JPH0378185B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a gas-shielded arc welding device for railway rails, and in particular to automation and quality improvement of rail welding. [Prior Art] Rail welding using the arc welding method is difficult to automate due to its complicated cross-sectional shape, and is generally performed by hand using the enclosed arc welding method. This enclosed arc welding method involves enclosing the bottom and side surfaces of rail ends facing each other with a gap of approximately 17mm between them, with copper blocks that match the shape of the rail.
This is a method of manual welding in a downward position using a low-hydrogen coated arc welding rod. [Problems to be solved by the invention] As mentioned above, since the enclosed arc welding method is manual welding, the quality of the welding depends on the skill of the welding operator, the welding time is relatively long, and the operator is unable to weld. There is a problem that you are restricted to the job while you are working. This invention was made in view of this situation,
By automating the management and control of welding conditions, we are able to stably supply high-quality joints, and
The purpose of the present invention is to provide a rail gas-shielded arc welding device that achieves complete automation and high efficiency of rail welding. [Means for Solving the Problems] The gas-shielded arc welding device for rails of the present invention includes a welding machine main body, a welding chamber, and a control device for controlling these. The welding machine body includes a welding torch section having an elongated welding nozzle, a welding wire feeding mechanism having a welding wire feeding motor that feeds the welding wire to the welding torch section, and a welding wire feeding mechanism that moves the welding torch section in horizontal and vertical directions. The welding machine is equipped with an X/Y axis movement mechanism having an X/Y axis movement motor and an X/Y axis position detection sensor, and a clamp mechanism that fixes the welding machine main body to the rail, which is the material to be welded. The welding chamber is internally equipped with a shielding gas outlet and a pair of movable water-cooled side abutments that surround the rail from the sides, and is equipped with a side abutment drive motor externally that drives these movable water-cooled side abutments, and is connected to the welding machine body. Insert the welding nozzle and isolate the part of the rail to be welded from the outside air. The control device includes a rail position detection means that determines the welding position of the welding nozzle with respect to the rail based on the detection signal of the Y-axis position detection sensor, a welding current detection sensor that detects the welding current flowing through the welding nozzle, and a welding current detection means that determines the welding position of the welding nozzle with respect to the rail based on the detection signal of the Y-axis position detection sensor. Single side uranami welding for the rail, gas shield arc welding for the rail bottom, rail belly,
Welding method of performing electrogas arc welding on the head and welding current corresponding to each welding method,
a storage section that stores welding conditions such as welding voltage and welding speed; an information processing section that selects and outputs a welding method and welding conditions according to the rail welding position from the storage section based on the output of the rail position detection means; and information of the information processing section. and a drive control section that compares and calculates information from the detection sensors of each drive section of the welding machine main body and outputs a drive signal for each drive motor based on the calculation result to perform feedback control. The drive control section of this control device compares the detected value of the welding current detection sensor with a target value during welding, outputs a drive signal to the Y-axis moving motor so that the welding nozzle maintains a predetermined distance from the welding part, and also outputs a drive signal to the Y-axis moving motor. The movable water-cooled side abutment is controlled by outputting a drive signal to the side abutment drive motor so that the movable water-cooled side abutment surrounds the rail based on the rail belly and head position signals from the position detection means. [Function] This invention has a welding chamber that isolates the welded part from the outside air, and the control device controls the welding nozzle to carry out single-sided uranami welding on the first layer position at the bottom of the rail and gas-shielded arc welding on the bottom of the rail. The welding method is electrogas arc welding for the rail abdomen and head, and the welding conditions are controlled to correspond to each welding method, such as welding current, welding voltage, and welding speed. Based on the detection value of the detection sensor, the Y-axis moving motor is driven and controlled to maintain the welding nozzle at a predetermined distance from the welding part so that the welding current is kept constant. Based on the position signal, the side drive motor is driven and controlled so that the movable water-cooled side abutment surrounds the rail, and narrow gap welding using the gas-shielded arc welding method is performed continuously and fully automatically. [Embodiment] Fig. 1 is a perspective view showing an embodiment of the present invention, and in the figure, 1 and 1' are rails to be welded;
2 is a welding chamber, 3 is a welding torch part, 4, 4'
are an X-axis movement block and a Y-axis movement block that move the welding torch section 2 in the horizontal and vertical directions. 5 is a welding wire feeding motor, 6 is a welding wire, 7 is a wire reel, 8 is a clamp mechanism for fixing the welding machine main body to the rail, and 9 is a welding current detection sensor. The welding torch section 3 consists of a long, narrow-diameter welding nozzle 31, a nozzle rotation motor 32, and a nozzle rotation speed detection sensor 33.As shown in FIG. , the welding nozzle 31 is connected to the nozzle rotation motor 3
2 to ensure melting of the inner surface of the groove. An X-axis moving block 4 and a Y-axis moving block 4' for moving this welding torch section 3 are composed of X-axis/Y-axis moving motors 41, 41', X-axis/Y-axis moving speed detection sensors 42, 42', and X-axis - Equipped with Y-axis position detection sensors 43, 43. The welding wire feed motor 5 includes a wire feed speed detection sensor 51 and feeds the welding wire 6 to the welding torch section 3 via a pipe 52. The welding chamber 2 is used to isolate the welded parts of the rails 1 and 1' from the outside air and obtain a high-quality joint.As shown in Fig. Movable water-cooled side pad 21,
Shielding gas side jet port 22 provided at 21',
22' and a head outlet 23 for sending shielding gas from above the rail 1 to the rail head. 24 is a side abutment drive motor, and 25 is a side abutment drive shaft. Further, 26, 26' are gas inlets that send shielding gas to the side nozzles 22, 22', 27 are gas inlets 28, 28' that send shielding gas to the head nozzles, are movable water-cooled side pads 21,
21' is a cooling water inlet, and 29 and 29' are cooling water outlets. At the bottom of this welding chamber 2, a backing material 200 and tab materials 201, 201' can be placed. FIG. 4 is a block diagram showing the control device of this embodiment. In the figure, 401 is a rail position detection means, which detects the Y-axis position by detecting the amount of rise of the Y-axis moving block 4' which rises as welding progresses. sensor 4
3', the welding height is determined from the amount of rise, and the welding position of the welding nozzle 31 with respect to the rails 1, 1' is output. 402 is a storage unit for storing welding methods and welding conditions for each part of the rail according to the shape of the rail; 403 is a storage unit that stores welding methods and welding conditions according to the position of the rail in response to an input signal from the rail position detection means 401; 404 is a drive control unit that controls the operation of the drive motor 405 of each drive unit of the welding device, and an input unit that takes in information from the detection sensor of each drive unit. unit 406, and a calculation unit 4 that compares and calculates information from the information processing unit 403 and input unit 406.
07 and a drive output unit 408 that outputs the calculation results of the calculation unit 407 to each drive motor 405. Feedback control of the drive control section 404 controls the nozzle circuit speed, wire feeding speed, movement position of the X-ray movement block, movement speed of the X-axis movement block, and welding current control.
That is, the nozzle rotation speed control is performed by detecting the rotation speed of the nozzle rotation motor 32 using the nozzle rotation speed detection sensor 33 and performing feedback control. Further, in the case of wire feeding speed control, the rotational speed of the welding wire feeding motor 5 is detected by a wire feeding speed detection sensor 51, and the movement position control and movement speed control of the X-axis moving block are carried out by the X-axis position detection sensor 43, respectively. , the position and rotational speed of the X-axis moving motor 41 are detected by the X-axis moving speed detection sensor 42 to perform feedback control. Further, by utilizing the fact that the welding current changes as the wire protrusion length changes, the current value is detected by the welding current detection sensor 9 and compared with the target value to drive the Y-axis movement motor 41' to move the Y-axis. It is controlled by moving the block 4' up and down. Furthermore, the water-cooled side abutment movement control is performed by driving the side abutment drive motor 24 based on the rail position signal from the rail position detection means 401 to move the movable water-cooled side abutment 20, 21'. . Next, the operation of welding the rails 1, 1' according to the above embodiment will be explained with reference to FIGS. 3 to 6. FIG. 5 shows the rail 1,
6 is a sectional view of the welding chamber 2. In step 501, welding of rails 1 and 1' is started, and in step 502, first layer welding is performed at the first layer position at the bottom of the rail using single-sided back wave welding.
After confirming a predetermined position using the Y-axis position detection sensor 43', which is the rail position detection means 401, in step 503, the bottom of the rail is welded. The welding of the bottom of the rail is done in step 504 in the storage section 40.
In step 505, the information processing section 403 selects the welding method stored in step 2, that is, multi-layer welding using normal gas-shielded arc welding, and in step 505, welding conditions according to the welding position. This is done by outputting to the control unit 406. This multi-layer welding of the bottom of the rail is performed with the movable water-cooled side abutments 21, 21' separated from the rails 1, 1' as shown in FIG. Next, in step 507, the height position of the rail is determined. As a result of welding current control, the Y-axis movement block 4' rises as welding progresses, and the Y-axis position detection sensor 43' detects the amount of rise, and determines the height position of the rail. The rail position detection means 401 determines the welding height at each point from the amount, and the rail 1 of the welding nozzle 31,
Determine the welding position for 1. After detecting the top end position of the rail bottom, step
In step 508, the information processing unit 403 selects the welding method for the rail abdomen and head from the storage unit 402. This welding method is electrogas arc welding. Therefore, in step 509, the drive control unit 404 outputs a drive signal to the side abutment drive motor 24 in response to the rail belly and head position signals from the rail position detection means 401, and as shown in FIG. The type water-cooled side supports 21, 21' are moved to surround the rail from the side. In step 510, welding conditions are selected according to the rail height position, and in step 511, each drive section is controlled under the welding conditions according to the rail height position.
Weld the belly and head of the rail, and then
After determining the welding end position of the rail in step 512, welding of the rail is finished in step 513. In other words, the target value of each controlled variable, the movable water-cooled side pads 21, 2 are adjusted as programmed in advance.
1' movement command, shield gas nozzle opening/closing command,
By outputting gas flow rate switching commands, etc., welding is performed continuously and fully automatically from start to finish. The welding voltage is controlled by outputting a target value to an external terminal of the welding power source, and the opening/closing and flow rate switching of the shielding gas is performed by providing several electromagnetic valves in the gas cylinder. Further, in this embodiment, the method of rotating the welding nozzle is used to ensure penetration of the inner surface of the groove, but other methods may be used to ensure penetration of the inner surface of the groove. Table 1 shows a comparison of the tensile test results of welded joints when rails were welded using the above-mentioned example with that of conventional manual enclosed arc welding, and Table 2 shows the arc times for both types of welding. .

【table】

[Table] The test rail was an ordinary high carbon steel rail with a weight of 60 kg/m, and the welding conditions for each part of the rail shown in Figure 7 were as shown in Table 3.

[Table] From the above results, it is clear that the rail welding according to the present invention has higher quality and higher efficiency than conventional welding. [Effects of the Invention] As described above, the rail gas-shielded arc welding device of the present invention performs single-sided urana welding on the initial layer position of the rail bottom, gas-shielded arc welding on the rail bottom, rail abdomen, The head is welded using an electrogas arc solution welding method, and the welding conditions are the welding current, welding voltage, and welding speed that correspond to each of these welding methods, and the welding current is controlled to be kept constant during welding. In addition, when welding the rail belly and head, movable water-cooled side supports surround the rail from the sides, and rail welding is performed continuously and fully automatically, so it is not affected by the skill of the worker. High-quality welding can be performed in a short time and with high efficiency, and it has the effect of greatly contributing to labor savings in rail welding. Although the welding device of the present invention was developed for rail welding, it can also be used for butt welding of small members, shaped steel, etc. by changing the welding chamber, clamp mechanism shape, and control program.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of the invention, Fig. 2 is a perspective view showing an embodiment of the invention;
The figure is a perspective view of the welding torch, Figure 3 is a side sectional view of the welding chamber, Figure 4 is a block diagram of the control device, Figure 5 is a control flowchart, and Figure 6 is a diagram of the movable water-cooled side pad. FIG. 7, a side view of the welding chamber showing the operation, is an explanatory diagram showing welding conditions depending on the rail position. 1, 1'...Rail, 2...Welding chamber, 3
...Welding torch section, 4...X-axis moving block,
4'... Y-axis moving block, 5... Welding wire feeding motor, 6... Welding wire, 7... Wire reel, 8... Clamp mechanism, 21, 21'... Movable water-cooled side support, 22 , 22'... Shield gas side outlet, 23... Head outlet, 200... Backing material, 201, 201'... Tab plate, 401...
Rail position detection means, 402... Storage section, 403
... Information processing section, 404 ... Drive control section, 405
... Drive motor, 406 ... Input section, 407 ...
Arithmetic unit, 408... Drive output unit.

Claims (1)

[Claims] 1. A welding torch portion having an elongated welding nozzle;
a welding wire feeding mechanism having a welding wire feeding motor that feeds the welding wire to the welding torch; an X/Y axis movement motor that moves the welding torch in horizontal and vertical directions; and an X/Y axis position. A welding machine main body equipped with an X/Y axis movement mechanism having a detection sensor and a clamping mechanism that fixes the welding machine main body to the rail, which is the material to be welded; A welding chamber is provided with water-cooled side abutments inside, a side abutment drive motor for driving these movable water-cooled side abutments is provided on the outside, the welding nozzle is inserted, and the part to be welded of the rail is isolated from the outside air. ; a rail position detection means for determining the welding position of the welding nozzle with respect to the rail from the detection signal of the Y-axis position detection sensor; a welding current detection sensor for detecting the welding current flowing through the welding nozzle; Welding methods include single-sided uranami welding, gas-shielded arc welding for the rail bottom, and electrogas arc welding for the rail belly and head, and welding current, welding voltage, and welding speed corresponding to each welding method. a storage unit that stores conditions; an information processing unit that selects and outputs a welding method and welding conditions according to the rail welding position from the storage unit based on the output of the rail position detection means; and information of the information processing unit and the welding machine main body. and a drive control unit that compares and calculates information from the detection sensors of the drive unit and outputs drive signals for each drive motor based on the calculation results for feedback control, and the drive control unit is a welding unit. At the same time, the detection value of the welding current detection sensor is compared with the target value, and a drive signal is output to the Y-axis moving motor so that the welding nozzle maintains a predetermined distance from the welding part. A rail gas shield arc welding device characterized in that a position signal outputs a drive signal to a side abutment drive motor so that the movable water-cooled side abutment surrounds the rail. 2. The welding torch is equipped with a welding nozzle whose welding nozzle tip is offset from the welding wire passage hole and a motor for rotating the nozzle to ensure penetration of the inner surface of the groove. Gas shielded arc welding equipment for rails. 3. The drive control section outputs a drive signal to the nozzle rotation motor so that the rotation speed of the welding nozzle corresponds to the welding position of the welding nozzle with respect to the rail based on the output of the rail position detection means. A gas-shielded arc welding device for rails according to claim 2.