JPH0748069B2 - Ultrasonic flaw detector for ERW pipe - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an apparatus for ultrasonically flaw-detecting a welding defect of a seam portion on a production line of an electric resistance welded pipe.

[Conventional technology]

In recent years, in order to improve the operation rate and yield of pipe manufacturing mills, a loop car has been added to the tail of the coil that is being used for pipe manufacturing, instead of the so-called coil pipe manufacturing system, in which setup is changed for each coil and plate passing is performed. A so-called continuous pipe-making method is being adopted in which the heads of different coils are sequentially welded to produce a pipe while obtaining a time margin.

In this case, the widths and wall thicknesses of the coils to be connected are not necessarily the same, so that the diameter and wall thickness of the electric resistance welded pipe to be manufactured also differ. Therefore, even in ultrasonic flaw detectors for seams, which have been widely used to guarantee the quality of ERW pipes, flaw detection can be continued without any trouble by quick setup change for such different diameter pipes and thick wall pipes. It is hoped that this will be possible.

As a device for this purpose, a device as shown in FIG. 6 has been conventionally proposed.

FIG. 6 is a perspective view showing a conventional flaw detection device (Japanese Utility Model Publication No. 56-25414), where 51 is a fixed frame, 52 is a flaw detection device supported by the fixed frame 51, and P is an electric resistance welded pipe. . The electric resistance welded pipe P is arranged so that the seam portion S is located above and is transferred in the arrow direction. Above the transfer area of the electric resistance welded pipe P, the flaw detection device 52 uses the fixing frame 51 and the mounting frame 53. Have been installed.

A plurality of guide rolls 54 are used on the front of the mounting frame 53 to
An arc-shaped segment 55 having 55a is supported, and a support frame 56 is mounted on the front surface of this segment 55, and links 61, 62 are provided via a rotary shaft 57 and an air cylinder 58 provided on the support frame 56. A parallel link mechanism composed of 63, 64 is supported. A holding frame 65 is provided for the link 64 that constitutes the parallel link mechanism.
Is fixed and is provided with a diameter adjusting mechanism 66 and an arc frame 67.

The diameter adjusting mechanism 66 is provided with a pair of rolling rollers 66a, 66a which open and close according to the diameter of the electric resistance welded pipe P and whose mutual opening angles change.

Further, a probe 68 is attached to the arc frame 67 so as to be movable along the arc frame 67 toward the seam portion S side of the electric resistance welded pipe P via a mounting frame 67a.

Thus, in such a conventional device, for example, an electric resistance welded pipe P
Are moving parallel to the up and down direction, the rolling rollers 66a, 66a
The parallel link mechanism via the spherical bearing 61a,
62a rotates up and down around the rotation center, and the holding frame 65 moves up and down while maintaining a horizontal posture around the spherical bearing 61b as the rotation center, and the seam S of the electric resistance welded pipe P and the probe 68 are held. The positional relationship with is maintained.

Further, when the electric resistance welded pipe P is moved in parallel in the horizontal direction, the parallel link mechanism via the rolling rollers 66a, 66a uses the spherical bearings 61a, 61b of each joint as a fulcrum to form a rectangular shape to a parallelogram shape in the horizontal plane. Then, the holding frame 65 also moves horizontally while riding on the surface of the electric resistance welded pipe P, and the positional relationship between the seam S and the probe 68 does not change.

When the electric resistance welded pipe P tilts and changes in the vertical direction, the parallel link mechanism rotates around the spherical bearing 61b, and when the electric resistance pipe P tilts and changes in the horizontal direction, the parallel link mechanism keeps the rotating shaft 57 in a rectangular shape. Since the electric resistance welded pipe P rotates about the center, the relative positional relationship between the seam S and the probe 68 does not change. When the electric resistance welded pipe P is curved, the parallel link mechanism changes from a rectangular shape to a parallelogram so that the holding frame 65 follows the curve. When the seam portion of the electric resistance welded pipe P is displaced in the circumferential direction, the motor 55 inclines the segment 55 leftward and rightward along the guide roll 54, and the probe 68 follows the seam portion S. It will be moved.

[Problems to be Solved by the Invention]

By the way, in such a conventional ultrasonic flaw detector, the probe 68 is attached to the seam S depending on the posture of the electric resistance welded pipe P.
However, on the contrary, it is easy to cause a positional deviation due to the sliding operation of each joint portion, and when the diameter of the electric resistance welded pipe P is set up, the rolling roller 66a in the diameter adjusting mechanism 66 is used. Must be operated by the handle 66b, and the position of each probe 68 must be manually adjusted along the arc frame 67 according to the diameter and wall thickness of the electric resistance welded pipe P. There is a problem that it takes skill to adjust the position of the probe 68, which is required for about a single piece, in a short time, and quick setup change is difficult.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ultrasonic flaw detector for an electric resistance welded pipe capable of quickly and accurately changing the thickness and the pipe diameter. To provide.

[Means for Solving the Problems]

An ultrasonic flaw detector for an electric resistance welded pipe according to the present invention includes an elevating frame that is supported so as to be movable up and down with respect to a moving range of the electric resistance welding pipe, and left and right sides of the elevating frame that are orthogonal to the moving direction of the electric resistance welding pipe. With respect to the holding base, which is movably supported with respect to the direction, is provided with a follow-up roller that rolls on the lower end of the electric resistance welded pipe, and follows the movement in the left, right, up, and down directions. A follow-up mechanism, which is supported so as to be movable in the left and right directions of the electric resistance welded pipe, has a support base at the lower end portion and a support base having a follower roller that rolls on the electric resistance welded pipe and moves in the circumferential direction thereof; Equipped on the base, moving means in the direction parallel to the tangent to the surface near both sides of the seam of the electric resistance welded pipe, moving means in the direction parallel to the normal line, and around the axis parallel to the pipe axis of the electric resistance welded pipe. And a copying mechanism that has rotating means that rotate independently of each other, and at least one of the copying mechanisms supported by the copying mechanism. Characterized by comprising a contactor.

[Action]

According to the present invention, the setup can be automatically changed without using the calibration pipe, and the skip distance of the probe can be quickly set by the three-axis mechanism including the rotating means in the copying mechanism.

〔Example〕

Hereinafter, the present invention will be specifically described with reference to the drawings illustrating the embodiments. FIG. 1 is a front view of an ultrasonic flaw detector for an electric resistance welded pipe according to the present invention (hereinafter referred to as “invention device”), and FIG. 2 is a left side view of the present invention device, in which 1 is an ultrasonic flaw detector, Reference numeral 2 denotes a gantry, and P denotes an electric resistance welded pipe which is an object to be inspected.

As shown in FIG. 1, the electric resistance welded pipe P is adapted to be transferred in the direction of the arrow by the chain conveyor 3 with the seam S thereof right above, and above the transfer region of the electric resistance welded pipe P. An ultrasonic flaw detector 1 is arranged on a pedestal 2 so as to be able to move up and down with respect to the moving range of the electric resistance welded pipe P via an elevating frame 4.

The elevating frame 4 is arranged so that it can be vertically moved by using a linear bearing 6 on a vertically oriented guide member 5 provided on the gantry 2.
An air cylinder 7 provided on the gantry 2 is positioned and held at an arbitrary height position above the stopper 8. The stopper 8 is a guide member 9 provided on the base 2.
In addition, it is arranged so as to be movable up and down, and is moved and positioned upward and downward by a motor 11 via a linear bearing 10 to regulate the lower limit of the elevating frame 4.

On the lower surface of the elevating frame 4, there is provided a holding table 21 that constitutes a follow-up mechanism 20 so as to be movable in the left and right horizontal directions orthogonal to the transfer direction of the electric resistance welded pipe P via a linear bearing 12, and this holding table 21 is also provided. 2, a plurality of flaw detection heads 49 are supported via a seam copying mechanism 40 .

FIG. 3 is an exploded perspective view of the main part of the follow-up mechanism 20. As is clear from FIG. 3 (a), the holding table 21 has a rod-shaped frame 21a arranged in parallel, a downwardly U-shaped frame 21b, and L-shaped side frames 21c, 21c extending between both ends thereof. A pair of left and right follower rollers 24 via downward Y-shaped holders 23f and 23r at the lower ends of the support rods 22f and 22r hanging from both ends of the side frames 21c and 21c.
The f and 24r are provided in a C-shape in a front view, and the front and rear pair of left and right follower rollers 24f and 24r are rolled on the surface of the electric resistance welded pipe P while straddling the electric resistance welded pipe P. There is.

As a result, when the electric resistance welded pipe P moves leftward or rightward in FIG. 1, the follower rollers 24f, 24r are pressed leftward or rightward in accordance with this movement, and as a result, the holding table 21 is moved by the copying mechanism 40 ,
With the flaw detection head 49, it is moved to the left or right with respect to the elevating frame 4 by the linear bearing 12, so that the force applied to both follower rollers 24f, 24r from the electric resistance welded pipe P becomes equal.
In other words, both follower rollers 24f and 24r are moved to the position where they cross the electric resistance welded pipe P to the left and right without any deviation.

Immediately below the holding table 21, as shown in FIG.
9. A support base 31 and a support base 41 that move in a direction orthogonal to the moving direction of the electric resistance welded pipe P are hung through the interlocking frame 30, and the follow-up mechanism 20 is configured by these.

The suspension base 29 has linear bearings 29 at both front and rear ends.
The holding base 21 is movably supported in the left-right direction orthogonal to the moving direction of the electric resistance welded pipe P via a, and a nut member 29b is provided at a substantially central portion in the front and rear directions.
And a screw rod 37a connected to the motor 37 provided on the holding table 21.
Is screwed through, and can be moved in the same direction as the left and right directions with respect to the holding base via the linear bearing 29a by the forward and reverse driving of the motor 37.

Hanging pieces 29c, 29c are provided on the lower surfaces of both ends of the suspension base 29, and pins 29d, 29d oriented parallel to the tube axis of the electric resistance welded pipe P are provided on the lower side surfaces thereof. The interlocking frame 30 is horizontally supported by engaging 29d with the shaft hole 30d of the interlocking frame 30.

The interlocking frame 30 is configured by laterally projecting L-shaped side frames 30b, 30b from both ends of a frame 30a parallel to the suspension base 29, and in holes 30d formed near both ends of the frame 30a, The pins 29d of the hanging pieces 29c, 29c of the suspension base 29 are engaged, the pins 29d are engaged with the shaft holes 30d, and the support bases are provided in the holes 30e, 30e formed at the lower ends of both side frames 30b, 30b. 31
The pin 31c of is engaged.

The support base 31 has support frames 32f and 32r extending downward from both ends of the horizontal frame 31a, and pins 31c projecting outward in the vicinity of the lower ends of the support frames 32f and 32r, respectively, and the lower ends of the support frames 32f and 32r. A pair of follow-up rollers 34f and 34r are axially supported so as to form a V shape on both sides of the part.

As shown in FIG. 2, a supporting base 41 for supporting the electric resistance welded pipe P at a substantially constant interval is provided below the supporting base 31, and the supporting base 41 has y as shown in FIGS. Axial movement means 42,
The x-axis direction moving means 45 and the rotating means 48 are attached respectively, and the rotating means 48 is provided with a plurality of left and right flaw detection heads 49.

Figure 4 is an enlarged front view according to line IV-IV of FIG. 2, FIG. 5 is an enlarged side view according to line V-V of FIG. 4, the copying mechanism 40
2 shows the detailed configuration of the.

The support base 41 is provided with sleeve portions 41 and 41r on both the left and right sides, and is formed to have a V shape as a whole when viewed from the front. The upper center is fixed to the support base 31 described above. Left of the support base 41,
A pair of flaw detection heads 49, 49 are provided on the right sleeves 41, 41r, respectively, and a normal direction (hereinafter referred to as y The y-axis direction moving means 42 for moving the flaw detection head 49 in the axial direction), the x-axis direction moving means 45 for moving the flaw detection head 49 in the tangential direction (hereinafter referred to as the x-axis direction), and the flaw detection heads 49 for the electric resistance welded pipe P Rotating means 48 for rotating about axes 48d, 48d parallel to the above is provided, and these constitute a copying mechanism 40 .

<Y-axis direction moving means 42> As shown in FIG. 4, the y-axis direction moving platen 42b is movable along a guide rail 42a (see FIG. 5) provided on the surface of the support base 41 and extending in the normal direction. Is provided, and this y-axis direction moving board 4
2b is connected to the motor My via the ball screw 42c, and the ball screw 42c is driven by the forward and reverse driving of the motor My.
The y-axis direction moving board 42b can be moved in the y-axis direction together with the x-axis direction moving means 45, the rotating means 48, and the flaw detection head 49 provided on the y-axis direction moving board 42b.

<X-axis direction moving means 45> The x-axis direction moving means 45 is movable along an x-axis direction extending guide rail 45a provided on the front side of the y-axis direction moving board 42b. And a motor Mx is connected to the x-axis direction moving plate 45b via a ball screw 45c, and the copying roller 46, provided with the x-axis direction moving plate 45b, by the forward and reverse driving of the motor Mx. It can be moved together with the rotating means 48 and the flaw detection head 49 in the x-axis direction.

On the front surface of the x-axis direction moving plate 45b, a support plate 46b is provided on a rail 46a extending in the y-axis direction so as to be movable in the y-axis direction, and a copying roller 46 is attached to an arm 46c extending from the support plate. A rod of an air cylinder 46d provided on the x-axis direction moving plate 45b is connected to the upper surface of the support plate 46b, and the copying roller 46 is connected to the electric resistance welded pipe P by driving the air cylinder 46d. The flaw detection head 49 is rotatably brought into contact with the surface of the electric resistance welded pipe P so as to be opposed to the surface of the electric resistance welded pipe P at a predetermined distance.

<Rotating means 48> An electric resistance welded pipe P protruding from the front surface of the support board 46b of the copying roller 46.
The timing pulley 48a having a shape in which a disk is partially cut out is axially supported by a shaft 48d parallel to the moving direction of the pulse motor Mr. The belt 48b is stretched around the timing pulley 48a, and the timing pulley 48a is rotated by the forward and reverse driving of the pulse motor Mr.

A flaw detection head 49 is fixed to the front surface of the timing pulley 48a via a mounting board 49a. When the pulse motor Mr is driven, the flaw detection head 49 rotates, and ultrasonic waves are incident on the surface of the electric resistance welded pipe P. The angle is adjusted.

The flaw detection head 49 is configured by providing a probe 49c in a cylindrical holder 49b, and jets water supplied from a water supply system (not shown) toward the surface of the electric resistance welded pipe P, and is formed by this. The ultrasonic wave transmitted from the probe 49c through the water film is propagated to the surface of the electric resistance welded pipe P, and the reflected ultrasonic wave from the seam portion S propagated through the same path is received.

Next, the operation of such a device of the present invention will be described.

By driving the motor 11 shown in FIG. 1 to rotate the ball screw 11a, the stopper 8 is moved and positioned according to the diameter of the electric resistance welded pipe P to be flaw-detected, and the lower limit of the elevating frame 4 is set.
The air cylinder 7 is driven to support the elevating frame 4 and the flaw detection head 49 supported by the elevating frame 4 above the moving area of the electric resistance welded pipe P and make them stand by.

In the process in which the electric resistance welded pipe P placed on the chain conveyor 3 moves under the ultrasonic flaw detection device 1, the air cylinder 7 is driven to move down the following mechanism 20, the copying mechanism 40 and the flaw detection head 49,
Left and right follower rollers 24f, 24r, circumferential follower rollers 34f, 3
4r is lowered in a manner to straddle the electric resistance welded pipe P, and
Through the y-axis direction moving means 42, the x-axis direction moving means 45, and the rotating means 48 of the copying mechanism 40, the flaw detection head 49 is opposed to the seam portion S of the electric resistance welded pipe P at a predetermined distance in the same direction and at a predetermined angle. Then, the copying roller 46 is brought into rolling contact with the surface of the electric resistance welded pipe P.

As a result, the probe 49c of the flaw detection head 49 faces the surface of the electric resistance welded pipe P at a predetermined angle with respect to its normal line. While forming a water film from the flaw detection head 49 toward the surface of the electric resistance welded pipe P, ultrasonic waves are transmitted from the probe 49c to start flaw detection.

<Upward and downward movement of ERW pipe P> During flaw detection, the load of the ultrasonic flaw detector 1 is in a state of being supported by the air cylinder 7 and the ERW pipe P, and within the regulation range of the stopper 8. Since the downward movement is allowed, in response to the upward and downward displacement of the electric resistance welded pipe P, the ultrasonic flaw detector 1 moves upward and downward by the elastic action of the air cylinder 7 and follows it. .

<Movement of ERW pipe P to the left and right> If the ERW pipe P is displaced in the left and right directions with the seam portion S facing upward, the ERW pipe P rolls over the ERW pipe P. As a result of each pair of follower rollers 24f, 24r being pressed being pushed leftward or rightward by the electric resistance welded pipe P, the holding table 21 is moved leftward or rightward with respect to the elevating frame 4 via the linear bearing 12. It is moved and the following rollers 34f, 34
r also moves in the same direction and follows the left and right movements of the electric resistance welded pipe P.

<Rotation of ERW pipe P> When the ERW pipe P rotates and the seam portion S thereof shifts in the circumferential direction, a seam portion sensor (not shown) detects this and the motor
The linear bearing 29
It is moved to the left or right direction orthogonal to the pipe axis of the electric resistance welded pipe P via a and 29a.

When the suspension base 29 is moved to the left or right with respect to the pipe axis of the electric resistance welded pipe P, the interlocking frame 3 pivotally supported by the suspension base 29 via the pin 29d.
0 is also moved in the same direction as suspension table 29. When the interlocking frame 30 is moved leftward or rightward, the support base 31 pivotally supported by the interlocking frame 30 also moves in the same direction via the pin 31c.

Since follower rollers 34f and 34r are axially supported by the support base 31, and the follower rollers 34f and 34r are rolling contact with each other while straddling the electric resistance welded pipe P, the lower part of the support base 31 is the follower roller 34f. left,
Restrained from rightward movement, the support base 31 is the interlocking frame 30
In contrast, it rotates around the pin 31c.

By the rotation of the support base 31, each flaw detection head 49 provided on the support base 31 is rotated to a position facing the seam portion S in a state of facing the peripheral surface of the electric resistance welded pipe P and follows the seam portion S. Becomes

<Changeover for changing wall thickness and pipe diameter> When there is a changeover for pipe diameter, at the same time as the flaw detection of the electric resistance welded pipe P that is currently being detected is completed, the air cylinder 7
Drive head, and detect head with tracking mechanism 20 and copying mechanism 40.
By moving 49 upward or downward, the new electric resistance welded pipe P is made to straddle the left and right direction following rollers 24f and 24r and the circumferential direction following rollers 34f and 34r.

Prior to this or in parallel with this, the y-axis direction moving means 42, the x-axis direction moving means 45, and the rotating means 48, which constitute the copying mechanism 40 , are driven to appropriately skip from the seam portion S in the circumferential direction. The flaw detection head 49 is positioned at a position separated by a distance and at an appropriate incident angle of ultrasonic waves.

〔effect〕

As described above, in the device of the present invention, the probe can be automatically positioned without using the calibration pipe when changing the tube diameter and wall thickness, the handling time of the calibration pipe can be shortened, and the incident angle The present invention has excellent effects such that the change can be automatically made, the applicable range is wide, and the cost of parts can be reduced.

[Brief description of drawings]

1 is a front view of the device of the present invention, FIG. 2 is a left side view of FIG. 1, FIG. 3 is an exploded perspective view of the main structure of the tracking mechanism, and FIG. 4 is a line IV-IV of FIG. FIG. 5 is an enlarged front view, FIG. 5 is an enlarged side view taken along the line VV of FIG. 4, and FIG. 6 is a perspective view showing a conventional flaw detector. 1 ... Ultrasonic flaw detector, 2 ... Frame, 3 ... Chain conveyor, 4 ... Lifting frame, 20 ... Follow-up mechanism, 21 ... Holding base, 24f, 24r ... Left and right follower rollers, 31 ...... Support base, 34f, 34r ...... Circular direction follow-up roller, 37 ...... Motor, 41
...... Support base, 42 ...... y-axis direction moving means, 42b …… y-axis direction moving board, 45 …… x-axis direction moving means, 45b …… x-axis direction moving board, 46 …… Copying roller, 48 …… Rotating means, 48d ...
… Axis, 49… flaw detection head, 49c… probe

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-57-500262 (JP, A) Actual Kaihei 2-37366 (JP, U) Actual public Sho-56-25414 (JP, Y2)

Claims (1)

[Claims] 1. An elevating frame (4) supported to be movable up and down with respect to a moving range of an electric resistance welded pipe, and left and right directions orthogonal to the moving direction of the electric resistance welded pipe on the elevating frame (4). And a holding table (21) equipped with follow-up rollers (24f, 24r) that are movably supported by the lower end and that roll on the lower end of the electric resistance welded pipe and follow the movement in the left, right, up, and down directions. A follower roller (34f) which is movably supported on the holding base (21) so as to be movable in the left and right directions of the electric resistance welded pipe, and which is in rolling contact with the support base (41) and the electric resistance welded pipe at the lower end and moves in the circumferential direction. A follower mechanism (20) consisting of a support base (31) provided with the support base (31), and a moving means provided in the support base (41) in a direction parallel to the tangent to the surface near both sides of the seam of the electric resistance welded pipe. (42), a moving means (45) in a direction parallel to the normal line, and a rotating means (48) for rotating about an axis parallel to the tube axis of the electric resistance welded pipe. And have mechanisms (40), an ultrasonic flaw detector of electric-resistance-welded pipe characterized in that it comprises at least a pair of contacts (49) which is supported via a 該倣 have mechanism (40).