SU1324796A1 - Apparatus for protecting butt resistance welding machines from sparks and splashes of melt metal - Google Patents

Abstract

The invention relates to equipment for resistance flash butt welding and can be used to protect current-carrying, moving, and other hours. Crg ;. 54; l -.; ,,. -: t t those machines from sparks and splashes of molten metal. The device allows to increase the productivity of welding machines by improving the conditions of their operation. The device is made in the form of a curved spark-proof shield I (U), mounted by element 2 with the possibility of angular rotation at a small angle. The device is mounted with a convex side toward the current-carrying clamps 4 and 5 of the welding machine and takes on the flow of sparks and splashes of molten metal during melting. At the same time, W 1 is heated and elongated, bulging. When cooling W 1 during the breaks between welds, it shrinks and takes on its original shape. The crust 10 of the cooled metal splashes spontaneously peel off from W. If necessary to protect parts of a round shape (for example, a welding transformer), the spark-proof W 1 is made in the form of sections and, accordingly, are placed around the circumference. 1 hp f-ly, 4 ill. SA :) Gche 4 with 05

Description

The invention relates to equipment for resistance flash butt welding and can be used in various types of welding machines, on which welding is performed by the method of melting, to protect current-carrying, moving and other machine parts from sparks and splashes of molten metal.

The purpose of the invention is to improve the performance of contact butts

They are improved by the conditions of their maximum ratio between the operation. The concave surface of the shield and the tightening of FIG. 1 shows a device for a h element to the width of this element stitched butt welding machine from that (Fig. 1), equal to 0.01-0.05. With sparks and molten metal splashes with a ratio of less than 0.01, deterioration is achieved by the hard joint (a) and from the hinge of the peeling of the crust formed. Compound (b); in fig. 2 --- device 5 When the ratio exceeds 0.05, the conditions with the spark shield and the peel peel are good, but the conditions of spatter adhesion, especially along the edge of the shield, deteriorate with the element protecting the welding. , due to the large circle in the welding machine with current carrying surfaces of their surfaces. The optimum ratio of clamps, in which with the help of clamps 2 °, 01-0.05 results in welded parts before welding the fabric of the experiments, (a), in the welding process (b), after welding (c). make a common appearance; in fig. 3 - shield, made of 14 mm thick steel sheet, and flaked from separate sections, general view; The stiffening element with the rigid connection of FIG. 4 shows section A-A in FIG. 3. Inserting the ends of the same steel several Devices to protect the contact 25 to a greater thickness of 2-6 mm, for high-resistance welding machines from sparks and splashing stiffness. Large thicknesses are chosen when welding large sections. In this case, the ratio h: t increases from 0.01 to 0.05 as the thickness increases.

For example, when welding rods of 20 mm, the shield covering the current leads is made of a sheet with a thickness of 1-2 mm, and the clamping element of a sheet of a thickness of 2-3 mm. At the same time we accept 01-0.02. When welding shafts 80 mm inflow you,. They are made of a sheet with a thickness of 2-3 mm, and steel parts to be welded are 8 and 9. In addition, 5 welding elements from a sheet with a thickness of 2 are marked (Fig. 3), separate sections 114 mm. At the same time, 02-0.03.

When welding 1420x20 mm pipes, the shield is made of a sheet with a thickness of 3-4 mm, and the twisting element of a sheet with a thickness of 3-

Before welding or during manufacturing 6 mm. The ratio, 03-0.05. of the laziness of the welding machine, the device is installed; At the hinged connection of the shield and the station, the thickness of

Thus, so that the convex surface of the shield-last practically does not affect the large 1 was directed towards the current of the maximum gap, the feed clamps 4 and 5. If the sparks and splashes developed during the welding process need to be protected, then the shield are from separate sections And and 12 (fig. 3).

The use of this shield design significantly simplifies and reduces the cleaning process of the welding machine from splashes of molten metal. Large spray crusts are easily removed from the protected areas without the use of special tools (chisels, metal brushes, scrapers), which require considerable effort, and small ones are blown away by the flow during the next period between welds and again the air that is fed in between. As a result, between the flap 1 between welding. Net welding time one

the joint is 3 minutes and the preparation time depends on the organization of the work.

The molten metal contains a curved sparkproof shield 1 with a thickness of 1-4 mm, the ends of which are fastened with a tensioning element 2. The device is installed in the area where the welding transformer 3 is protected, for example (Fig. 2). The flap 1 is installed so that its convex surface is directed toward the current-carrying clamps 4 and 5 (Fig. 2), i.e. clamped to the side b and 7

and 12 shield and ring transformer 13. The proposed device operates as follows.

the melted metal, falling on the flap, cools and crystallizes, forming a crust 10 (Fig. 26), and the flap heats and expands. The position of the shield 1 is changed, the dotted line shows its position before welding (Fig. 26).

During the period between welds, the shield is cooled and occupies the original position. In the process of the next welding, the shield is again heated and expanded, and in the next, a crust of 10 crystallized splashes creates a stress state that

leads to peeling of the crust 10 formed (Fig. 2c). In this case, exfoliation occurs spontaneously, without mechanical impact on the crust from the outside. The greatest stress between the crust and the shield during welding of 01420 mm pipes on the K-700 machine is observed after 3-4 welds depending on the number of splashes falling on the shield.

The optimal curvature of the shield will be at

equals an average of 6.25 minutes. Therefore, the duration of one cycle is 9.25 minutes. Thus, the maximum productivity of the welding machine can be on average 6 joints per hour or more. However, at present, the average productivity is 5 joints per hour. At that, 46.5 minutes is spent on welding and preparing pipes for welding, the rest of the time, in terms of 1 hour of work, 13.7 minutes, is spent on welding machines from molten metal splashes. The need for cleaning appears after welding 4 joints. Consequently, the productivity of welding can be increased by reducing the cleaning time of the welding machine.

The invention allows to reduce the time for cleaning the machine in terms of 1 hour of work, to 4.5 minutes. Therefore, 55.5 minutes can be spent on welding and preparation. During this time, taking into account the duration of one cycle, you can weld 6 joints.

The positive effect of the invention is that it improves the thermal protection of the current-leading parts of the machine. This is especially important when protecting current leads from welding transformers from sparks. As a result, transformers do not receive additional heat load from molten metal splashes, which significantly improves the characteristics of the secondary circuit of the machine.

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Claims (2)

1. A device for protection of contact butt welding machines from sparks and splashes of molten metal, which are formed when the welded parts are melted, containing a spark protection shield, characterized in that, in order to increase the performance of contact butt welding machines by improving their operating conditions, the spark is the shield is curved, mounted on a butt welding machine with a convex surface toward the current-carrying clamps of the machine and 5 is provided with a tensioning element, the width of which is equal to the width of the spark protection shield in a curved state, while the edge of the spark protection shield parallel to its generator is connected to the tensioning element with a possibility of rotation at a small angle and the formation of a gap between the concave surface of the spark protection shield and the torque shield element, and the ratio of the maximum gap between the concave surface of a curved spark-proof 5 of the shield and the tightening element to the width of this element is 0.01 ... 0.05. 2. The device according to claim 1, characterized in that the spark-protection curved shield is made in the form of separate sections. 1 FIG.