SU821096A1 - Burner for gas-shield arc welding - Google Patents

Description

(54) ARC WELDING BURNER IN A MEDIA OF PROTECTIVE GASES

The disadvantages of the known device are relatively low depth of penetration with increased protective gas spreading / practically fresh spraying of the internal nozzle and the resulting sharp decrease in efficiency due to the need to clean the internal nozzle from minute to minute from splashes of molten metal.

The closest to the technical essence and the achieved effect to the invention is a torch for arc welding in a protective gas environment, containing a nozzle with a current-carrying mouthpiece located in it with a channel for guiding the electrode, made at the outlet with a cavity, the cross-sectional area of which is larger than the channel section area at the inlet and gas supply 5.

The disadvantage of this torch is the insufficient penetration depth and splashing of the nozzle during the welding process, which does not allow to significantly increase the productivity of the welding process.

The aim of the invention is to increase labor productivity by reducing the degree of splashing of the nozzle and increasing the depth of penetration without increasing the thermal power of the arc.

This is achieved by the fact that in a torch for arc welding in a protective gas environment, there is a nozzle with a current lead mouthpiece located in it with a channel for guiding the electrode made at the outlet with a cavity whose cross-sectional area is larger than the channel cross-sectional area at the inlet and gas supply, the mouthpiece is made channels connecting the gas supply to the cavity.

Thanks to the proposed technical solution, the protective gas flowing into the exit part of the hole in the mouthpiece, under high pressure and at high speed, evenly flows around the electrode from all sides and, falling into the weld pool, injects liquid metal from the end of the electrode, contributing to the deepening of the arc into the metal to be welded . At the same time, the depth of penetration increases by 2-3 or more, and the width of the seam decreases accordingly.

The drawing shows the burner, a longitudinal section.

The burner includes a current-carrying mouthpiece 1, insulated from the gas supply nozzle 2 by an electrical insulating sleeve 3, a melting electrode 4 guided by the coil 5, and a gas supply gas for supplying protective gas. At the outlet of the mouthpiece 1 there is a cavity 7, the cross-sectional area of which is larger than the cross-sectional area of the channel at the inlet. The mouthpiece has channels 8 connecting the gas supply to the cavity 7. The arrow 9 shows the protective gas supplied to the burner. Arrows 10 show part of the protective gas entering the nozzle 2 through the holes in the gas supply b / - these holes have a cross-sectional area S. Arrows 11 indicate the part of the protective gas entering the cavity of the mouthpiece 7 through the channels 8 connecting the gas supply to the cavity 7. Area sections of channels 8 are designated through 52- Position 12 is designated a welded detail.

The burner works as follows.

In gas supply b serves under the pressure of protective gas 9, which through the channels S enters the nozzle 2 and, flowing out of it, protects the weld. Most of the protective gas enters the channels $, from which the gas Q falls into the cavity 7 of the mouthpiece 1 and then flows out of it with great speed. When the arc is excited between the electrode 4 and the part 12 to be welded, a liquid metal is formed, which

g is blown from under the arc by the flow of protective gas 11, which simultaneously deepens the arc and thereby contributes to an increase in the depth of penetration.

Q The best effect is obtained when the ratio of the sections is 1/3 - 1/6 and when the ratio of the areas of the cross section of the inlet of the channel and the area of the cross section of the cavity is 7 1 / 1.05-1 / 1.2. So,

c for example to increase the depth

melting up to 8 mm when welding in carbon dioxide in the lower position of steel sheets with a thickness of 14-16 mm with a welding current of 200-220 A is sufficient to supply to the output part

0 holes in the mouthpiece up to 24-48 l / min of carbon dioxide, at the same time it is enough to feed only 8-12 l / min to the protective gas nozzle. The increase in the depth of penetration occurs5 The more intensive the speed, flowing out of the protective gas mouthpiece, is the more intensive it is. At the same time, in order not to greatly increase the protective gas flow rate, the cross section of the channels 5 and $ 2 are chosen such that, at the established pressure, the total protective gas flow does not exceed 32-60 l / min. Based on these considerations, the ratio of the cross-sectional area of the channel inlet and

With cavity 7 in the mouthpiece 1 is chosen to be approximately 1 / 1,05-1 / 1,2. The supply of shielding gas through the mouthpiece to deepen the arc can be carried out through channels directed along the electrode and touching it or at some distance from it, however, in this case, the outlet holes rapidly splash and the penetration depth decreases.

The supply of part of the protective gas intended for deepening the arc with

Claims (1)

Claim . A torch for arc welding in a medium of 25 protective gases, containing a nozzle with a current-conducting mouthpiece located in it with a channel for guiding the electrode, made at the outlet with a cavity, the cross-sectional area of which is larger than the cross-sectional area of the channel at the inlet, and also a gas supply, characterized in that , in order to increase labor productivity by reducing the degree of splashing of the nozzle and increasing the penetration depth without increasing the thermal power of the arc, channels are made in the mouthpiece connecting the gas supply to the Tew. I