WO2015064125A1

WO2015064125A1 - Welding apparatus

Info

Publication number: WO2015064125A1
Application number: PCT/JP2014/060730
Authority: WO
Inventors: 清出津野; 智太田; 良輝戸舘; 雅敏皆原
Original assignee: 小池酸素工業株式会社
Priority date: 2013-10-28
Filing date: 2014-04-15
Publication date: 2015-05-07
Also published as: JPWO2015064125A1; JP6113858B2

Abstract

The present invention addresses the problem of providing a welding apparatus for welding a flange (2), which is a member to be welded, to a cylindrical pipe (1), there being no increase in the size of the apparatus even when the diameter of the cylindrical pipe is enlarged. A welding apparatus has: a rotation-drive device (turning roll (A)) on which a cylindrical pipe (1) and a flange (2), which is a member to be welded, are placed and caused to rotate; a rotation control unit for controlling the rotation of a rotation drive member; and a carriage (B) on which is mounted a welding torch (20) for welding the cylindrical pipe (1) and the flange (2), and which is placed so as to be able to travel around the cylindrical pipe (1); the carriage (B) being provided with an incline detection instrument for detecting the incline of the carriage (B) toward the travel direction. The apparatus has a controller for generating an instruction signal for accelerating or decelerating the rotation drive member in relation to the rotation control unit of the rotation drive device in accordance with the detected direction of the incline when the incline of the carriage (B) toward the travel direction has been detected.

Description

Welding equipment

According to the present invention, a carriage mounted with a welding torch is mounted on an outer peripheral surface of a cylindrical tube that is arranged in a horizontal direction or set at a desired angle and travels simultaneously. The present invention relates to a welding apparatus capable of welding a member to be welded.

Steel pipes, stainless steel pipes, aluminum pipes and other cylindrical pipes are butt welded, or welded members such as flanges and end plates are welded to the cylindrical pipes. Such a welding operation is performed using a welding torch such as a plasma welding torch, a carbon dioxide gas welding torch or an argon gas welding torch depending on conditions including the material of the cylindrical tube. Such welding torches are either hand-operated by an operator or automatically operated by being mounted on a mechanical device, depending on conditions such as the diameter of the cylindrical tube and the dimensions and shape of the member to be welded. Selected.

When welding a material to be welded to each other or between cylindrical tubes, the cylindrical tube and the material to be welded may be arranged in a horizontal direction and placed on a turning roll and welded while rotating both at the same speed. In this case, a cantilever-shaped arm is provided on a stand installed in the vicinity of the turning roll, and a welding device in which a welding torch is arranged at the tip of the arm is used to control the rotation of the turning roll. A welding apparatus configured so that the peripheral speed can be set to a target welding speed is used. In this welding apparatus, the welding torch can be positioned at the highest point of the cylindrical tube arranged in the horizontal direction, and downward welding can be performed in a stable posture on the cylindrical tube.

Further, an inner surface welding apparatus described in Patent Document 1 has been proposed as an apparatus for welding the inner surface of a cylindrical tube placed on a turning roll. This inner surface welding apparatus is provided with a welding machine at the tip of the telescopic beam that enters the inside of the cylindrical tube, and allows the torch constituting the welding machine to enter the inside of the cylindrical tube to perform downward welding. .

Furthermore, a positioner is also used in which a cylindrical tube and a material to be welded are attached to a rotary table, set to a desired angle, and a target welding site is welded while rotating the rotary table. This positioner performs welding manually while rotating the rotary table after setting the rotary table to which the worker attaches the cylindrical tube and the material to be welded at an angle at which the worker can work most easily.

Japanese Patent Laid-Open No. 10-249520

In a welding device equipped with an arm equipped with a welding torch on a stand installed in the vicinity of the turning roll, it is necessary to increase the height of the stand and the length of the arm as the diameter of the cylindrical tube increases. There is a problem of doing. In addition, since the arm is configured in a cantilever shape, the arm is easily affected by vibration, and the welding torch may be shaken by vibration and affect the welding quality.

In the inner surface welding apparatus disclosed in Patent Document 1, stable inner surface welding can be performed without being greatly affected by a change in diameter when the inner surface of the cylindrical tube is welded. However, when this welding device is used to weld the outer peripheral surface of the cylindrical tube, problems such as an increase in size of the device and the influence of vibration remain as in the case described above.

Furthermore, when a large-diameter cylindrical tube is attached to the rotary table of the positioner and welded, a stand equipped with a welding torch is installed in the vicinity of the positioner, so that the same problem as described above occurs.

An object of the present invention is to provide a welding apparatus that does not increase in size even when the diameter of a cylindrical tube increases.

In order to solve the above-mentioned problems, a welding apparatus according to the present invention is a welding apparatus for welding a member to be welded to a cylindrical tube, and rotates by placing and rotating the cylindrical tube and the member to be welded to the cylindrical tube. A drive device, a rotation control unit for controlling the rotation of the rotation drive device, and a welding torch for welding the cylindrical tube and the member to be welded are mounted, and can travel on the outer periphery of the cylindrical tube placed on the rotation drive device. A trolley mounted on the trolley, and the trolley is provided with a tilt detector that detects the tilt of the trolley in the traveling direction. When the tilt detector detects the tilt of the trolley, And a control device that generates an instruction signal for accelerating or decelerating the rotation driving device to the rotation control unit of the rotation driving device in accordance with the direction of inclination.

In the above welding apparatus, the control device compares the welding current at the start of welding with the current welding current, and detects that the current welding current is larger than the welding current at the start of welding. At this time, it is preferable that the traveling of the carriage is stopped for the cylindrical tube and the instruction signal for stopping the rotation is generated by the rotation control unit of the rotation drive device, assuming that the welding of the entire circumference is completed.

In any one of the above-described welding apparatuses, the rotation driving device is a turning roll for placing and rotating the cylindrical tube in the horizontal direction, or rotating the placed cylindrical tube at a desired angle. A positioner is preferred.

In the welding apparatus according to the present invention, the welding torch is mounted on a carriage placed on the outer peripheral surface of the cylindrical tube. For this reason, the rotational drive device is controlled so that the circumferential speed of the outer peripheral surface of the cylindrical tube placed on the rotational drive device is equal to the welding speed, and the traveling speed of the carriage is set equal to the welding speed. Thus, by placing on the cylindrical tube so as to run in the opposite direction to the rotational direction of the cylindrical tube, it is possible to perform downward welding along the target welding line.

The outer diameter of a cylindrical tube that can be applied to a carriage equipped with a welding torch is determined by the relationship between the distance between the front and rear wheels and the height from the ground contact surface of the wheel to the bottom of the carriage. For this reason, as the outer diameter of the cylindrical tube increases, it is possible to realize a stable traveling. Accordingly, it is possible to cope with the outer diameter of the cylindrical tube, and the entire apparatus is not enlarged.

If the speed of the outer peripheral surface of the cylindrical tube placed on the rotary drive device and the speed of the carriage do not match, the carriage tilts forward or backward in the traveling direction, but this inclination is an inclination provided on the carriage. It can be detected by a detector. In particular, the carriage is set to a speed equal to the target welding speed, and the reliability with respect to the speed is sufficiently high. For this reason, downward welding can be continued by controlling the rotation of the rotation drive device so that the carriage does not tilt forward or backward based on the detected tilt direction.

Also, the welding current at the start of welding is compared with the current welding current, and when it is detected that the current welding current is larger than the welding current at the start of welding, the welding of the entire circumference is completed. As a result, the operation of the welding apparatus can be stopped. That is, the traveling of the carriage can be stopped and the rotation of the turning roll can be stopped at the same time.

Also, when the rotation drive device is a turning roll that rotates the cylindrical tube placed horizontally, the cylindrical tube having a large diameter can be welded in a stable state.

Further, when the rotation driving device is a positioner that rotates the mounted cylindrical tube at a desired angle, the cylindrical tube can be rotated at a desired angle including horizontal, and this process Can be welded. In particular, when a carriage is placed on the outer periphery of a cylindrical tube inclined at a desired angle, a downward component force acts on the carriage in a direction along the axis of the cylindrical tube. The travel of the cart can be guided.

It is a front view explaining the structure of the welding apparatus which concerns on 1st Example. It is a sectional side view explaining the structure of the welding apparatus which concerns on 1st Example. FIG. 3 is a block diagram of a control system according to the first embodiment. It is a flowchart which controls the welding apparatus which concerns on 1st Example. It is a figure explaining the structure of the welding apparatus which concerns on 2nd Example.

Hereinafter, the welding apparatus according to the present invention will be described. The welding apparatus according to the present invention is configured to include a rotary drive device that mounts and rotates a cylindrical tube, and a travelable carriage equipped with a welding torch. The carriage is placed at the highest position on the outer peripheral surface of the cylindrical tube and travels at the welding speed. At the same time, the outer surface of the cylindrical tube is the same as the traveling speed of the cart and the rotational direction is the traveling of the cart. It is rotated so that it is opposite to the direction.

Therefore, in the welding apparatus according to the present invention, it is possible to perform stable welding on the target welding site by the welding torch mounted downward on the carriage. For this reason, it is advantageous to use when butt-welding the cylindrical tubes placed on the rotary drive device or when welding a plate-like member to be welded including a flange to the cylindrical tube.

In the present invention, the material of the cylindrical tube and the member to be welded is not particularly limited, and a tube or a plate made of steel, stainless steel, or aluminum is an object.

The welding torch is selected according to the material of the cylindrical tube and the member to be welded. Examples of such welding torches include a welding torch for performing carbon dioxide arc welding, a welding torch for performing plasma welding, and a welding torch for performing argon gas welding. In particular, since the welding torch is at the highest position on the outer peripheral surface of the horizontally disposed cylindrical tube, it is necessary to be able to continuously supply welding materials such as welding wires and shielding gas. .

The traveling speed of the carriage is a speed for performing the desired welding, and is set to an optimum speed corresponding to the material and thickness of the cylindrical tube. That is, since the carriage travels with respect to the outer peripheral surface of the cylindrical tube, the relative speed with respect to the portion to be welded is the speed in the downstream direction of welding (hereinafter referred to as “welding speed”, “travel speed of the carriage”). ) And maintained at a constant speed while welding is continued. The cylindrical tube is driven by a rotary drive device and is held so that the speed of the outer peripheral surface in the direction opposite to the traveling direction of the carriage (hereinafter referred to as “peripheral speed of the outer peripheral surface”) matches the welding speed. The For this reason, the traveling speed of the carriage and the circumferential speed of the outer peripheral surface coincide (the traveling speed of the carriage coincides with the speed of the outer peripheral surface, the same applies hereinafter), and the carriage holds the highest position of the cylindrical tube. It is possible to continue welding.

However, the peripheral speed of the outer peripheral surface of the cylindrical tube fluctuates due to various causes, and a speed difference may occur with the traveling speed of the carriage. When the peripheral speed of the cylindrical tube and the traveling speed of the carriage do not match, the carriage moves from the highest position of the cylindrical pipe to the upstream or downstream side in the rotational direction of the cylindrical pipe, and the attitude of the carriage with respect to the horizontal plane tilts backward, or It will tilt forward. As the carriage tilts, the attitude of the welding torch with respect to the cylindrical tube also changes, which may cause a problem that stable downward welding cannot be continued.

For this reason, in the welding apparatus according to the present invention, when the tilt detector is provided on the carriage and the tilt detector detects the tilt in the traveling direction, the rotation is performed so as to correct the tilt according to the detected tilt. The drive device is controlled to be accelerated or decelerated.

Further, the means for causing the carriage placed on the cylindrical tube to travel along the target welded part is not particularly limited, and conventionally employed means can be selectively used. For example, when the target welding site is a butt portion between cylindrical tubes, the butt portion can be detected by a sensor to control the traveling direction of the carriage. In addition, when the target welding site is the corner between the cylindrical tube and the plate-like welded member, the running direction of the cart can be changed by running the cart so that the guide roller is pressed against the plate-like welded member. It is possible to set the direction along the member to be welded.

The rotary drive device is for placing and rotating a cylindrical tube and a member to be welded to the cylindrical tube at the same time, and the posture in which the cylindrical tube is placed is not limited. For example, it may be a turning roll in which a plurality of rolls are spaced apart in a horizontal plane along the axial direction, and a member to be welded and a cylindrical tube are placed on these rolls and rotated. In this turning roll, the outer peripheral surface of the cylindrical tube is supported at two or more places, and the roll is rotated by setting the rotational speed so that the peripheral speed of the outer peripheral surface of the cylindrical tube becomes the target welding speed. It is possible to rotate the welding member and the cylindrical tube.

Also, the rotation drive device may be a positioner having a rotary table that can be set to a desired angle including horizontal. In this positioner, one end of the cylindrical tube is attached to the rotary table together with the member to be welded, and the rotary table whose rotational speed is set so that the peripheral speed of the outer peripheral surface of the attached cylindrical tube becomes the target welding speed is rotated. By doing so, the member to be welded and the cylindrical tube can be rotated.

Hereinafter, the welding apparatus according to the first embodiment will be described with reference to the drawings. The welding apparatus according to this embodiment shown in FIGS. 1 and 2 employs a turning roll A as a rotational drive device. And it is comprised so that the flange 2 which consists of a steel plate as a to-be-welded member can be fillet welded to the edge part of the cylindrical pipe 1 which consists of the steel pipe mounted horizontally with respect to the turning roll A. The flange 2 is placed on the turning roll A in a state where it is temporarily attached to the end of the cylindrical tube 1 in advance.

The turning roll A uses at least two turning rolls A arranged in parallel in order to support and rotate both ends of the cylindrical tube arranged in the horizontal direction in the axial direction. For example, when butt welding cylindrical tubes, two turning rolls A are required for each cylindrical tube. The turning roll A includes a frame 11, a pair of

rolls

12 and 13 arranged so as to be movable along the frame 11, and a control panel 14 incorporating a rotation control unit 30 that controls the rotation of the

rolls

12 and 13. It is configured.

The frame 11 is provided with a rail 11b that guides the movement of the

rolls

12 and 13 at the top of the main body 11a, and a shaft 11c that drives the

rolls

12 and 13 to approach or separate from each other at the side. It has been. A sprocket wheel 11d is attached to the shaft 11c, and the two turning rolls A can be moved simultaneously by aligning two turning rolls A and connecting them with a chain (not shown). Therefore, the interval between the

rolls

12 and 13 can be set in accordance with the diameter of the cylindrical tube 1 to be placed.

The

rolls

12 and 13 are rotatably supported by bearings 12b and 13b attached to

brackets

12a and 13a configured to be movable along the rail 11b of the frame 11. The

brackets

12a and 13a are provided with fixing

screws

12c and 13c. The fixing screws 12c and 13c are configured to be immovable by rotating and fixing the fixing screws 12c and 13c to the main body 11a of the frame 11. .

It is necessary that at least one of the

rolls

12 and 13 is configured as a drive roll. In this embodiment, the roll 12 is configured as a drive roll and the roll 13 is configured as a driven roll. The drive roll 12 is provided on the bracket 12 a and is driven by a drive motor 36 whose rotation is controlled by the rotation control unit 30. Therefore, it is possible to drive the cylindrical tube 1 at a desired peripheral speed by placing the cylindrical tube 1 arranged in the horizontal direction on the drive roll 12 and the driven roll 13 and driving the drive roll 12 by the drive motor 36. It is.

The control panel 14 includes a rotation control unit 30 described later, an operation switch 35 including a speed setting switch for setting the number of rotations of the drive roll 12, a switch for instructing rotation start and stop of the drive motor 36, and the carriage B. A transmission / reception unit 34 and the like for transmitting and receiving signals to and from the provided control device 40 are provided. The arrangement position of the control panel 14 is not particularly limited, and is preferably arranged at an optimum position in consideration of operability and safety.

Next, the configuration of the carriage B will be described. The carriage B is basically composed of a general-purpose welding carriage, and a magnet (not shown) arranged inside the casing 21 is attracted to the cylindrical tube 1 by approaching the bottom surface toward the bottom surface, and is separated from the cylindrical tube 1 by being separated. It is comprised so that adsorption | suction may be cancelled | released and it may detach | leave. Therefore, in a state where the magnet is attracted to the cylindrical tube 1, the cart B does not fall from the cylindrical tube 1 even if the carriage B is inclined forward or backward somewhat.

The carriage B has a plurality of wheels 22 that are driven by a drive motor 48 built in the casing 21, and one side at the upper part of the casing 21 (the flange 2 side in FIG. 1 in this embodiment). A torch holder 23 for holding the welding torch 20 is disposed. In particular, since the welding torch 20 is held by the torch holder 23, both are substantially integrated. In addition, an operation panel 24 provided with an operation switch 45 including a speed setting switch for inputting the traveling speed of the carriage B, a switch for starting the traveling of the carriage B, and the like is disposed on the upper portion of the casing 21.

Further, on both end surfaces of the casing 21 in the traveling direction, arms 25 each having a roller rotatably attached to the tip are disposed. The arm 25 is mounted such that the roller is arranged on the same side as the torch 20 and the protruding dimension of the roller behind the running direction from the casing 21 is larger than the protruding dimension of the front roller from the casing 21. .

When the carriage B travels in the direction of arrow a shown in FIG. 2 (the cylindrical tube 1 is rotated in the direction of arrow b), the rollers B are arranged in contact with the flange 2 so that the carriage B Tilt the running direction toward the flange 2. For this reason, as the carriage B travels, each roller presses against the flange 2 and rotates. As a result, the wheels 22 slip, and as a result, the carriage B surely moves in the direction along the flange 2. It becomes possible to travel.

The casing 21 of the carriage B is provided with an inclination detector 46 for detecting the inclination of the carriage B with respect to the horizontal plane. Whether the carriage B is in a horizontal state or a forward inclination state by the inclination detector 46. It is configured so that a signal can be generated by detecting whether or not the vehicle is tilted backward. The installation position of the inclination detector 46 is not particularly limited, and may be inside the casing 21 or inside the operation panel 24 provided in the casing 21.

The welding torch 20 includes hoses (not shown) including a hose for supplying gas according to the specifications of the welding torch 20, a hose for supplying a welding wire, and a cap tire connected to a welding power source. ), Is connected. The casing 21 is connected to cords (not shown) connected to a power source.

Further, a welding current detector 47 is connected to the welding torch 20 and is configured to be able to detect a welding current while welding the cylindrical tube 1 and the flange 2. When it is detected that the welding current detected by the welding current detector 47 has reached a welding current value that has been set in advance to the first formed weld bead, welding to the cylindrical tube 1 and the flange 2 is performed. Judge as finished.

That is, the value of the welding current changes as the distance between the welding torch 20 and the welded portion changes. For this reason, the welding current may change according to slight irregularities on the surface of the cylindrical tube 1 due to the progress of welding. In particular, when the welding to the cylindrical tube 1 is finished, the welding torch 20 is connected to the initially formed weld bead, and the welding current is abruptly reduced as the distance between the welding torch 20 and the surface of the weld bead becomes extremely small. The welding current value changes. Therefore, it is possible to determine that welding has been completed by measuring a change in the welding current when connecting with the weld bead in advance and setting a threshold value that can detect this change.

In the figure, reference numeral 26 denotes a lever for making the magnet built in the casing 21 approach or separate from the cylindrical tube 1.

Next, the control system of the turning roll A and the carriage B will be described with reference to FIG. In the figure, the rotation control unit 30 is built in the control panel 14, and the control device 40 is disposed at a predetermined position on the carriage B (for example, in the vicinity of the operation panel 24 of the casing 21). The rotation control unit 30 and the control device 40 are configured to be able to transmit and receive signals to each other via wired or wireless.

In the present embodiment, transmission and reception of signals between the rotation control unit 30 that controls the rotation of the turning roll A and the control device 40 that controls the entire welding apparatus including the running of the carriage B and the operation of the welding torch 20 is performed wirelessly. It is configured to perform via.

The rotation control unit 30 has a function of controlling the rotation of the turning roll A (rotation of the drive roll 12). For this reason, the rotation control unit 30 includes a central processing unit having a conversion unit 31d that converts signals to be transmitted to and received from the control device 40 via the comparison calculation unit 31a, the storage unit 31b, the drive control unit 31c, and the transmission / reception unit 34. A part 31 is provided. Further, the rotation control unit 30 is connected to an operation switch 35 including a speed setting switch for inputting the rotation speed of the turning roll A (the rotation speed of the drive roll 12), a switch for rotating or stopping the drive motor 36, and the like. An input unit 32 is provided for transmitting the input operation signal to the central processing unit 31. Further, an output unit 33 that outputs the drive signal output from the central processing unit 31 to the drive motor 36 of the drive roll 12 is provided.

The control device 40 has a function to control including the traveling of the carriage B, the operation of the mounted welding torch 20 and the rotation of the turning roll A. Therefore, the control device 40 includes a central processing unit having a conversion unit 41d that converts signals to be transmitted to and received from the rotation control unit 30 via the comparison operation unit 41a, the storage unit 41b, the drive control unit 41c, and the transmission / reception unit 44. 41 is provided.

In the storage unit 41b, a program from the start to the end of welding by the welding torch 20, the threshold of the tilt angle of the carriage B when controlling the rotation of the turning roll A, welding control according to the change in welding current, A program, data, and the like such as a threshold value for determining that the current value at the time of continuing welding has reached the first weld bead is stored.

Further, the control device 40 includes an operation switch 45 including a speed setting switch for inputting the traveling speed of the carriage B, a switch for rotating or stopping the drive motor 48, a switch for operating or stopping the welding torch 20, and the like. An input unit 42 is provided which is connected to the measuring device 46 and the welding current detector 47 and transmits each input signal to the central processing unit 41. Furthermore, the output part 43 which outputs the drive signal output from the center calculating part 41 to the drive motor 48 of the trolley | bogie B is provided.

The inclination detector 46 detects the inclination of the carriage B in the traveling direction and generates a signal corresponding to the inclination angle and the inclination direction (whether the carriage B is inclined forward or backward). Tell the central processing unit 41. The storage unit 41b of the central processing unit 41 stores in advance the inclination angle of the welding torch 20 that may adversely affect the welding quality of the cylindrical tube 1 and the flange 2, and the comparison operation unit 41a detects the inclination of the carriage B detected. The angle is compared with the inclination angle stored in advance. As a result of comparison, if it is found that the inclination angle of the carriage B detected by the inclination detector 46 is larger than the inclination angle that is a threshold value stored in advance, the inclination angle of the carriage B with respect to the rotation control unit 30 of the turning roll A And a signal corresponding to the tilt direction is transmitted.

For example, when the peripheral speed of the outer peripheral surface of the cylindrical tube 1 is larger than the traveling speed of the carriage B, the carriage B rotates in the direction corresponding to the speed difference between the two along the rotation of the cylindrical pipe 1 (the direction of the arrow b). It will move to the downstream side, and the carriage B tilts backward. The tilt detector 46 detects that the carriage B is tilted backward and the tilt angle, and generates, for example, a + signal corresponding to “back tilt” and a tilt angle signal.

Further, when the peripheral speed of the outer peripheral surface of the cylindrical tube 1 is smaller than the traveling speed of the carriage B, the carriage B rotates in the direction corresponding to the speed difference between the two along with the rotation of the cylindrical pipe 1 (arrow b direction). It will move to the upstream side, and the carriage B tilts forward. The tilt detector 46 detects that the carriage B is tilted forward and the tilt angle, and generates, for example, a − signal corresponding to “forward tilt” and a tilt angle signal.

Therefore, the value of the inclination angle of the welding torch 20 capable of performing stable welding to the cylindrical tube 1 is stored in the storage unit 41b of the central processing unit 41, and the inclination angle detected by the inclination detector 46 is stored. It is possible to determine whether or not the rotation of the cylindrical tube 1 should be controlled by comparing with the comparison calculation unit 41a.

Also, the welding current detector 47 detects the welding current value and transmits it to the central processing unit 41 of the control device 40 while the welding torch 20 is operating. The storage unit 41b of the central processing unit 41 stores the optimum welding current value and allowable variation range corresponding to each welding condition for each welding condition made of the material, thickness, etc. of the cylindrical tube 1. The welding current detected by the welding current detector 47 is compared with the comparison calculation unit 41a. When the value of the detected welding current exceeds the preset allowable fluctuation range, the welding torch 20 has reached the weld bead formed at the start of welding, that is, the target welding to the cylindrical tube 1 has been completed. It is possible to determine.

Next, the flow of work when welding the cylindrical tube 1 and the flange 2 placed in a horizontal direction with respect to the turning roll A will be described with reference to FIG.

First, the cylindrical tube 1 temporarily attached with the flange 2 is placed horizontally and placed on the turning roll A, and the operation switch 35 of the rotation control unit 30 is operated to rotate the rotational speed (peripheral speed of the outer peripheral surface) of the drive roll 12. ).

Further, the operation switch 45 of the control device 40 is operated to input welding conditions including the traveling speed (welding speed) of the carriage B and the allowable inclination angle of the welding torch 20. The carriage B is arranged at the highest position of the cylindrical tube 1 arranged horizontally. Then, the arm 25 attached to both end faces in the traveling direction is adjusted to project from the casing 21, the rollers of each arm 25 are brought into contact with the flange 2, and the lever 26 is operated so that the magnet built in the casing 21 is cylindrical. Approach the tube 1.

Preparation of welding to the cylindrical tube 1 is completed by turning the turning roll A and the carriage B as described above. Thereafter, when the rotation of the drive roll 12 of the turning roll A is started (step S11), the rotation of the cylindrical tube 1 in the arrow b direction by the turning roll A is started (step S12).

A signal generated with the start of rotation of the drive roll 12 is converted by the conversion unit 31d of the central processing unit 31, and is transmitted from the transmission / reception unit 34 of the rotation control unit 30 to the control device 40 via the transmission / reception unit 44 of the control device 40. (Step S13).

The cart that has received the signal that the rotation of the turning roll A has started, starts traveling in the direction of arrow a at a preset speed, and starts the operation of the welding torch 20 in accordance with a preset welding program. (Step S21). Further, the current value when welding is started is measured and stored in the storage unit 41b of the central processing unit 41 (step S22).

When the rotation of the cylindrical tube 1 and the traveling of the carriage B are started, the inclination detector 46 detects the inclination of the carriage B and transmits it to the central processing unit 41 via the input unit 42. In the comparison calculation part 41a of the central calculation part 41, the current inclination of the carriage B transmitted from the inclination detector 46 is compared with the threshold value stored in the storage part 41b, and whether the carriage B is in a horizontal state or the + direction It is determined whether or not the inclination of the inclination exceeds the threshold or the inclination in the negative direction exceeds the threshold (step S23).

If it is determined that the carriage B is in a horizontal state, the current state is maintained without issuing a special control signal (steps S24 and S25).

Further, the welding current detector 47 continues to detect the welding current while the welding torch 20 is operating, and transmits the detected welding current value to the central processing unit 41 via the input unit 42. In the comparison calculation unit 41a of the central calculation unit 41, the current welding current value transmitted from the welding current detector 47 is compared with the threshold value stored in the storage unit 41b, and whether the detected welding current value exceeds the threshold value. It is determined whether or not (step S26).

If it is determined in step S26 that the current welding current value does not exceed the threshold value, the process returns to step S23 and the welding operation is continued. When it is determined that the current welding current value has exceeded the threshold value, a stop signal is output from the drive control unit 41c of the central processing unit 31 to the drive motor 48 of the carriage B, and the traveling of the carriage B is stopped ( Step S27). The stop signal of the carriage B is also transmitted to the rotation control unit 30 of the turning roll A.

When it is determined in step S23 that the inclination of the carriage B in the + direction exceeds the threshold value, the central processing unit 41 generates a signal for decelerating the rotation speed of the turning roller A (step S28). This signal is converted by the conversion unit 41d and transmitted from the transmission / reception unit 44 of the control device 40 to the central processing unit 31 via the transmission / reception unit 34 of the rotation control unit 30 (step S25).

Similarly, when it is determined in step S23 that the inclination of the minus direction of the carriage B exceeds the threshold value, the central processing unit 41 generates a signal for accelerating the rotation speed of the turning roller A (step S29). This signal is converted by the conversion unit 41d and transmitted from the transmission / reception unit 44 of the control device 40 to the central processing unit 31 via the transmission / reception unit 34 of the rotation control unit 30 (step S25).

In the turning roll A, the rotation speed is changed from the control device 40, and the current rotation is continued until a signal indicating that deceleration or acceleration is to be transmitted. When a signal indicating that the rotational speed should be changed is transmitted, a drive signal is output from the drive control unit 31c to the drive motor 36 of the drive roll 12 in accordance with the instructed signal, and the drive roll 12 according to this drive signal. Is controlled (step S14). The rotation of the turning roll A is continued while maintaining the same state until a signal indicating that the controller 40 decelerates or accelerates is transmitted from the control device 40 in step S14.

When the travel of the carriage B is stopped in step S27, a signal indicating that the travel should be stopped is converted by the conversion unit 41d of the central processing unit 41, and is transmitted from the transmission / reception unit 44 via the transmission / reception unit 34 of the rotation control unit 30. This is transmitted to the central processing unit 31. And the signal which stops the drive motor 36 is output from the drive control part 31c, the drive roll 12 stops, and the turning roll A stops.

It is possible to weld the flange 2 to the cylindrical tube 1 arranged horizontally as described above.

Next, the configuration of the welding apparatus according to the second embodiment will be described with reference to FIG. In addition, the same code | symbol is attached | subjected to the part which has the same part as the welding apparatus which concerns on 1st Example mentioned above, and the same function, and description is abbreviate | omitted.

The welding apparatus according to the second embodiment shown in FIG. 5 uses a positioner C as a rotational drive device. The fillet welded to the intersection of the flange 2 and the cylindrical tube 1 by the carriage B mounted on the outer periphery of the cylindrical tube 1 while rotating the flange 2 attached to the positioner C and the cylindrical tube 1 at a desired angle. It is comprised so that it can perform.

The positioner C includes a rotary table 51 that rotates the flange 2 and the cylindrical tube, a casing 52 that houses a drive motor 36 that rotationally drives the rotary table 51, a frame 53 that supports the rotary table 51 and the casing 52, and a first embodiment. And a control panel 54 containing the rotation control unit 30 in the example.

The rotary table 51 is formed in a disc shape, and is connected to and driven by the drive motor 36 via a shaft 51a. A plurality of grooves are formed radially on the surface of the rotary table 51, and the flange 2 is directly attached by bolts or the like using the grooves. When attaching a member to be welded to the rotary table 51, it is also possible to attach a chuck to the groove and use the chuck. That is, when attaching the flange 2 to be welded to the turntable 51, it is possible to use a bolt directly or using a chuck.

A shaft 55 a to which a sector gear 55 b is fixed is provided on both side surfaces (the front side and the other side in FIG. 5) of the casing 52, and the shaft 55 a is rotatably supported by the frame 53. The frame 53 is provided with a handle 55c. The handle 55c and the sector gear 55b are connected via a gear train (not shown). By rotating the handle 55c, the sector gear 55b is driven to rotate the rotary table 51. It is comprised so that it can set to a desired angle.

In the welding apparatus configured as described above, the flange 2 and the cylindrical tube 1 are preliminarily welded, the handle 55c is rotated to tilt the rotary table 51, and the flange 2 is attached to the rotary table 51. The angle at which the rotary table 51 is tilted is not limited as long as the operation of attaching the cylindrical tube 1 and the flange 2 temporarily welded to the rotary table 51 can be performed safely and smoothly. good.

After attaching the flange 2 and the cylindrical tube 1 to the rotary table 51, the handle 55c is rotated and set to a desired angle. At this time, the desired angle may be an angle at which the carriage B mounted on the outer periphery of the cylindrical tube 1 can achieve good welding, and is appropriately set according to conditions such as the diameter and thickness of the cylindrical tube 1. It is preferable.

After setting the rotary table 51 to a desired angle, mounting the carriage B on the outer periphery of the cylindrical tube 1 completes the welding setup for the flange 2 and the cylindrical tube 1. The carriage B mounted on the cylindrical tube 1 is also inclined in the direction intersecting with the traveling direction. However, by configuring the inclination detector 46 so as to detect only the inclination with respect to the traveling direction, the carriage B can be detected. It is possible to stably detect the forward tilt or the rear tilt in the traveling direction.

In the state where the carriage B is mounted on the outer periphery of the cylindrical tube 1 as described above, the flange 2 is attached to the outer peripheral surface of the cylindrical tube 1 of the carriage B in accordance with the inclination in the direction intersecting the traveling direction of the carriage B. Parallel component force is acting. For this reason, when the carriage B travels on the outer periphery of the cylindrical tube 1, the roller provided at the tip of the arm 25 presses the flange 2, and the carriage B can be guided along the surface of the flange 2.

Therefore, as in the first embodiment, the welding torch 20 mounted on the carriage B starts welding the portion to be welded between the flange 2 and the cylindrical tube 1 and starts rotating the rotary table 51 of the positioner C. At the same time, the target welding can be performed by starting the traveling of the carriage B.

When the tilt detector 46 detects that the carriage B is tilted forward or backward in the traveling direction, control is performed to accelerate or decelerate the rotation of the rotary table 51 so as to correct the detected forward tilt or backward tilt. Thus, it is possible to perform stable welding on a portion to be welded between the flange 2 and the cylindrical tube 1.

The welding apparatus according to the present invention is advantageous when welding a cylindrical tube having a large outer diameter and whose outer peripheral surface does not interfere with the bottom surface of the carriage when the carriage is placed at the highest position.

A Turning roll B Cart C Positioner 1 Cylindrical tube 2 Flange 11 Frame 11a Body 11b Rail 11c Shaft 11d Sprocket wheel 12

Drive roll

12a, 13a Bracket 12b,

13b Bearing

12c, 13c Fixing screw 13 Roller 14 Control panel 20 Welding torch 21 Casing Wheel 23 Torch holder 24 Operation panel 25 Arm 26 Lever 30 Rotation control unit 40

Control device

31, 41

Central processing unit

31a, 41a

Comparison processing unit

31b,

41b Storage unit

31c, 41c

Drive control unit

31d,

41d Conversion unit

32, 42

Input Unit

33, 43

output unit

34, 44 transmission /

reception unit

35, 45

operation switch

36, 48 Drive motor 46 Tilt detector 47 Welding current detector 51 Rotary table 51a Shaft 52 Casing 53 Frame 54 Control panel 55a Shaft 55b Sector gear 55c Handle

Claims

A welding apparatus for welding a member to be welded to a cylindrical tube,
A rotary drive device for mounting and rotating a cylindrical tube and a member to be welded to the cylindrical tube;
A rotation control unit for controlling rotation of the rotation driving device;
A welding torch for welding the cylindrical tube and the member to be welded, and a carriage mounted on the outer periphery of the cylindrical tube mounted on the rotary drive device;
The cart is provided with a tilt detector that detects the tilt of the cart in the traveling direction. When the tilt of the cart is detected by the tilt detector, the rotation driving device is detected according to the detected tilt direction. A welding apparatus comprising: a control device that generates an instruction signal for accelerating or decelerating the rotation driving device to the rotation control unit.
The control device compares the welding current at the time of starting welding with the current welding current, and when detecting that the current welding current is larger than the welding current at the time of starting welding, for the cylindrical tube, 2. The welding apparatus according to claim 1, wherein the traveling of the carriage is stopped when welding of the entire circumference is finished, and an instruction signal for stopping the rotation is generated by the rotation control unit of the rotation driving device.
The welding apparatus according to claim 1 or 2, wherein the rotation driving device is a turning roll for mounting and rotating a cylindrical tube in a horizontal direction.
The welding apparatus according to claim 1 or 2, wherein the rotation driving device is a positioner configured to rotate a mounted cylindrical tube at a desired angle.