JPH0663750A - Groove shape detector in submerged arc welding for thick steel plates - Google Patents

Abstract

PURPOSE:To detect the change of a groove shape and a cross section of a groove and to allow welding conditions to follow it. CONSTITUTION:The groove shape detector traveling on a groove line prior to a welding torch in a submerged arc welding consists of a fixed supporting roller leg 11 for attaining the steel plate surface of either one side constituting the groove, a supporting roller leg 12 movable in the vertical direction pushed against the surface of the other steel plate for constituting the groove and two depth measuring roller legs 13 and 14 movable in the vertical and horizontal directions provided with globular bodies with the different diameter pushed against the groove inside on the tips. Further, the groove shape detector consists of position detectors 22-24 which detect the positions in the vertical direction of the movable supporting roller leg 12 and the two depth measuring roller legs 13 and 14, respectively, with the fixed supporting roller leg 11 as a reference and position detectors 25 and 26 which detect horizontal displacement in an orthogonal direction to the groove line of the two depth measuring roller legs 13 and 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to submerged arc welding of a thick steel plate whose groove shape changes depending on the position, such as square seam welding of a square steel pipe column in which a completely penetration welded portion and a partial penetration welded portion are mixed. In regard to the groove shape detecting device in FIG.

[0002]

2. Description of the Related Art As shown in FIG. 2, four steel plates 2a, 2b,
Assembling 2c and 2d into a box-shaped cross section, 4 corner seams 21
The a, 21b, 21c, and 21d are joined by submerged arc welding to manufacture square steel tubular columns (also called box columns) for middle- and high-rise buildings. When the thickness of the steel sheet is thick, the welding method of raising the inside of the groove by multiple passes was conventionally used, but it is quite normal that the manufacturing length of square steel tube column is over 10 m, and the work efficiency is extremely high. Low. Therefore, as shown in Japanese Patent Publication No. 51-19419, a welding method has been developed in which a plurality of torches are used and welding is performed in a single pass with a large current, and these are widely adopted today.

By the way, the above-mentioned square steel pipe column has a portion which simply functions as a column and a joint portion which is connected to a beam or the like and receives a horizontal force or moment. It is not necessary to perform full penetration welding over, if the joint part is joined with full penetration,
Partial melting in other parts is often sufficient. Since the length ratio of the joint is rather small, it goes without saying that limiting the complete penetration welding to the necessary parts is economical in terms of work efficiency, welding power, welding materials, etc. .

By the way, in submerged arc welding, since the welding apparatus automatically travels after the arc is started, it is not necessary for the operator to constantly operate it. Therefore, in the submerged arc welding of the square seam of the square steel pipe column, two seams on the same plane, for example, 21a and 21b in Fig. 2 are almost simultaneously used by the same operator in order to reduce the thermal strain and work efficiency. It is customary to carry out construction.

However, since the steel plates generally used for square steel tubular columns are thick, it is necessary to have a high level of technology even if only the entire length is welded under constant welding conditions. Attempting to change the depth requires cross-section measurement and frequent change operations by the operator, and in particular, fine adjustment of the welding speed requires advanced skill and experience, which makes welding extremely difficult and unreliable. I don't get.

[0006] Therefore, conventionally, the entire length is completely melted and welded in consideration of the uneconomical condition, or the joint portion is preliminarily welded to the lower part of the groove, and then the whole length is partially welded. Welding was done. Also,
Since groove processing is usually performed by gas cutting, even if the groove section is uniform in design, the cross-sectional shape or cross-sectional area is the entire length due to processing errors, steel plate assembly errors, steel plate deformation, etc. Not always constant over time. Therefore, it is necessary for the operator to measure the groove shape in advance.
Therefore, according to JP-A-55-106683, in arc automatic welding along the groove line of the welding base metal, both the width and the depth of the groove are detected prior to the welding position. While compensating for the delay between the detection point and the welding position, the above detection amount is calculated to obtain the change in groove cross-sectional area, and based on this, at least one of the welding speed and wire supply speed, and further the oscillation amplitude is adjusted In an automatic welding control method for controlling, and in an arc automatic welding device that travels along a groove line of a welding base metal, two detection rollers inserted into the groove line prior to a welding torch and this detection A detection device provided to detect the groove depth and the groove width on each of the rollers, and a detection amount detected by this detection device is calculated to calculate at least one of an appropriate welding speed and wire supply speed, and further an oscillation rate. Automatic welding control apparatus is disclosed which is characterized by comprising these determined width from a computing device that outputs to the drive circuit.

Further, regardless of the sectional shape, the center line of the groove is meandering or curved so that the center of the groove cross section and the tip of the torch gradually shift, and the welding state changes during automatic welding. Things happen. Therefore, Japanese Patent Publication Sho-57-433
According to Japanese Patent Laid-Open No. 54-54, there is disclosed a copying method of an automatic welding machine, which detects the left and right bends and wideness of the groove line by a copying mechanism composed of two guide wheels, and causes the welding nozzle to accurately follow the welding line. ing.

[0008]

In the welding operation in which the welding conditions are partially changed in this way, the entire length is completely welded or the joint portion is pre-welded under the groove. Since there is no technical problem, it is uneconomical to weld through the entire length with partial melting specifications, and there is an urgent need to correct it at the manufacturing site. Further, according to the automatic welding control method and apparatus of the above-mentioned JP-A-55-106683, only the width and depth of the groove in the groove of the symmetrical cross section can be detected. There is a defect that it cannot follow the shape detection of the general groove and the bending of the groove line. According to the copying method of the automatic welding machine in Japanese Patent Publication No. 57-43354, two detection wheels are provided on one side of the groove surface. Since only the contact is made, the bending of the groove line and the change of the width are detected, but they are not detected when the depth is changed, and therefore there is a drawback that the change of the groove cross-sectional area cannot be followed.

In order to obtain a sound weld, the weld metal must be filled in the groove and the surface must have an appropriate height. If the cross-sectional area of the groove is smaller than the specified value, the excess will be too large, so it is necessary to cut this part. Conversely, if the cross-sectional area of the groove is larger than the specified value, the weld metal inside the groove Is not filled, resulting in an undercut state that leaves a groove cross section, and it may be necessary to separately perform build-up welding on the insufficient portion, which is not preferable.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide a groove shape detecting device for detecting both the groove cross-sectional area and the bending at the same time so as to follow the welding machine or welding conditions. To do.

[0011]

DISCLOSURE OF THE INVENTION The present invention is a groove shape detecting device which travels on a groove line prior to a welding torch in submerged arc welding of thick steel plate, and one of the groove forming devices. It has a fixed support roller leg that reaches the surface of the steel plate, a vertically movable support roller leg that is pressed against the surface of the remaining steel plate that constitutes the groove, and a spherical body with a different diameter that is pressed into the groove inside the tip. Two sounding roller legs that are vertically and horizontally movable, and the movable support roller legs and 2 based on the fixed support roller legs.
And a detecting means for detecting the vertical position of each of the sounding roller legs, and a detecting means for detecting a horizontal displacement in a direction perpendicular to the groove line of the two sounding roller legs each having the spherical body at its tip. Is characterized by.

[0012]

[Operation] The principle of the groove shape detection of the present invention will be described with reference to FIGS. 1, 3, and 4. FIG. 1 is an overall view of welding equipment including a groove shape detecting device of the present invention. The groove shape detecting device 1 is a welding device 3 that travels on a traveling rail 5 that is installed in parallel with the steel material 2 that is the object to be welded and at substantially the same height.
It is connected to the control device 4 with a certain distance, and runs on the groove line of the steel material 2 as the object to be welded prior to the welding machine. When measuring the groove depth and the like, the surface of any one of the steel plates forming the groove is used as the height measurement standard.

FIG. 3 schematically shows the concept of the groove shape detecting device 1. It is downward from the main body 10 of the device 1 on both sides of the groove line formed by the steel materials 2 and 2 '. Two support roller legs 11, 12 are provided. One of the support roller legs 11 is fixed to the apparatus body 10 to support the apparatus body, and the other 12 is movable in the vertical direction with respect to the apparatus body, and the vertical position thereof can be measured. 2 support roller legs 1
Reference lower amount of protrusion from the main body of 1,12 (hereinafter, referred to as height) if the a h _1, h _2, respectively, the height h ₁ of the fixed-side support roller legs 11 is constant, the movable-side support Roller leg 12
The difference between the heights h ₂ and h ₁ represents the amount of misalignment based on the steel plate surface on the fixed side, and the average value of h ₁ and h ₂ is the difference between the two sides of the groove indicated by the two-dot chain line in FIG. Shows the average height surface of the steel plate surface.

Further, from the main body 10 of the groove shape detecting device 1 downward, the sounding roller legs 13 and 14 provided with two spherical bodies having radii R ₃ and R ₄ (R ₃ > R ₄ ) at the tip end are vertically arranged. Each sphere is pressed against the inner surface of the groove. If the height of the center of curvature of the spherical body is h ₃ and h ₄ , respectively, the average height of the steel plate surface at the center of the large spherical body is d ₁ , the depth from this center to the groove bottom. Sa d ₂ ,
The groove depth D from the average height surface of the steel plate surface, which is the sum of the above, is

[0015]

[Equation 1]

Therefore, irrespective of the groove angle 2α, h ₁ , h ₂ ,
It can be calculated from h ₃ , h ₄ and R ₃ , R ₄ . Of these, h ₁ , R ₃ , and R ₄ are values known by the device, and h ₂ , h ₃ , and
h ₄ is the value obtained by measurement. On the other hand, this groove shape detecting device 1 can detect the deviation amount x of the two spherical bodies 13, 14 in the groove width direction. If the inclination angle of the line connecting the centers of these two spherical bodies 13 and 14 is θ,

[0017]

[Equation 2]

Since α and θ can be obtained by the above, the width w of the groove is divided into w ₁ and w ₂ by a perpendicular line drawn from the apex of the bottom to the upper surface of the steel plate as shown in FIG.

[0019]

[Equation 3]

Can be calculated from D, α, θ,

[0021]

[Equation 4]

As a result, the groove cross-sectional area S can be obtained from the measurement results of x, h ₂ , h ₃ and h ₄ . Since the total welding area obtained by adding an appropriate extra amount to this cross-sectional area is determined, welding is performed by instructing the traveling speed of the welding apparatus and the welding wire supply speed of the welding apparatus. Further, the value of x can be used as it is as an instruction value of the displacement amount of the welding torch.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A groove shape detecting device according to an embodiment of the present invention will be described in detail with reference to FIGS. 5 is a front view of the groove shape detecting device 1, 10 is a casing (main body), 27
Is a support arm, 11 and 12 are support roller legs, 11 is a fixed support,
12 is a movable support, 13 and 14 are sounding roller legs, and the spherical body of 13 has a large diameter and 14 has a small diameter.

The casing 10 comprises a lower casing 10a to which supporting roller legs and sounding roller legs are attached, and an upper casing 10b which is fitted to the lower casing 10a and is connected to a welding device or a control device via a supporting arm 27. . The spherical body of the sounding rollers 13 and 14 is a sphere in principle as described above with reference to FIGS. 3 and 4, but in this embodiment, as will be described later with reference to FIG. A disc-shaped roller having a tire section with a circular cross section is used. That is, as long as the profile of the tip end portion viewed from the groove direction is circular, any measurement may be performed.

FIG. 6 is a side view as seen from the left side of FIG. 5, in which the support roller legs 11 and 12 are separately arranged on both sides of the groove and are on the surface of each steel plate, while the spherical shape is spherical. The rollers 13 and 14 as the body are pressed against the inner surface of the groove.
Traveling rails such as welding equipment or control equipment,
Since the groove shape detection device 1 is not always at the same height as the traveling steel material 2, the upper casing 10b is supported by the support arm 27 and the lower casing 10a is connected to the upper casing 10b in order to cope with height variations. Has a structure in which it is suspended by a rod 108 provided with a spring so that it can be independently moved up and down. Further, since the distance from the traveling rail is not constant, the connecting portion 27d between the support arm 27 and the upper casing 10b can be adjusted in the direction perpendicular to the groove line.

The support arm 27 that supports the casing and is connected to the welding equipment is divided into a detection device side portion 27a and a welding equipment side portion 27b, which are connected by a hinge portion 27c.
When the detector is not in use, it can be removed, or can be temporarily retracted upward as shown by the chain double-dashed line in FIG. Since the groove shape detecting device 1 needs to travel on the groove line prior to the welding torch, the support arm 27 must be provided in front of the welding device 3. If the groove shape detecting device 1 is too close to the welding torch, the flux supply is hindered, and it is inconvenient when the weld metal flows forward. Moreover, the calculation time from measurement to welding is also required.
Needless to say, the detection position information is also recorded when the groove shape is detected so that the welding conditions are met when the welding torch reaches the measurement position.

As described in the section "Operation", in the present invention, the support roller leg 12 and the sounding roller legs 13 and 14 are vertically movable with respect to the lower casing 10a, and the height of the support roller leg 11 is increased. The vertical height of each can be measured based on. FIG. 7 is a partial side view illustrating a measuring mechanism using the support roller leg 12 as an example. A roller 12a is inserted into and attached to a cage 12b at a lower end portion of a rod 12c which moves up and down, and can support a light load while rolling in any direction on a plane orthogonal to the axis of the rod. Rod 12
c is always pressed downward by the spring 12d. A connecting plate 12e is attached to the upper end of the rod 12c,
It is connected to the position detectors 22 that are adjacently arranged in parallel. As the position detector 22, an electric displacement measuring device such as a differential transformer, a linear potentiometer, a resistance type position detector or the like is suitable.

On the other hand, in the present invention, the sounding roller legs 13,
In the state where two spherical bodies with different diameters at the tip of 14 are pressed against the inner wall of the groove, the deviation amount in the direction perpendicular to the groove line of the center of the two spherical bodies, that is, in the section of "action" x
Can be measured. Therefore, the target position of the torch tip with respect to the groove can be accurately determined based on both the information on the amount of horizontal deviation and the groove depth, and a sound weld can be realized.

FIG. 8 is a plan view seen from the upper surface of the lower casing 10a. The supporting roller legs 11, 12 and the sounding roller legs 13,
In each of the fourteen, only the upper end of the vertical rod appears and the center position of each is shown. The same applies to the position detector 22 corresponding to the support roller leg 12 and the position detectors 23 and 24 corresponding to the sounding roller legs 13 and 14. Sounding roller legs 13, 14
Are mounted on the block 31 and guide shafts 32a, 32b on both sides
Since it is guided by, the entire block 31 can be moved left and right while maintaining parallel to the groove line. The amount of movement is a block
The steel plate 33 attached to the end of the 31 is the position detectors 25, 26.
Can be detected by going in and out. FIG. 9 is a partial side view of the vicinity of the steel plate 33 and the position detector 25.

The shape and size of the spherical body attached to the tips of the sounding roller legs 13 and 14 may be replaced with those of an appropriate size and shape according to the groove to be measured, but the important point is the tire. The radius of the part, for example width 37
mm, 59 mm deep V-shaped groove, the larger radius 10 mm,
It is recommended to use the smaller one with a radius of 8 mm. FIG. 10 shows an example of the structure of the sounding roller leg 13. 13a is a spherical body, the cross section of the tire portion is circular with a radius of 6.5 mm, the disk of the boss portion has a radius of 14 mm, and it is attached to the leg body 13d by the central axis 13b and the bearing 13c. At the vertical position measurement part, measure the center height h ₃ of the tire part. The width of the groove in this example is 18 mm and the depth is 21 mm.

FIG. 11 shows the configuration of this embodiment. Reference numeral 1 is a groove shape detecting device, 3 is a welding device, 4 is a control device, 41 is an operation part, and 42 is a display part. That is, the groove shape is detected by the operation portion 41, and the groove cross-sectional area S is determined in the control portion 4 from the measurement results of x, h ₂ , h ₃ , and h ₄ as described in the section “Operation”. The welding conditions are calculated, the welding conditions are determined, and the welding device 3 is instructed. The measured value can be visually observed on the display portion and can be recorded by a printer.

[0032]

According to the present invention, the groove shape having an arbitrary asymmetrical cross section, that is, the cross-sectional area, the horizontal displacement and the amount of bending are measured, and the welding apparatus is made to follow this, so that proper welding can be performed efficiently. It has an excellent effect that it can be performed. When the groove cross section measured according to the present invention was actually measured, the groove depth was 3%, the groove width was 4%, and the groove cross sectional area was 2%.
%, And even with an actual amount of deposited metal, the error was within 5%, which was a good result, the burden on the operator was reduced, and the quality was stable.

[Brief description of drawings]

FIG. 1 is a front view showing the overall configuration of the present invention.

FIG. 2 is a perspective view of a square steel pipe column according to the present invention.

FIG. 3 is a conceptual diagram showing the measurement principle of the present invention.

FIG. 4 is a conceptual diagram showing the measurement principle of the present invention.

FIG. 5 is a front view showing an embodiment of the present invention.

FIG. 6 is a side view showing an embodiment of the present invention.

FIG. 7 is a partial side view of the embodiment of the present invention.

FIG. 8 is a partial plan view of the embodiment of the present invention.

FIG. 9 is a partial side view of the embodiment of the present invention.

FIG. 10 is a partial side view of the embodiment of the present invention.

FIG. 11 is a configuration diagram according to an embodiment of the present invention.

[Explanation of symbols]

 1 Shape detection device 2 Steel material 3 Welding device 4 Control device 5 Traveling rail 10 Casing 11, 12 Support roller leg 13, 14 Sounding roller leg 22-26 Position detector 27, 28 Support arm

Claims (1)

[Claims] 1. A groove shape detecting device for traveling on a groove line prior to a welding torch in submerged arc welding of thick steel plate, wherein a fixed support roller reaches the surface of one of the steel plates forming the groove. A leg, a vertically movable support roller leg that is pressed against the surface of the remaining steel plate that constitutes the groove, and a spherical body with a different diameter that is pressed against the inside of the groove at the tip. Two sounding roller legs, detection means for respectively detecting the vertical position of the movable supporting roller leg and the two sounding roller legs with the fixed supporting roller leg as a reference, and two equipped with the spherical body at the tip. A groove shape detecting device in submerged arc welding of thick steel plate, comprising: a detecting means for detecting a horizontal displacement of the sounding roller leg in a direction perpendicular to the groove line.