper, the tube 1 preferably consisting of a so-called spirally wound paper tube 2, as shown in Fig. 2, or comprises at least one, preferably spirally wound, paper tube 2, as shown in Fig. 3, wherein the tube I consists of six substantially concentrically arranged, preferably spirally wound, paper tubes .

According to the invention, the tube 1 is preferably completely or partially, preferably hot, i.e. throughout the entire pipe wall in this thickness direction, impregnated by means of a refractory substance. The substance may consist essentially of silicates, preferably alkali silicates. especially sodium silicate s.k. water glass. The substance may also consist essentially of an organic substance, such as of the resin type, preferably a silicone resin. for example a hydrogenated ethyl silicate. Of course, other refractory substances are also conceivable.

According to another embodiment, said tube consists essentially of a mixture of organic fibers. for example in the form of wood flour, and refractory substances such as binders. Another binder is also conceivable.

According to a further embodiment, said pipe consists of a pipe of homogeneous wood.

In the case of a pipe consisting of a plurality of concentric layers, the layers can be joined to each other by means of essentially said hard-wearing substance, which in this case serves as impregnation and glue. In embodiments according to Fig. 3, the pipes 2 can correspondingly be joined to each other by means of substantially the substance constituting said impregnation. The layers of each tube can in this case be joined to each other with said substance. Of course, glue of a more traditional kind can be used. In the case of impregnation, a pre-treatment of the pipe with some form of wetting agent may be required, which wetting agent is intended to facilitate the penetration of the impregnating agent, the solid substance, into the pipe.

The function of the lance according to the invention should be substantially apparent from the above. A lance with pipes as above as the main component has proven to be extremely durable in this current high-temperature environment, at the same time as the pipe is manufacturable at loan cost. The impregnation suitably takes place by immersing the tube in a refractory substance.

As will be seen above, a lance according to the invention offers significant advantages over the prior art. It is essential that High Weight is achieved.

The invention has been described above connection to exemplary embodiments. Of course, more embodiments and minor changes are conceivable without departing from the spirit of the invention.

It has been stated above that said fibers are preferably impregnated with a refractory substance. The impregnation should in some cases be dispensable, e.g. then the fibers possess a natural impregnation, which makes the fibers fire resistant. In this case, organic fibers, for example in flour form, can thus be applied by means of a binder. which is not to be described as fire-resistant.

With regard to dimensions of pipes according to the invention, it can be said that a wall thickness t of about 10-50 mm, preferably about 25-35 mm, is in many cases suitable. Suitable ~ is also an inner diameter D; of about 10-50mm, preferably about 1.5-Åm, and an outer diameter Dy of about 50-150mm, preferably about 75-130mm.

Suitable manufacturing lengths and also lahevenance lengths are in many cases 1-2 meters. preferably about 1.5 meters.

The shape of the lance, tube 1 can of course be varied. However, the tube 1 is substantially cylindrical with an internal hole. The lance tip on the right in Fig. 1 can be made, for example, either as shown in full or as shown in dashed lines in Fig. 1 or otherwise.

The invention is thus not to be considered limited to the above-mentioned embodiments but can be varied within the scope specified by the appended claims.

Claims (1)

Use of a highly compact and wood-fiber tube in the form of paper, as a lance for introducing or supplying solid material and / or gas in molten metal in metallurgical processes, such as steelmaking processes, in which the tube (1) wall in cross section consists of a plurality of substantially concentric layers of paper, the tube (1) preferably consisting of a so-called spirally wound paper tube (2) or comprising at least one, preferably spirally wound, paper tube (2), and wherein the tube is completely or partially impregnated by means of a refractory substance. L »