SU1138272A1 - Device for automatic electric arc welding of butt joints - Google Patents

Abstract

A device for automatic electric arc welding of butt joints, containing a drive carriage with a carriage rotating around its axis, mechanisms for moving the carriage, feeding the electrode wire and its transverse oscillations, each of which is provided with a control unit, a mechanism for correcting the position of the welding wire, as well as for cutting, executed in the form of a control unit, a control unit for adjusting the position of the welding wire, and the transverse oscillations made in the form of a control unit, a mechanism for adjusting the position of the welding wire, and the transverse oscillations made in the form of a control unit, a mechanism for correcting the position of the welding wire, and the transverse oscillations performed in the form of a control unit, a mechanism for adjusting the position of the welding wire, and mounted coaxially with a welding torch, one of which is rigidly connected to it, and the other is rotatable and is provided with a diametrically located and spring-loaded parallel brushes for follower rollers, each of which is made in the form of two truncated cones and fixed rotatably around its axis, the power source of the welding arc and the source control unit, characterized in that, in order to improve the quality of the welded joints by automatically adjusting welding parameters depending on the width of the groove, it is additionally equipped with series-connected angular rotation sensor of the rotary ring, two adders and a block compared and, as well as series-connected oscillation amplitude sensor, i differentiating element and null-oprailoM, the comparison unit has two outputs (one of which is connected to the wire feed mechanism through the control unit of the wire feeder and the other The mechanism of transverse oscillations of the electrode wire is connected to the amplitude sensor for an oscillation, and through the speed control unit it is connected to the movement mechanism of the driving car, while the amplitude sensor of electric oscillations native wire cheN9 1C Res differentiator and zero-body coupled to a source of control the arc power supply.

Description

The invention relates to welding equipment and can be used to equip automatic welding machines for electric arc welding of thick metal into slotted grooves.

A device for automatic arc welding of butt joints with a groove is known, comprising a welding head equipped with copying rollers which are fixed on spring-loaded forks, the rods of which are mounted so that they can move in a vertical plane, and their free ends are interconnected by means of a hinged bar 1.

However, this device automatically supports only the departure of the electrode wire, and there is no regulation of the transverse stroke of the welding head.

A device for automatic arc welding of butt joints with a groove is known, comprising a drive carriage equipped with a guide tube for feeding the electrode wire, a feeding mechanism and a mechanism for adjusting the position of the electrode wire along the width and depth of the joint mounted on the bracket 2.

The disadvantage of the device is a large number of preparatory and adjustment operations during its operation.

A device for automatic arc welding of butt joints is known, in which the mechanism for adjusting the position of the electrode wire relative to the groove is made in the form of guides rigidly mounted on a bracket, on which an additional bracket with followers rollers Z is mounted.

Its disadvantage is the impossibility of adjusting the position of the electrode wire during welding in a narrow or slotted groove, since in this case the groove surfaces are parallel to the pickup rollers and their reliable contact with the groove width does not ensure.

A device for automatic electrode welding of butt joints is known, which contains a mechanism for adjusting the position of the electrode wire relative to the groove, made in the form of guides rigidly mounted on a brace. An additional bracket with a spring-loaded swivel plate is installed on the guides with the possibility of movement, on which parallel rods are mounted with the possibility of rotation around its axis with fixed rollers fixed to them, made in the form of two truncated cones. One of the two parallel rods is spring-loaded and has the ability to move vertically, and the other

installed only with the possibility of rotation. The welding torch is rigidly connected to the brackets and mounted with the possibility of vertical movement relative to

carriage 4.

The disadvantage of the device is that it does not provide for the exact positioning of the electrode wire in the center of the groove during the welding of curved seams in the change of the welding direction.

The closest technical solution to the invention is a device comprising a driving carriage with a carriage rotating around its axis, mechanisms for moving the carriage, feeding the electrode wire and its transverse oscillations, each of which is provided with a control unit, the welding position adjustment mechanism for cutting two rings mounted coaxially with a welding torch, one

of which it is rigidly connected with it, and the other is spring-loaded, installed rotatably around its axis and provided with diametrically located spring-loaded parallel rods for follow rollers, each of which is made in the form of two truncated cones and fixed -power welding arc and source control unit 5.

A disadvantage of the known device is that it does not adjust the welding mode parameters depending on the change in the width of the groove, which greatly affects the quality of the welded joints, especially in the manufacture of critical structures.

The aim of the invention is to improve the quality of welded joints by automatically adjusting the welding parameters depending on the width of the groove.

This goal is achieved by the fact that a device for automatic arc welding of butt joints, comprising a driving carriage with a carriage rotating around its axis, mechanisms for moving the carriage, feeding the electrode

wire and its transverse vibrations, each of which is equipped with a control unit, a mechanism for adjusting the position of the welding torch relative to the groove, made in the form of two rings installed coaxially with the welding torch, one of which is rigidly connected with it, and the other is rotatably fitted with diametrically located spring-loaded parallel rods for follow rollers, each of which is made

in the form of two truncated cones and fixed with the possibility of rotation around its axis, the power source of the welding arc and the source control unit, additionally

provided with a ring-connected angular rotation sensor, two adders and a comparison unit, as well as oscillatory amplitudes connected in series, a differentiating element and a zero-organ, the comparison unit has two outputs, one of which is connected to the feeding mechanism through the control unit of the wire feeding mechanism electrode wire, and the other through the oscillation control unit and the transverse oscillation mechanism of the electrode wire is connected to the oscillation amplitude sensors, and through the control unit speed - with a drive mechanism for moving the carriage, the vibration amplitude sensor electrode wire through the differentiator and zero-body associated with the control of the arc welding power supply unit.

This device automatically adjusts the feed rate of the electrode wire, the amplitude of its transverse. fluctuations, as well as the speed of welding and welding current depending on the width of the groove, which improves the quality of the welded joint.

FIG. 1 shows a device for automatic welding, a general view; in fig. 2 is a mechanism for adjusting the position of the electrode wire with an angular rotation sensor, a general view; in fig. 3 - the same, top view; in fig. 4 - the mechanism of transverse oscillations of the electrode wire with a sensor for changing the amplitude of oscillations, rear view; in fig. 5 is a block diagram of the device.

. The device comprises a driving carriage 1 with a carriage 2 rotating around its axis, on which a welding torch 3, a feed mechanism 4, a transverse oscillation mechanism 5 of the electrode wire 6 and a mechanism 7 for adjusting its position relative to the groove 8, made in the form of two rings installed coaxially with welding torch 3. The support ring 9 is rigidly fixed on the rod 10, which has the ability to move parallel to itself in the holder 11 by the action of the spring 12. The other ring 13 is rotatable, spring-loaded 4, locked on the brace 15, and installed with the possibility of rotation around its axis on the bearing ring 9 and provided with diametrically located spring-loaded springs 16 and 17, parallel brushes 18 and 19 with follower rollers 20 and 21, made of a step-shape with two working surfaces with which they touch the surfaces of the parts 22 to be welded and the cutting 8 under the action of springs 16 and 17. Each step of the follower rollers has a known frustoconical shape. On the support ring 9 is installed, the sensor 23 of the angular rotation made

in the form of a potentiometer. The movable contact 24 of the sensor 23 of the angular rotation is rigidly fixed on the rotary ring 13. The mechanism 5 of the transverse vibrations is provided with a sensor 25 of the amplitude of oscillations, also made in the form of a potentiometer. The slider 26 of potentiometer 25 is connected to the burner 3 and oscillates with it. The output of the angular rotation sensor 23 is connected to the direct input of the first adder 27, the output of which is connected to the direct input of the second adder 28. The output of the adder 28 is connected to the input of the comparator unit 29 having two outputs. The magnitude of the signal at the outputs of the comparison unit is determined by the following expressions.

First exit;

Wow Kivh,

if ubx up.e. shh

and Uftbix Vn.3.-max,

if UBX Vp.5. max (1)

Second exit: Uyv 0,

if UBX - Vn.i.-max

and out. K UKX,

if.vds Vn.j.-tnax-, where VKX - the value of the input signal;

the output value of the output signal; Vn.}. Max-value of the signal setting the maximum wire feed speed; K - block gain factor.

The first output, the signal on which is proportional to the input signal, if the input signal is less than the maximum electrode wire feed speed, is connected to the wire feeder 4 via the feed control unit 30. The second output of the comparator unit 29, the signal on which appears only in the case when the input signal is greater than the signal for setting the maximum wire feed speed, is connected via the oscillator control unit 31 to the transverse oscillation mechanism 5 of the electrode wire 6 and through the control unit 32 speed with movement mechanism 33 driven 1.

The output of the sensor 25 of the amplitude of the transverse oscillations of the electrode wire through the differentiating element 34 and the null organ 35 is connected with the control unit 36 of the power source 37 of the welding arc.

The device works as follows.,

Before the start of welding, in the first adder 27 a predetermined angle of rotation o is established (from the rotary ring 13, corresponding to the predetermined cutting width of the welded joint, in the second adder 28 - the prescribed feed speed U.aad, and in the comparison unit 29 the maximum feed rate of the electrode wire Vn is set. irriax In the welding speed control unit 32, the specified welding speed is set, and in the control unit 36, the power source is controlled by the voltage on the Uce arc, the current per pulse I cc and its duration t min. Then the followers rollers 20 and 21 me The external force corrections are compressed and inserted into the groove 8 prior to contact with its walls. Under the action of the spring 12, the followers rollers 20 and 21 are pressed against the outer surfaces of the welded parts 22. At the same time, the welding torch 3 and, accordingly, the electrode wire 6 occupy a position in the middle of the groove. After the start of welding, the rollers 20 and 21 move together with the welding torch 3 along the groove. If the groove width and the corresponding angle of rotation of the rotary ring 13 are equal to the specified one, then there is no signal at the output of the first adder 27 m and welding conditions, the rate of wire feed speed, welding arc voltage, are given. No welding current pulses. When reducing the width of the groove 8, the following rollers 20 and 21 under the action of the spring 14 change the position, constantly touching the groove walls, cause the rotary ring 13 to mix around its axis and correspondingly reduce the output signal of the rotary ring angle sensor 23. The signal-at the output of the first adder 27 becomes negative and will be more in absolute value, the greater the decrease in cutting. As a consequence, it also decreases. the output of the second adder 28 and the signal at the first output 29. Compare that through the feed control unit 30 reduces the number of rotations of the feeder for feeding the electrode wire 4, i.e., when the width of the groove decreases, the supply of electrode wire and welding current are reduced. As the width of the groove 8 increases, the rotary ring 13 rotates clockwise, the output signal of the rotary ring rotation sensor 23 increases. Accordingly, the signal at the outputs of the first 27 and second 28 adders, as well as the first output of the comparator unit 29, also increases, which leads to an increase in the feed rate of the electrode wire and an increase in the welding current, thereby compensating for an increase in cutting. However, the feed rate of the electrode wire cannot increase above any particular value determined by the material of the welded joint. When exceeding the specified maximum feed rate of ush-ahhv welded joint defects may form in the form of cracks. To avoid this, a signal for the maximum supply of electrode wire is introduced into the comparator block 29. With a further increase in the width of groove 8, the signal from the second adder 28 can reach and even exceed Vn.vrtay. In this case, the signal at the first output of comparator 29 according to the formula (1) will set Vn-smex and stop increasing, but will turn on and increase accordingly an increase in the width of the groove signal at the second output of the comparator unit 29 according to formula (2). This signal is fed to the inverted input of the welding speed control unit 32. Due to the fact that this signal increased as the width of the groove increased, the welding speed would decrease. The signal from the second output of the comparator unit 29 is also fed to the input of the control unit 31 of the transverse oscillation mechanism of the electrode wire, and the larger this signal (the larger the cutting width), the greater the amplitude of oscillation of the mechanism 5. The amplitude of the transverse oscillations of the electrode wire is measured by sensor 25. The signal from this sensor, differentiated by the differentiating link 34, goes to the null organ 35. When the derivative signal of the 25 gauge 25 gauge 25 is equal to zero, the signal to the control unit 36 of the power source 37 is output. . In the generation of the signal from the nullorgan 35, the control unit 36, via the power source 37, outputs a pulse of welding current with predetermined amplitude and duration parameters tnnn. Welding current pulses are needed for a better fusion of the weld metal with the edges of cutting with increasing its width. In the proposed device, depending on the width of the weld joint, the welding mode parameters are automatically set; wire feed speed, welding speed, the amplitude of the transverse oscillations of the electrode wire and welding current, the technical and economic efficiency of the proposed device is to improve the quality of welded joints by increasing the tracking accuracy along the width of straight and curved seams, to increase labor productivity due to reduce the amount of weld metal and save welding materials.

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FIG. five

Claims (1)

DEVICE FOR AUTOMATIC ELECTRIC ARC WELDING OF BUTT JOINTS, containing a drive trolley with a carriage rotating around its axis, mechanisms for moving the trolley, feeding the electrode wire and its lateral vibrations, each of which is equipped with a control unit, a mechanism for adjusting the position of the welding torch relative to the cutting, made in the form of two rings , 'mounted coaxially with the welding torch, one of which is rigidly connected to it, and the other - With the possibility of rotation and equipped with diametrically located spring-loaded parallel rods for tracking rollers, each of which is made in the form of two truncated cones and fixed with the possibility of rotation around its axis, the power source of the welding arc and the source control unit, characterized in that, in order to improve the quality of welded joints by automatically adjusting the welding parameters depending on the width of the groove, it is additionally equipped with a series-connected sensor for the angular rotation of the rotary ring, two adders and a comparison unit, as well as e connected in series with an oscillation amplitude sensor, _{about a} differentiating link and zero orgay, SS and the comparison unit has two outputs, one of which is connected to the electrode wire feed mechanism through the wire feeder control unit, and the other through the oscillation control unit and the electrode transverse vibration mechanism the wire is connected to the oscillation amplitude sensor, and through the speed control unit, to the drive carriage movement mechanism, while the electrode vibration amplitude sensor through a differentiating link and a null organ is connected to the control unit of the welding arc power source. SU,., 1138272