SI9800013A - Reaction pot for aluminothermic preparation for welding tracks - Google Patents

Abstract

The subject of invention is a reaction pot for aluminothermic preparation for the welding of tracks, which is designed as a cylindrical wall (1) of the pot made of sheet metal lined from the inside by a fire-resistant lining (4). The flat bottom of the pot has a centric opening (5) in which there is sealing material. The wall (1) of the pot has a lid (2) and a holding handle (2) and at the same time functions as a transportable container for the welding portion, which can be directly put on the casting die and if necessary fixed to it too.

Description

Reaction crucible for aluminum thermal welding machine

The present invention relates to a reaction pot for an aluminothermic device for welding rails.

In the aluminothermic process for rolling rails, i.e. in the so-called Thermit® melting welding process, they use a chemical reaction to produce hot liquid supplementary material, that is, high affinity of aluminum to oxygen, to reduce heavy metal oxides, preferably iron oxide.

The Thermit® welding portion, the basic components of which are iron oxide and aluminum, is fed into a reaction pot, which is placed above the ends of the rails that they wish to weld and is surrounded by a foundry mold. The aluminothermic reaction takes place after spot ignition with a special ignition stick in the pot within seconds with strong heat developing. The hot reaction products are then separated at about 2500 [deg.] C., with a particularly lighter iron slag floating. The hot liquid Thermit® steel is then poured from the lower end of the reaction vessel fitted with a fusible plug into a mold, welding the ends of the rails there by sealing the ends of the rails and the gap between them.

In principle, any material with any cross section in new products or repairs can be welded using the Thermit® welding process. The aluminum-thermal welding process has gained the widest scope because of its simple and external energy-independent design for rail welding. The welding portion introduced into the reaction vessel is adapted to the profile and material of the rail in terms of quantity and composition. The reaction pot is usually made of magnesite and fitted with a suitable pot stopper. After ignition, the welding portions are placed on a conical shaped reaction crucible with a metal cover and firmly connected to the reaction crucible. A relatively expensive, heavy and complicated rail-mounted holder is provided for fastening the reaction pot, which can be reused several times after the reaction, which allows it to be moved or moved. wrapping the reaction pot around a vertical axis in the region of the casting mold. In total, using a reaction pot requires a greater number of preparation elements, which must be transported to the welding site and assembled there with time-consuming work operations.

EP-B-0 407 240 discloses an aluminothermal welding apparatus that exists from the reaction pot and the casting mold thereof. The crucible is lightly conical at the bottom and is useful for one-time aluminothermic hatching. It has no outer protective jacket and is thus highly exposed to fracture. In addition, it is relatively heavy and therefore difficult to handle on the rail.

The aim of the invention is to create a reaction pot which would be substantially simpler than the previous reaction pots and which would avoid the top of it from being wrapped or folded. expensive holder and would be easier to handle.

The reaction pot of the present invention is characterized by the fact that it is formed of a cylindrical sheath 1 of a pot consisting of a metal sheet and is equipped with a refractory liner 4, with a central opening 5 provided in the flat bottom of the pot equipped with sealing material, wherein the liner 1 of the pot is made with a lid 3 and a carrier handle 2 and at the same time forms a transport container for a welding portion, which can be planted directly on the casting mold and, if necessary, mounted thereon.

The present invention thus creates a transport container for a welding portion, which at the same time is used as a reaction or. melting pot and is connected with the mold and / or energy joint to the casting mold, thus avoiding the formation of a specially designed and cost-effective pot as well as a special holder for it.

The welding portion can be packed in a bag or in a dose and transported in a pot, after which the welding portion is ignited or melted. incineration of packaging.

Preferably, a reaction crucible is used, characterized in that it has a height of 200 to 800 mm, the wall thickness of the coated liner of the crucible and the bottom of the crucible is 5 to 60 mm and its diameter is 100 to 1000 mm.

Suitably, the opening in the flat floors of 5 pots is 5 to 40 mm large and is closed by a pot stopper which, when in contact with a liquid, hot, aluminothermic reaction mixture, melts and allows the liquid reaction mixture to flow into a foundry mold which is located below it.

The present invention will be explained in more detail below with reference to the accompanying drawing, which shows in Figure 1 the reaction pot of the present invention.

The reaction vessel shown is made of a cylindrical sheath 1 of a metal sheet, e.g. made of white sheet metal fitted with a support handle 2 and a lid 3. In the cylindrical jacket 1 of the pot, push or engage the actual reaction vessel in the form of a sandblast 4 lining, and in the central opening 3 at the bottom of the cylindrical sheath 1 of the pot and the liner 4 instead of a pot for a pot. A welding portion is introduced into the liner of the cylindrical jacket of the pot, either in a commercially available can, or in a regular plastic bag or in other packaging, so that the welding portion fills about 3/4 of the reaction pot.

After planting the reaction pot on the foundry mold and the design and / or energetically joint connection of the reaction pot to the casting mold, e.g. Using the locking edge on the casting mold, remove the lid 3 and ignite the welding portion with the help of a special incendiary stick, after which the lid is replaced.

As soon as the reaction takes place, the sealing material in the opening at the bottom of the reaction pot melts and the liquid melt of steel flows into a mold. In practice, it has been shown that due to the cylindrical shape and the flat bottom of the reaction pot, the welding portion reacts particularly well.

Upon completion of the welding operation, the jacket 1 of the pot can conveniently take over any waste generated during the welding operation, such as mold residues, slag, etc., which facilitates their ecological disposal.

The present invention allows us to proceed with significantly lower requirements and expenditures in respect of equipment, its weight and personnel than before.

It goes without saying that it is possible to adjust the size of the casings to suit the welding requirements.

Claims (3)

PATENT APPLICATIONS Claims 1. A reaction vessel for an aluminothermal rail rolling device, characterized in that it is formed of a cylindrical sheath (1) of a metal sheet, which is provided internally with a refractory liner (4), and is provided with a central bottom in the pot. an opening (5) provided with a sealing material to provide a lid (1) of the pot with a lid (3) and a carrying handle (2) and at the same time form a transport container for a welding portion that can be directly planted on the casting mold and, if necessary also attach it. 2. The reaction pot according to claim 1, characterized in that it has a height of 200 to 800 mm, that the thickness of the wall of the liner and the bottom of the pot is 5 to 60 mm and its diameter is 100 to 1000 mm. Reaction pot according to claims 1 and 2, characterized in that the bottom of the pot has an opening of 5 to 40 mm.