SU1353594A1 - Method and apparatus for automatic submerged overhead arc welding - Google Patents

Abstract

1. A method of automatic submerged-arc welding in the overhead position, in which the flux and electrode are supplied from the bottom of the welded joint with pressure control of the flux, and the maximum pressure section is located behind the arc, characterized in that, in order to improve the quality of the welding, the maximum pressure section of the flux is located at a distance equal to the length of the weld pool. 2. A device for automatic submerged-arc welding in the overhead position, comprising a housing for a flux with an outlet, a welding nozzle placed inside it and an inclined forming lining, which is different in that in order to improve the quality of welding by creating a predetermined pressure on various the formation of the weld pool, the forming gasket is made L-shaped, with the angle of inclination of the area a located near the welding nozzle, and the angle of inclination of the other section of the lining in to the plane you The body orifice of the body is related by ratios, and the lengths of the indicated areas of the lining are chosen according to the ratio i (L 1.5. H, 4. 00 ate co-ed

Description

11353594

This invention relates to automatic submerged-arc welding in the overhead position.

A known method of automatic submerged-arc welding in the overhead position, in which the flux and the electrode are fed from the bottom of the welded joint with pressure control of the flux, and a section of maximum pressure is placed behind the arc,

The disadvantage of this method is that the area of maximum pressure is located at a distance greater than the length of the welding wave, which leads to disruption of the welding process, since the weld metal depresses the forming device.

A device for automatic submerged-flux welding in a ceiling position is known, comprising a housing for a flux with an outlet, a welded junction box located inside it, and forming a lining.

The drawback of the device is that the vertical coaxial arrangement of the screw and the welding die for feeding the electrode wire leads to the same magnitude of the flux pressure before the arc, in the arc area and after it, and this does not contribute to obtaining high-quality ceiling joints in a wide range of technological modes (as with welding in the lower polishing zone), since in this case the distribution of the flux pressure value is required, during the welding process in different parts of the formation of the weld pool

The purpose of the invention is to improve the quality of welding by creating a predetermined pressure in various parts of the formation of the weld pool.

This goal is achieved in that, according to the method of automatic submerged-arc welding in the overhead position, in which the flux electrode is fed from the bottom of the welded joint with pressure control of the flux, and the maximum pressure participants are positioned behind the arc, the maximum pressure portion of the flux is located .

At the same time, in the device for automatic welding under the overhead position, comprising a housing for a flux with an outlet, a welding core is placed inside it

pieces and a tilted forming lining, the forming lining is made L-shaped, while the angle of inclination of the section-o located near the welding nozzle and the angle of inclination of the other section of the lining in to the density of the body outlet orifice are related by the ratio (. 13, 1 ° i 5 5 °, with the lengths of these areas of the lining selected according to

.5a, ".

to the ratio

Fig, 1 shows the device, a general view; figure 2 - section aa in figure 1.

The device comprises a housing 1 in which a welding nozzle 2 is placed and a forming lining 3 is made of G-shaped form. Plot a ployd

ki, located near the mouthpiece.

inclined at an angle to the plane of the outlet of the housing. And another part of the lining is inclined at an angle ft to the plane of the outlet of the housing. In this case, a variable gap is created between the product 4 and the forming pad 3, and a smaller gap c is formed at a distance equal to the liquid

welding bath from the forming device (crater) in the direction from the arc formed by the mouthpiece 2. Moreover, sections a and 5 of the lining 3 are chosen in accordance with the ratio

-, 5.4

and the angles ot and | 1 in this case should satisfy the expressions m:,.

During the welding process, the flux is wedged and wedged in a variable gap, providing it with the necessary pressure in the formation areas of the weld pool.

Before the arc and in the area of the arc, the pressure of the flux must be large, it contributes to the accelerated growth of the molten flux during welding and the formation of slag crust 5,

High pressure is created by selecting the amount of flux fed to the housing 1 and the distance between its upper surface of the product to be welded 4 and the height of the flux cushion.

Beyond the arc within the crater, the pressure of the flux is required not less than in the area of the arc, taking into account

quantities of flux that melt and bake into a crust. This is achieved by creating conditions for jamming the flux in a decreasing gap in the direction from the arc between the forming device and the bottom surface of the joint to be welded, forming an angle of 0. The length of such a section is chosen to be equal to the length of the crater, and it depends on the welding mode, the properties of the material being welded, as well as its geometric dimensions.

In the area after the crater, the pressure of the flux should slowly fall, while ensuring the required maintenance of the crystallizing weld metal with a crust of partially melted flux. This is achieved by gradually spreading the flux in an increasing direction towards the gap formed by the seam between the forming device and the bottom surface of the product, forming an angle and. The length of such a section is chosen depending on the length of the section and with selected parameters of the welding mode, the material and the geometric dimensions of the product.

At the same time, in order to create the required high pressure of the flux in the casing with its economical consumption, the height of the flux cushion sets the minimum value of the maximum allowable edge of the assembled welding parts, which is achieved mainly by selecting the amount of flux supplied to the casing and the installation position of casing 1 for the flux determined in such a way that the ratio between the distance 1 and the diameter D of the outlet opening satisfies the inequality

f, 5.

All this is true for automatic submerged-arc welding in the overhead position in modes similar to those for submerged-arc welding with the difference that the current density A / mm should be about 2-3 times greater (the greater the current density, the greater arc pressure and the greater the depth of melting).

Stabilization of predetermined flux pressures at various sites of formation

five

0

five

0

five

0

five

0

five

The welding bath, taking into account the deviations of the assembly parameters along the length of the joint, ensures, due to the presence of a sufficient excess of flux - - - sa fed into the body, which spills over its entire perimeter through the gap between the body and the product, equal to the height of the flux cushion; smoothly copying the bottom surface of the product with the upper surface of the body; sufficient height of the flux cushion, the value of which is equal to the maximum excess of the edges, which excludes pressing the case by the edge of the product during the welding process (if there are more edges).

An experimental production check of the proposed device showed high reliability and stability of the quality of welded joints with a good formation of welds, which little depends on the unevenness of the gap and exceeding the edges along the joint of the product to be welded.

Welding is performed with or without grooving the edges of the product, both with and without gap, and welding with filler wire into the arc zone is also possible.

To form the upper part of the seam, the electrode can be supplied both from the lower side through the gap between the edges of the product, and from above by any limestone method, thus forming a bed.

The method is used for welding longitudinal and circumferential welds.

The use of the proposed method and device for automatic submerged-arc welding in the ceiling position provides in comparison with the known methods and devices the following advantages: the ability to improve the quality of welded joints and improve the formation of welds as a whole; productivity is not inferior to welding in the lower position; possibility of reliable adjustment of the size. ditch, shape and location of the seam during the welding process; expanding the range of technological regimes and thicknesses of welded products.

In addition, the proposed device is of great practical importance in enhancing the production culture, and in the first place, improving the conditions for performing welding operations that meet the requirements of occupational health and safety.

FIG.

Editor V.Danko

Compiled by V.Rumntsov Tehred L.Oliynyk

Order 5659/14 Circulation 970.Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

2

Proofreader N.Korol

Claims (2)

1. The method of automatic submerged arc welding in the ceiling position, in which the flux and electrode are supplied from the bottom of the welded joint with the regulation of the flux pressure, and the maximum pressure section is located behind the arc, characterized in that, in order to improve the quality of welding, the maximum flux pressure section is placed on a distance equal to the length of the weld pool. 2. A device for automatic submerged-arc welding in the ceiling position, comprising a housing for the flux with an outlet, a welding nozzle placed inside it and an inclined forming lining, which is different in order to increase the quality of welding by creating a given pressure on various sections of the formation of the weld pool, the forming gasket is L-shaped, with the angle «of the inclination of the section a located near the welding mouthpiece and the angle of the other section of the lining in to the exit plane holes in the housing are connected by the relations 3 ° ^ έ13 °; 1% ρέ5 °, and the lengths of these sections of the lining are selected according to 1,5έ-έ4. and squeezes the automatic