CS276853B6 - The method of welding the strip coils from the media and brass. - Google Patents

Abstract

A method of welding coils of copper and brass strips by arc welding in a protective atmosphere with a non-consumable electrode, without filler material, consisting in the synchronous action of heat from two electric arcs from two opposing welding torches, which in the case of copper or brass with a zinc content of up to 10% are positioned opposite a common axis, or in the case of brass with a zinc content of over 10%, both welding torches are mutually displaced in the direction of the welding edges by 0.1 to 35 mm, while in the case of a pulsating electric welding current the frequency on both welding torches is the same, and in the case of welding torches positioned opposite each other in a common axis the frequencies of both welding currents have a mutual phase shift of 180°.

Description

1 CS 276853 B6

Welding method for strip and strip bands

Technical field

BACKGROUND OF THE INVENTION The present invention relates to a method for welding coils of strips from a medium and a cement, in particular for the formation of transport weld seams or weld seams intended for further processing. by rolling, namely materials with high thermal conductivity, and materials comprising elements with ease of evaporation, based on the synchronous operation of the introduced heat of two opposing electric arcs, two separate, same relative speed welding torches.

The better state of the art

Until now, metallic materials have been welded in the following ways: two-way burners, but the common axis of the welding nozzles has a horizontal direction. It was usually welded from bottom to top. In the case of horizontally oriented weld edges, the welding torch position was similar to that of the previous case. Another known method was based on a horizontally horizontal line of weld edges using a single welding torch, essential in a top-down position, on a support, with a through-through. In the case of two burners in succession, at the top down, the first burner had a weld preheating function.

Neither of these methods of welding has guaranteed the formation of welded joints of the quality required by the modern cold rolling of rolling, high rolling speeds. The most common drawbacks were the occurrence of notches in the head-shaped bead and the elevation above the base material of the bead in the root.

SUMMARY OF THE INVENTION

The above-mentioned drawbacks are largely eliminated by the method of welding the coils of strips of medium and brass oriented to a horizontal position with weld edges in a horizontal plane.

The method according to the invention makes it possible to produce high-quality welded joints, without indentations in the head part of the weld bead, without seams and in the root section, with the required mechanical properties and advantageous economic conditions, the shape, geometry and overall cross-section not exceeding the surface-welded strips, and significantly reduces the occurrence of technological errors, especially with notch effects.

In order to achieve satisfactory results, it is necessary that the sleeve welds synchronously, by the heat of the two electric rounds, the upper and lower welding torches, placed against the nozzle. In the case of a weld of brass or copper containing up to 10% zinc, the welding torches are placed in a common position, and in the case of brass with a content of more than 10% zinc, the welding torches are displaced in the direction of the weld edges by 0 , 1 to 35 mm. At the same time, in the case of a pulsating electric welding current, the frequency on both welding torches is the same, and in the case of welding torches in the common axis, the frequency of the welding currents has a phase shift of 180 °. An embodiment of the invention

The method of welding coils of strips from the media and brass was tested and determined on materials containing 99.9% medium, otherwise 99.5% medium. In addition, the conditions of cleavage on 90% media and 10% zinc as well as 96% medium and 4% zinc were tested and determined. And also materials containing 80% medium and 20% zinc, further containing 70% medium and 30% zinc, as well as 63% medium and 37% zinc. Welding with two welding torches opposite, with the main nozzle axis in vertical orientation, one welding torch above, the other welding torch under the weld, with a synchronous heat input from the two electric arcs, confirmed that in the case of both media and brass up to 10 % zinc reached the highest quality welded joints, provided that the welding torch sleeves for the shielding gas, without melting electrode, were positioned exactly opposite each other. In the case of materials with a content of more than 10% zinc, it has been shown that the mouths of the welding torches have to be shifted by 4 mm, respectively. in another case by 22 mm.

In all cases, the effects of the continuous or pulsating electric current were tested. In the case of a pulsating electric current, both the autonomously welding torches were connected to the synchronized welding current sources with the same frequency, and the influence of the mutual phase shift of the frequency of 180 ° was tested in the case of the welding torches being positioned exactly opposite one another. As a result, the flame inclinations of the welding torches were also tested, as well as the same power of the transferred heat-electric arcs of the two welding torches as well as the welding speed increase during welding.

Welded joints had very good rolling properties, tightness and mechanical strength even after firming. The welded joints remained round to a rolling edge of 0.2 mm. The mechanical refinement of the welded joints was no longer required.

The tests showed that the occurrence of notches in the head part of the caterpillar, respectively. its disproportionate overloading and canting of the weld joint above the base material of the weld in the root portion has been completely eliminated. The occurrence of technological errors, notably with notched effects, was significantly reduced.

Industrial Usability

The method of welding the strip coils from the media and brass can be used in particular when rolling these materials, connecting the strip for rolling at high speed, as well as for the need for static-welded joints, even in conventional workshop sheet production and the like.

Claims (2)

PATENT CLAIMS 1. A method of welding coils of strips of copper and brass, 0.5 to 5 mm thick, by arc welding in a protective atmosphere with a non-melting electrode, without additional material, a continuous or pulsating electric current, characterized in that the weld is applied synchronously, by the heat input of the electric arcs of the upper and lower welding torches, placed with the nozzles facing each other, while in the case of copper or brass welds containing up to 10% zinc the welding torches are placed in a common axis facing each other, and in the case of brass containing more than 10% zinc welding torches relative to each other in the direction of the weld edges, shifted in the range from 0.1 to 35 mm. 2. The method according to item 1, characterized in that in the case of a pulsating electric welding current the frequency on both welding torches is the same, and in the case of welding torches placed in a common axis opposite each other the frequencies of the two welding currents have a mutual phase shift of 180 °.