JP6086692B2 - Metal pipe circumference measuring device - Google Patents

Description

  In the present invention, the metal plate is formed into a cylindrical shape with a plurality of rolls while rewinding the coil of the metal plate, and the outer peripheral length of the metal tube formed by abutting both ends in the width direction of the metal plate is reduced. The present invention relates to a circumference measuring apparatus for measuring.

A metal tube formed by butting both ends in the width direction of a metal plate that is rolled into a cylindrical shape, such as an electric resistance steel pipe, and welding the butted portion is one of the quality controls. It is usual to measure the outer peripheral length of the metal tube after welding.
When measuring the outer peripheral length of such a metal tube, for example, as described in Patent Document 1, surface waves such as ultrasonic waves are propagated in the circumferential direction of the metal plate to the outer peripheral surface of the metal tube. Measurement devices that measure the propagation time of the surface wave around the outer peripheral surface of the metal tube and measure the outer peripheral length of the metal tube from the relationship between the measured propagation time and the propagation speed of the known surface wave are widely known. ing.

However, the measuring device of the type as described in Patent Document 1 needs to propagate a surface wave on the outer circumferential surface of a cross section perpendicular to the circumferential direction of the metal tube, that is, the axial direction of the metal tube. Although it is suitable for measuring the outer peripheral length of a pipe, it is not suitable for measuring the outer peripheral length of a moving metal pipe during pipe making. That is, the measuring apparatus as disclosed in Patent Document 1 has a problem that the metal tube in the pipe making moves perpendicularly to the circumference measurement surface, but cannot follow the movement of the metal tube.
Therefore, when actually measuring the outer circumference of a metal pipe during pipe making, the worker can approach the metal pipe during pipe making and increase the outer circumference by wrapping a tape measure or wire around the metal pipe. The actual situation is measuring and it was very dangerous.

Japanese Patent Laid-Open No. 7-218242

By the way, it is considered to be most practical to use ultrasonic surface waves to measure the outer perimeter of metal pipes during pipe making safely, but to measure the outer perimeter using ultrasonic surface waves. In order to achieve this, ultrasonic waves must reliably propagate through the surface of the metal tube. To that end, the distance between the probe that transmits and receives ultrasonic waves and the surface of the metal tube must be kept constant. There is.
On the other hand, the metal pipe in pipe making has a round cross-sectional shape for the time being, but it is not an exact circle, and the straightness is not fixed, so the center is shifted up and down, left and right, or up and down. The shape is unstable and sometimes warps.
Therefore, it is difficult to maintain the distance between the surface of the metal tube whose shape is unstable, such as a metal tube during tube making, and the probe, and the transmission direction and reception direction of ultrasonic waves by the probe However, there is a possibility that it is not in a direction perpendicular to the original pass line but in an obliquely shifted direction, so that it is impossible to accurately measure the outer peripheral length.
Therefore, unless any measures are taken, it is impossible to continuously and accurately measure the outer peripheral length of the metal pipe during pipe making.

  The technical problem of the present invention is to propagate the outer peripheral length of a metal tube in the pipe making formed by abutting both ends in the width direction of a metal plate formed into a cylindrical shape in the circumferential direction of the metal tube. An object of the present invention is to provide a metal tube circumference measuring device that can measure continuously and accurately using the surface wave that has been made, and that can be measured safely.

In order to solve the above-mentioned problems, the circumference measuring apparatus for a metal tube according to the present invention forms a metal plate into a cylindrical shape with a plurality of rolls while rewinding a coil of the metal plate, and both ends of the metal plate in the width direction. A peripheral length measuring device that measures the outer peripheral length of a metal tube formed by abutting parts using a surface wave propagated in the circumferential direction of the metal tube, the outer peripheral surface of the metal tube being formed Are disposed on the upper side or the lower side of the metal tube, and the transmitter and the receiver are disposed on the upper side or the lower side of the metal tube. And a holder that holds the transmitter and the receiver along the circumferential direction of the outer peripheral surface of the metal tube, and the holder from the outer peripheral surface of the metal tube of the transmitter and receiver. Creating guide rollers that maintain a constant distance, and transmitter and receiver A circumferential follow-up mechanism that follows a horizontal misalignment of the metal tube, and the holding member has a pair of arm members that are bifurcated, and the transmitter and receiver are provided on one arm member. At least a transmitter is attached, and at least a receiver is attached to the other arm member, and the guide roller is disposed on the tip side of each arm member of the holding member, The metal pipe can be rotated in the pass line direction of the metal pipe while being always in contact with the outer peripheral surface of the metal pipe, and the circumferential follow-up mechanism tilts the holding member along the circumferential direction of the metal pipe during pipe making. The holding member is configured such that the opening between the pair of arm members can be adjusted, and the interval between the transmitter and the receiver can be changed according to the outer diameter of the metal tube. When measuring the circumference of a metal pipe It is characterized in that it is possible secure the opening.

In addition, another metal pipe circumference measuring apparatus of the present invention forms a metal plate into a cylindrical shape with a plurality of rolls while rewinding a coil of the metal plate, and abuts both ends in the width direction of the metal plate. A circumferential length measuring device that measures the outer circumferential length of a metal tube formed by using a surface wave propagated in the circumferential direction of the metal tube, the outer circumferential surface of the metal tube being piped A transmitter for transmitting a surface wave in the circumferential direction, a receiver for receiving a surface wave from the transmitter, and an upper side or a lower side of the metal tube. The transmitter and the receiver are connected to the metal tube. A holder that holds the outer peripheral surface of the metal tube along the circumferential direction, and the holder has a fixed distance between the transmitter and the receiver attached to the outer peripheral surface of the metal tube of the transmitter and the receiver. The guide roller that is held in the horizontal direction of the metal pipe that is forming the transmitter and receiver The holding member has a pair of arm members bifurcated, and the transmitter and receiver are attached only to one arm member. The guide roller is disposed on the tip side of each arm member of the holding member, and can freely rotate in the pass line direction of the metal tube while being always in contact with the outer peripheral surface of the metal tube during pipe making. The circumferential follow-up mechanism is configured to tilt the holding member along the circumferential direction of the metal tube during pipe making, and the holding member can freely adjust the opening degree between the pair of arm members. The distance between the transmitter and the receiver can be changed according to the outer diameter of the metal tube, and the opening degree can be fixed when measuring the circumference of the metal tube. To do.

  In these cases, the circumferential follow-up mechanism includes a rotary shaft provided on the proximal end side of the pair of arm members in the holding member and extending in the pass line direction of the metal tube, and each arm member in the radial direction of the metal tube. And an elastic member that elastically urges the pair of arm members to tilt the pair of arm members around the rotation axis along the circumferential direction of the metal pipe in the pipe making process.

  Further, in the present invention, the holder moves the holding member in synchronization with the vertical movement of the metal pipe during pipe making, so that the transmitter and receiver are connected to the metal pipe during pipe making. A radial follower mechanism that follows a vertical misalignment can be provided.

  In this case, the radial follow-up mechanism may include an elastic member that elastically biases the entire holding member in the radial direction of the metal tube.

  Further, in the present invention, when the metal tube in the pipe making is inclined in the vertical direction, the holder tilts the holding member so as to follow the vertical inclination of the metal tube, and It is preferable that the receiver is provided with an axial direction tracking mechanism that inclines in a direction along the axial direction of the metal tube in pipe making and follows the direction in which the transmission and reception of surface waves are performed in the circumferential direction of the metal tube. .

In this case, the axial direction follow-up mechanism is provided on the first base portion to which the base end sides of the pair of arm members are coupled and the first base portion, and is orthogonal to the pass line direction of the metal tube. A rotation base extending in the horizontal direction; a second base portion including a bearing portion rotatably supported around the rotation shaft about the rotation shaft; a first base portion; a second base portion; A first base that is provided between the base and the elastic member that elastically biases the first base in the radial direction of the metal tube. By tilting the portion, the entire holding member can be tilted in the direction along the axial direction of the metal tube.
Alternatively, the axial direction follow-up mechanism includes a point at which an extension line extending in the radial direction of the metal tube from the tip of each arm member and the outer peripheral surface of the metal tube intersect with each other on each tip side of the pair of arm members. A rotating shaft extending in parallel with a tangent line as a contact point, and connected to each arm member via the rotating shaft, and at least one of a transmitter and a receiver is attached, and is rotatable around the axis of the rotating shaft. A tilting base part, and an elastic member provided between the tilting base part and the arm member for elastically biasing the tilting base part in the radial direction of the metal tube, The transmitter and the receiver can be inclined in the direction along the axial direction of the metal tube in the tube by tilting the tilting table portion as the center.

According to the circumference measuring apparatus of the metal pipe of the present invention, the circumferential follow-up mechanism appropriately follows the holding member to which the transmitter and the receiver are attached to the horizontal misalignment of the metal pipe during pipe making. Therefore, it is possible to appropriately follow the transmitter and the receiver in accordance with the horizontal movement of the metal tube while keeping the distance between them. In addition, the guide roller attached to the distal end side of each arm member of the holding member is always in contact with the outer peripheral surface of the metal tube even when the circumferential follow-up mechanism is functioning. Since the distance between the child and the outer peripheral surface of the metal tube is kept constant, the distance between the transmitter and the receiver and the outer peripheral surface of the metal tube can be stably held at an optimum distance.
As a result, the transmitter and the receiver can always be held at an appropriate circumference measurement position, so that the circumference of the metal tube during pipe making can be continuously and accurately measured. Moreover, unlike the conventional case, it is not necessary for the worker to measure the outer peripheral length of the metal tube close to the metal tube being formed, and the outer peripheral length of the metal tube being formed can be measured safely and stably. It becomes.
Moreover, since the opening degree of the arm member of the holding member can be adjusted and the opening degree can be fixed at the time of circumference measurement, the outer circumference length can be measured according to the arbitrary outer diameter of the metal pipe to be measured for the outer circumference length. .

  In addition, when the holder is provided with a radial direction follower mechanism, the holding member can be moved in synchronization with the vertical movement of the metal tube during pipe making. It is possible to follow the vertical misalignment of the metal pipe during pipe making. Thereby, the outer peripheral length of the metal pipe during pipe making can be measured more accurately.

Further, when the holder is provided with an axial direction follow-up mechanism, the holding member is tilted along the vertical inclination of the metal tube, so that the transmitter and the receiver are connected to the axis of the metal tube in the tube forming process. It can be inclined in a direction along the direction. This makes it possible to follow the direction in which the surface wave is transmitted and received by the transmitter and the receiver in the circumferential direction of the metal tube, so that the outer peripheral length of the metal tube during pipe making can be measured more accurately. Can be done .

It is a front view showing typically a 1st embodiment of a circumference measurement device of a metal pipe concerning the present invention. It is the same side view. It is the same top view. It is a front view which shows typically the state which the circumferential direction tracking mechanism which concerns on 1st Embodiment is functioning. It is explanatory drawing which shows typically the state which is measuring the outer periphery length of a metal tube using the circumference measurement apparatus of the metal tube which concerns on this invention. It is explanatory drawing which shows typically the state which is performing the measurement different from FIG. FIG. 3 is a front view schematically showing a second embodiment of the metal pipe circumference measuring apparatus according to the present invention. It is the same side view. It is a side view which shows typically the state in which the axial direction tracking mechanism which concerns on 2nd Embodiment is functioning. It is a front view which shows typically the state which the radial direction tracking mechanism which concerns on 2nd Embodiment is functioning. It is a front view showing typically a 3rd embodiment of a circumference measurement device of a metal pipe concerning the present invention. It is the same side view. It is the same top view. It is a side view which shows typically the state in which the axial direction tracking mechanism which concerns on 3rd Embodiment is functioning. It is a front view which shows typically 4th Embodiment of the circumference measuring apparatus of the metal pipe which concerns on this invention. It is the same top view. It is explanatory drawing which shows typically the state which is measuring the outer periphery length of a metal tube using the circumference measurement apparatus of the metal tube which concerns on 4th Embodiment.

Hereinafter, the metal pipe circumference measuring apparatus of the present invention will be described in detail.
The circumferential length measuring device of the present invention is configured such that the outer circumferential length of a metal pipe such as a steel pipe formed by abutting both ends in the width direction of a metal plate such as a steel sheet rolled into a cylindrical shape is the circumference of the metal pipe. It is measured using surface waves propagated in the direction.

1 to 3 show a first embodiment of a metal pipe circumference measuring apparatus according to the present invention. The circumference measuring apparatus according to the first embodiment is formed on a pass line. It has a transmitter 2 that transmits surface waves to the outer surface of the metal tube 1 and a receiver 3 that receives surface waves from the transmitter 2.
Furthermore, a holder 4A is provided below the pass line of the metal tube 1 to be formed, and holds the transmitter 2 and receiver 3 along the circumferential direction of the outer peripheral surface of the metal tube 1.
In FIG. 1, the transmitter 2 and the receiver 3 (strictly speaking, probes 17 and 18 described later having the functions of both the transmitter 2 and the receiver 3) are provided as auxiliary guide rollers 24 described later. , 25, so it is not represented.

The transmitter 2 has a predetermined emission angle with respect to the outer peripheral surface of the metal tube 1 during pipe making (specifically, an angle between the propagation direction and the emission direction to the metal tube with respect to the surface of the metal tube). The surface wave such as an ultrasonic wave is emitted and transmitted at an obtuse angle, and the surface wave is propagated in a specific direction on the outer peripheral surface of the metal tube 1.
On the other hand, the receiver 3 transmits a surface wave transmitted from the transmitter 2 and propagated through the outer peripheral surface of the metal tube 1 to a predetermined incident angle (specifically, the propagation direction and the metal tube with respect to the surface of the metal tube). (The angle at which the angle from the incident direction to the light is an obtuse angle) is incident on the receiver 3 for reception.
And the measurement of the outer peripheral length of the metal tube 1 measures the propagation time of the surface wave from the transmitter 2 to the receiver 3, and the surface wave specified by the propagation time and the material of the metal tube 1. Based on the known propagation velocity, the calculation is performed by a calculation means such as an electronic computer (not shown).
The transmitter 2 and the receiver 3 are not in contact with the metal tube 1 at all times, and the transmitter 2 and the receiver 3 transmit the surface wave by the transmitter 2 and receive the surface wave by the receiver 3. This is performed through a medium (not shown) such as water or oil that is constantly supplied to the gap between the outer peripheral surface of the metal tube and the surface of the metal tube.

On the other hand, the holder 4A includes a holding member 5 to which the transmitter 2 and the receiver 3 are attached, and a guide roller for maintaining a constant distance from the outer peripheral surface of the metal tube 1 of the transmitter 2 and the receiver 3. 6 and 7 and a circumferential follow-up mechanism 8 for causing the holding member 5 to follow the horizontal misalignment of the metal pipe 1 during pipe making.
The holding member 5 includes a pair of arm members 9 and 10 that are bifurcated toward the upper side, a base portion 11 that is provided below the pair of arm members 9 and 10, and the pair of arms. A connecting portion 12 that connects the members 9 and 10 and the base portion 11 is provided.

Each of the pair of arm members 9 and 10 is formed in a substantially L shape in a front view and a substantially U shape in a plan view as a whole.
Specifically, each arm member 9, 10 includes a pair of support portions 13, 13, 14, 14 formed in a column shape extending in parallel to each other in a direction perpendicular to the pass line direction of the metal tube 1, and Arm main body portions 15 and 16 are provided on the distal end sides of the pair of support portions 13, 13, 14, 14 so as to bridge between the support portions 13, 13, 14, 14.
Probes 17 and 18 having the functions of both the transmitter 2 and the receiver 3 are disposed on the distal ends of the arm main body portions 15 and 16 via mounting base portions 22 and 23 described later. The proximal end sides of the pair of support portions 13, 13, 14, 14 are connected to the connecting portion 12, respectively.
Further, between the support portions 13 and 13 of the one arm member 9 and the support portions 14 and 14 of the other arm member 10, interposition members 19 and 19 to be described later are respectively disposed. Further, a plurality of holes for adjusting the opening between the arms 9 and 10, which will be described later, and fixing the opening are formed in the pair of support portions 13, 13, 14, and 14, respectively, at predetermined positions. ing.

In addition to the original function of holding the probes 17 and 18, the pair of arm members 9 and 10 in this embodiment has a probe of one arm member and a probe of the other arm member. It also has a function of keeping the distance between the children constant. As a result, when the outer peripheral length of the metal tube 1 is measured, that is, during the formation of the metal tube 1, the opening between the pair of arm members is fixed, and the distance between the probes is fixedly maintained. It has come to be.
In addition, the probes 17 and 18 attached to the pair of arm members 9 and 10 are normally used, that is, when the metal tube 1 is linearly formed without deviating from the pass line, the transmitter 2 is used. The surface wave can be transmitted from the circumferential direction of the outer circumferential surface of the metal tube 1, that is, the circumferential direction of the outer circumferential surface in the cross section orthogonal to the pass line, and the surface wave propagated in the circumferential direction is received by the receiver 3. Are set to receive directions.
The measurement of the outer peripheral length of the metal tube by each of the probes 17 and 18 is performed, for example, when a surface wave is transmitted from the transmitter 2 of the probe 17 in one arm member 8, in the other arm member 9. This is performed by being received by the receiver 3 of the probe 18.

The interposition members 19 and 19 are formed in a plate shape as a whole, and a pair of a main body 19a through which a rotating shaft 29 described later passes and a Y-shaped branch provided on one end side of the main body 19a. Projecting portions 19b, 19b and a base portion 19c provided on the other end side of the main body portion 19a.
The main body portion 19a is a portion sandwiched between the pair of arm members 9 and 10, and the pair of projecting portions 19b and 19b is used for adjusting the opening degree between the arms 9 and 10 described below and opening the same. A plurality of holes used for adjusting the degree of opening and fixing the degree of opening are respectively formed at predetermined positions.
Further, the base portion 19c constitutes a part of a circumferential follow-up mechanism 8 described later, and each arm member 9 and 10 is elastically elastic in the radial direction of the metal tube while maintaining a set opening degree. One end sides of the elastic members 30 and 31 for energizing circumferential follow-up are respectively connected.
In this embodiment, the interposition members 19, 19 are connected to each other by a connection member 19d disposed between the base portions 19c, 19c, and the interposition members 19, 19 are integrated as a whole. It becomes the composition which became. In the case of this embodiment, the connecting member 19d is formed in a flat plate shape having the same width and the same thickness (height) as the base portion 19c of each interposed member 19, and both end portions in the longitudinal direction are The base portions 19c of the connecting members 19 are fixed to the opposing surfaces. The connecting member 19d is fixed to the base portions 19c and 19c so that the plate surface thereof is perpendicular to the connecting surface of the base portion 19c (the surface where the base portions 19c face each other). The plate surfaces are maintained parallel to each other.

Further, the pair of arm members 9 and 10 can freely adjust the opening degree between these arm members 9 and 10, and the distance between the probes 17 and 18 of the arm members 9 and 10, that is, The distance between the transmitter 2 of one arm member and the receiver 3 of the other arm member can be changed. The opening between the arm members 9 and 10 can be fixed when measuring the circumference of the metal tube, and the adjusted opening is not changed during the circumference measurement. The distance between the ten probes 17 and 18 is kept constant.
Thereby, according to the outer diameter of the metal pipe 1 used as the measuring object of outer periphery length, the position of the circumferential direction with respect to the outer peripheral surface of the metal tube 1 of the transmitter 2 and the receiver 3 can be adjusted previously, and the transmitter 2 While the transmission angle of the surface wave with respect to the outer peripheral surface of the metal tube 1 and the reception angle of the receiver 3 can be set to an appropriate angle according to the outer diameter of the metal tube 1, It is possible to stably maintain the set transmission angle of the transmitter and the reception angle of the receiver.
In this embodiment, a plurality of holes provided at predetermined positions of the support portions 13, 13, 14, and 14 of the pair of arm members 9 and 10, and predetermined positions of the protruding portions 19b and 19b of the interposition member 19 are provided. The opening between the arm members 9 and 10 can be adjusted and the opening can be fixed by using a plurality of holes provided in the arm and pins inserted through the holes.
Here, the plurality of holes of the support portions 13, 13, 14, 14 and the plurality of holes of the projecting portions 19 b, 19 b have an opening degree between the arm members 9, 10 according to the outer diameter of the metal tube 1. They are arranged in a positional relationship that can be adjusted in stages. And the opening degree between the arm members 9 and 10 can be changed in steps and fixed by changing the position where the pin is inserted.
In addition, as a configuration for adjusting and fixing the opening degree of these arm members 9 and 10, for example, using bolts and nuts, the arm members 9 and 10 are crimped to each other by tightening them. Arbitrary structures can be used, such as fixing the relative position.

The arm body portions 15 and 16 of the pair of arm members 9 and 10 rise substantially perpendicularly from the tips of the pair of support portions 13, 13, 14, and 14. 15 and 16, recessed portions 20 and 21 that open in the distal direction, and the mounting base portions 22 and 23 that are housed in the recessed portions 20 and 21 and to which the probes 17 and 18 are mounted, respectively. It has become.
Further, a plurality of auxiliary guide rollers 24 and 25 arranged in parallel in the pass line direction of the metal tube 1 so as to sandwich the mounting base portions 22 and 23 at the front end side of each opening edge of the concave portions 20 and 21. Each is arranged.

The mounting base portions 22 and 23 are plate-like or rectangular parallelepiped long in the pass line direction of the metal tube 1, and the probe 17, 18 are arranged respectively. Further, the guide rollers 6 and 7 described above are attached to both ends of the metal tube 1 in the pass line direction so as to sandwich the probes 17 and 18, respectively.
Furthermore, between the lower end side of these mounting base parts 22 and 23 and the recessed bottom part of the recessed parts 20 and 21, each mounting base part 22 and 23 is elastic toward the direction of the metal tube 1 to make a pipe. Elastic members 26 and 27 for the mounting base portion for biasing are respectively provided. The elastic members 26 and 27 for the mounting bases are respectively disposed in the portions directly below the guide rollers 6 and 7 on the lower end side of the mounting bases. For example, springs or the like are used.
Accordingly, the guide rollers 6 and 7 are always in elastic contact with the surface of the metal tube and rotate along the outer peripheral surface of the metal tube 1, and the mounting base portions 22 and 23 are connected to the guide rollers. Since the entire mounting base moves in the radial direction of the metal tube in synchronism with the movements of 6 and 7, the distance from the outer peripheral surface of the probe 17 and 18 to the metal tube 1 is kept constant. Become.

The auxiliary guide rollers 24 and 25 are configured to be rotatable in the pass line direction of the metal tube 1 in a state in which a part of the outer peripheral surface protrudes to the metal tube side from the probes 17 and 18. It is always in contact with the outer peripheral surface of the metal pipe 1 during pipe making.
In the state where the auxiliary guide rollers 24 and 25 are in contact with the outer peripheral surface of the metal tube 1, the mounting base portions 22 and 23 are depressed by the guide rollers 6 and 7 being pushed by the metal tube 1. 20 and 21 are elastically pushed in a direction opposite to the direction of the metal tube 1.

The base portion 11 is formed in a flat plate shape, and a pair of portions constituting a part of the connecting portion 12 is formed in the center portion in the width direction (left and right direction of the pass line of the metal tube 1) on the upper surface side. Bearing portions 28 and 28 are erected. In addition, the base part 11 in this embodiment is fixedly mounted on a stable floor surface or the like.
The connecting portion 12 includes the pair of bearing portions 28 and 28 and a rotating shaft 29 that is disposed on the base end side of the pair of arm members 9 and 10 and extends in the pass line direction of the metal tube 1. It is configured.
The rotating shaft 29 connects the pair of arm members 9, 10, specifically the base end sides of the pair of support portions 13, 13, 14, 14 and the interposition members 19, 19 in the metal line pass line direction. Has penetrated. Then, both end sides in the axial direction protruding from the pair of arm members 9 and 10 are rotatably supported by the pair of bearing portions 28 and 28, respectively. As a result, the pair of arm members 9 and 10 can be tilted about the rotation shaft 29 around the rotation shaft 29.
The connecting portion 12 is a part of the configuration of the holding member 5, but also serves as a part of the configuration of the circumferential follow-up mechanism, as will be described later. It also functions when following the horizontal misalignment of the tube 1.

As described above, each of the guide rollers 6 and 7 includes a pair of arm members 9 and 10 of the holding member 5, more specifically, a mounting base portion disposed on the distal end side of the arm main body portions 15 and 16. 22 and 23 are arranged on the upper end side.
These guide rollers 6 and 7 are rotatable in the direction of the pass line of the metal tube 1, and the probe 17, They are arranged so as to sandwich 18.
Each guide roller 6, 7 protrudes in the direction toward the metal tube 1 from the probes 17, 18, and always contacts the outer peripheral surface of the metal tube 1 during the pipe making while rotating. A gap is formed between the probes 17 and 18 and the metal tube 1 so that the distance of the probes 17 and 18 from the outer peripheral surface of the metal tube 1 is always kept constant.
Note that, as described above, a medium such as water is constantly supplied to the gaps between the probes 17 and 18, that is, the transmitter 2 and the receiver 3 and the outer peripheral surface of the metal tube 1.

The circumferential follow-up mechanism 8 tilts the pair of arm members 9 and 10 of the holding member 5 so as to follow the circumferential direction of the metal tube 1 during pipe making.
Depending on the shape after roll forming, the metal tube in pipe making may move in the left-right direction of the pass line and may be misaligned in the horizontal direction. When measuring the length, there is a possibility that the metal tube is separated from the transmitter and receiver. Then, the transmitting position and direction of the surface wave with respect to the outer surface of the metal tube by the transmitter, the receiving position and direction of the surface wave by the receiver deviate from the proper position and direction, and the accurate position of the metal tube in the pipe making The outer circumference cannot be measured. In particular, it is considered that the horizontal misalignment is most likely to occur during the production of a metal tube.
Therefore, in the present invention, the holding member is tilted along the circumferential direction of the metal tube in the pipe making by the circumferential direction tracking mechanism, and the probe, that is, the transmitter and the receiver are moved to the metal pipe. It is made to follow the horizontal misalignment of the tube.

Specifically, the circumferential follow-up mechanism 8 includes the connecting portion 12 constituting a part of the holding member 5, that is, the pair of bearing portions 28 and 28, the rotating shaft 29, and the arm members 9 and 10. It has elastic members 30 and 31 for following in the circumferential direction, which elastically urge each in the radial direction of the metal tube.
In this embodiment, the elastic members 30 and 31 for circumferential follow-up are attached to the base portion 19c of the interposition member 19 on one end side and to the base portion 11 on the other end side, respectively. Between the base portion 19c and the base portion 11, the arm members 9 and 10 are respectively urged in the radial direction of the metal tube while the opening degree is kept constant. Note that a spring or the like can be used as the elastic member.
As a result, the pair of arm members 9 and 10 can be tilted in the left-right direction of the pass line of the metal tube 1 with the opening degree being constant with the rotation axis 29 of the connecting portion 12 as the center, and the circumferential follow-up is performed. The arm members 9 and 10 are elastically pressed in the radial direction of the metal tube by the elastic members 30 and 31 so that the arm members 9 and 10 are always pressed against the metal tube.

FIG. 4 shows a state where the circumferential tracking mechanism 8 functions and the pair of arm members 9 and 10 are tilted. A broken line indicates a state before the axial direction tracking mechanism 8 functions.
When the metal pipe 1 in the pipe making is displaced in the horizontal direction (left and right direction of the pass line), an arm member (arm member 9 in FIG. 4) positioned in the displacement direction of the metal pipe 1 The outer peripheral surface is pressed through the guide roller (guide roller 6 in FIG. 4) and the auxiliary guide roller (auxiliary guide roller 24 in FIG. 4).
On the other hand, in accordance with the movement of the pair of arm members 9 and 10, the circumferential follow-up elastic member (the elastic member 30 in FIG. 4) located on the displacement direction side of the metal tube 1 is reduced and is located on the opposite side. When the elastic member (the elastic member 31 in FIG. 4) is expanded, the arm members 9 and 10 are elastically pressed against the metal tube 1 via the guide rollers 6 and 7 and the auxiliary guide rollers 24 and 25. The pair of arm members 9 and 10 are tilted while maintaining the above.
Thus, by the action of the circumferential follow-up mechanism 8, the pair of arm members 9 and 10 that are a part of the holding member 5 are kept in the horizontal direction of the metal pipe 1 during pipe making while maintaining the opening degree. It can be tilted according to the movement of. Thereby, it becomes possible to always follow these pair of arm members 9, 10 along the circumferential direction of the metal tube 1.
As a result, the transmitter 2 and the receiver 3 of the probes 17 and 18 can always follow the horizontal misalignment of the metal tube 1 during pipe making.

The circumference measurement apparatus for metal pipes having the above-described configuration can measure the circumference of a so-called open pipe immediately before welding the butt part, as well as the metal pipe after welding the butt part. it can.
When measuring the outer perimeter of a metal pipe during pipe making using this perimeter measuring device, when measuring the outer perimeter of a normal metal pipe welded with a butt portion, The circumference measuring device is arranged at a position after welding of the butt portion. On the other hand, when measuring the outer peripheral diameter of the open pipe, this peripheral length measuring device is arranged at a position on the metal pipe pass line immediately before welding the butted portion of the open pipe.
Then, the opening between the pair of arm members 9 and 10 of the holding member 5 is adjusted according to the outer diameter of the metal pipe or open pipe to be measured, and the transmitter 2 and receiver 3 of the probes 17 and 18 are adjusted. The peripheral position of the metal tube is set to an appropriate position in the circumferential direction, and a metal tube or an open pipe is formed on it, and a surface wave is transmitted from the transmitter of the probe of one arm member, The signal is received by the probe receiver of the other arm member.

FIG. 5 shows an example of measuring the outer peripheral length of the metal tube 1 after welding the butt portion 1a. In FIG. 5, the dashed arrow indicates the propagation direction of the surface wave.
In this case, the surface wave transmitted from the probe 18 (which functions as the transmitter 2 in this case) in one arm member 10 passes through the welded butt portion 1a and passes through the other arm. Received by the probe 17 in the member 9 (in this case, functioning as the receiver 3), the propagation time is measured.
Then, the propagation distance of the surface wave is calculated from the propagation time and the velocity of the known surface wave, and the outer peripheral length of the metal tube 1 is calculated by adding the distances of the probes 17 and 18 known in advance. Can do.
In the case shown in FIG. 5, one probe 18 functions as the transmitter 2 and the other probe 17 functions as the receiver 3. However, the probe 17 serves as the transmitter and the probe 18. May function as a receiver. In this case, the propagation direction of the surface wave is opposite to that in FIG.

Moreover, FIG. 6 has shown the case where the outer periphery length of the metal pipe 1 (open pipe) before welding the said butt | matching part 1a is measured. In FIG. 6, the broken arrow indicates the propagation direction of the surface wave toward the abutting portion 1 a, and the two-dot chain arrow indicates the propagation direction of the surface wave reflected by the abutting portion 1 a.
In this case, a surface wave is transmitted from the probe 17 of one arm member 9 (at this time, the probe 17 functions as the transmitter 2), and the transmitted surface wave is welded. Reflected by the non-matching portion 1a and received by the same probe 17 (at this time, the probe 17 functions as the receiver 3), and the propagation time of the surface wave is measured. On the other hand, a surface wave is transmitted from the probe 18 of the other arm member 10 (at this time, the probe 18 functions as the transmitter 2), and the transmitted surface wave is not welded. The light is reflected by the butting unit 1a and is received by the same probe 18 (at this time, the probe 18 functions as the receiver 3).
Then, based on the propagation times measured by the probes 17 and 18 from the propagation times and the known surface wave velocities, the propagation distances L1 and L2 of the respective surface waves are calculated and known in advance. By adding the distance L3 between the probes 17 and 18, the outer peripheral length of the metal tube 1 can be calculated.

Here, when measuring the outer peripheral length of the metal pipe 1 in the pipe making, the metal pipe 1 in the pipe making may be displaced in the horizontal direction (left-right direction) from the pass line depending on the shape of the metal pipe.
At this time, the holder 4A holds the spacing between the probes 17 and 18 of the pair of arm members 9 and 10 constant, and the outer peripheral surface of the metal tube 1 of the transmitter 2 and receiver 3 Guide rollers 6 and 7 and auxiliary guide rollers 24 and 25 that maintain a constant distance from each other, and a circumferential follow-up mechanism 8 that follows the horizontal misalignment of the metal tube 1 during pipe making. While keeping the distance between the probes 17 and 18, the probes 17 and 18 are appropriately followed in accordance with the horizontal movement of the metal tube 1.
Thereby, since the transmitter 2 and the receiver 3 of each probe 17 and 18 are always held at an appropriate circumference measurement position, the measurement of the circumference of the metal tube 1 during pipe making is continuously performed. Can be done accurately.
Moreover, unlike the conventional case, it is not necessary for the worker to measure the outer peripheral length of the metal tube close to the metal tube being formed, and the outer peripheral length of the metal tube being formed can be measured safely and stably. It becomes.

In the first embodiment, as a mechanism for causing the transmitter 2 and the receiver 3 to follow the metal tube 1 during tube forming, the holder 4A is provided with a holding member 5 in the circumferential direction of the metal tube 1 during tube forming. The circumferential follow-up mechanism 8 is provided to cause the transmitter 2 and the receiver 3 to follow the horizontal misalignment of the metal tube 1 during pipe making.
However, in the second embodiment described below, the holder follows the radial follow-up mechanism, and the radial follow-up causes the transmitter and receiver to follow the vertical misalignment of the metal pipe during pipe making. And an axial direction follower mechanism that causes the transmitter and receiver to incline in a direction along the axial direction of the metal tube during pipe making and follows the direction in which the transmission and reception of surface waves are performed in the circumferential direction of the metal tube; Is further provided.

7 and 8 show a second embodiment of the metal pipe circumference measuring apparatus of the present invention.
In the circumference measuring apparatus according to the second embodiment, in addition to the configuration of the circumference measuring apparatus according to the first embodiment, the holder 4B has the upper and lower sides of the metal pipe 1 during pipe making of the holding member 5. A radial follower mechanism 35 is provided to move the transmitter 2 and the receiver 3 in synchronization with the movement of the direction so as to follow the vertical misalignment of the metal tube 1 during pipe making.
Further, when the metal pipe 1 in the pipe making is inclined in the vertical direction, the holding member 5 is tilted so as to follow the vertical tilt of the metal pipe 1, and the transmitter 2 and the receiver 3 are manufactured. By tilting the metal tube 1 in the direction along the axial direction of the metal tube 1, an axial direction tracking mechanism 36 is provided to follow the direction in which surface waves are transmitted and received in the circumferential direction of the metal tube.
Note that the configurations of the transmitter, receiver, and holding member (except for the first base portion 37 described later) constituting the probe are substantially the same as those of the first embodiment. In order to achieve the same operational effects, the same reference numerals are attached to the drawings, and detailed description thereof is omitted. Further, in FIG. 7, the transmitter 2 and the receiver 3 (strictly speaking, probes 17 and 18 described later having functions of both the transmitter 2 and the receiver 3) are provided as auxiliary guide rollers 24 and 25. It is not represented because it is hidden by.

The axial direction follow-up mechanism 36 functions when the axis of the metal tube 1 during pipe forming is inclined upward in the pass line direction or when the axis is inclined downward. is there.
Depending on the shape after roll forming, the metal tube during pipe forming may move on the pass line so that its axis is inclined in the vertical direction and the metal tube undulates up and down. When measuring the outer peripheral length of a metal tube in pipe making having such a shape, the direction of surface wave transmission with respect to the outer surface of the metal tube by the transmitter and the direction of reception of the surface wave by the receiver are determined as follows. The direction is shifted from the circumferential direction. Then, since the surface wave does not propagate correctly in the circumferential direction of the metal tube, there is a very high possibility that a measurement error will occur, and the exact outer circumference of the metal tube during pipe making cannot be measured.
Therefore, in this embodiment, and in third and fourth embodiments to be described later, the holding member is tilted along the vertical inclination of the metal tube by the axial direction follow-up mechanism. The probe, that is, the transmitter and the receiver are tilted in the direction along the axial direction of the metal tube during pipe making so that the surface wave is transmitted and received in the circumferential direction of the metal tube. ing.

Specifically, the axial direction follow-up mechanism 36 is a first base that is a part corresponding to the base part 11 to which the base end sides of the pair of arm members 9 and 10 are connected in the first embodiment. A portion 37 is provided. Further, a rotary shaft 38 for tracking in the axial direction provided in the first base portion 37 and extending in the horizontal direction perpendicular to the pass line direction of the metal tube 1, and the rotary shaft 38 around the rotary shaft 38. And a second base portion 40 having a pair of bearing portions 39 and 39 that are rotatably supported around the axis.
Further, it is provided between the first base part 37 and the second base part 40, and is adapted to follow the axial direction for elastically urging the first base part 37 in the radial direction of the metal tube. The elastic member 41 is provided.

The rotating shaft 38 for following the axial direction is arranged on an axis passing through the first base portion 37 directly below the probes 17 and 18, and both end sides thereof are separated from the first base portion 37. It protrudes.
The second base portion 40 includes the above-described pair of bearing portions 39 and 39 that rotatably support both projecting end sides of the rotary shaft 38 on the upper surface side, whereby the first base portion 40 is provided. The base portion 37 can be tilted about the rotation shaft 38 around the rotation shaft 38.
In addition, the elastic member 41 for tracking in the axial direction includes the rotating shaft 38 and a pair of bearing portions 39 in a space between the lower surface of the first base portion 37 and the upper surface of the second base portion 40. , 39, for example, at positions close to both ends in the pass line direction, so that the first base 37 is always elastically biased in the radial direction of the metal tube. It has become. As the elastic member 41, a spring or the like is used.
Thereby, the axial direction follow-up mechanism 36 makes the first base portion 37 tiltable in the vertical direction around the rotation shaft 38, and the elastic member 41 causes the first base portion 37 to move. By elastically urging the metal tube in the radial direction, the holding member 5, particularly the pair of arm members 9, 10 is constantly pressed along the axial direction of the metal tube.

FIG. 9 shows a state in which the holding member 5 is tilted with the axial direction follow-up mechanism 36 functioning. In addition, the broken line in FIG. 9 has shown the state before the axial direction tracking mechanism 36 functions.
For example, when the metal pipe 1 during pipe forming is inclined downward in the pipe forming direction due to, for example, a lower groove generated during roll forming, the metal pipe 1 causes a pair of arm members. 9 and 10 are pushed through guide rollers 6 and 7 and auxiliary guide rollers 24 and 25 located on the front side of the pass line, respectively.
On the other hand, in accordance with the movement of the pair of arm members 9 and 10, the elastic member 41 for tracking in the axial direction positioned on the front side of the pass line is elastically reduced, and the elastic member 41 positioned on the rear side is elastically reduced. By enlarging, the first base portion 37 is tilted around the rotation axis 38 for tracking in the axial direction in accordance with the inclination of the metal tube 1 in the axial direction. Thus, the entire holding member 5 is maintained while the arm members 9 and 10 are elastically pressed against the metal tube 1 via the guide rollers 6 and 7 and the auxiliary guide rollers 24 and 25, respectively. Can be tilted.
As a result, the transmitter 2 and the receiver 3 of the probes 17 and 18 attached to the mounting base portions 22 and 23 of the pair of arm members 9 and 10 are moved in the axial direction of the metal tube being piped. It is possible to cause the transmitter 2 and the receiver 3 to follow the direction in which the transmission and reception of the surface wave are appropriately performed in the circumferential direction of the metal tube 1 by being inclined in accordance with the direction along the direction.

  In addition, when the metal pipe 1 in the pipe making is inclined upward in the pipe forming direction due to the upper slit generated at the time of roll forming, the pair of arm members 9, 10 is pushed through guide rollers 6 and 7 and auxiliary guide rollers 24 and 25 located on the rear side of the pass line. On the other hand, the elastic member 41 for tracking in the axial direction positioned on the rear side of the pass line is elastically reduced, and the elastic member 41 positioned on the front side is expanded to rotate the entire holding member 5 for tracking in the axial direction. Since it is tilted around the shaft 38, the same effect as that in the case where the lower slit occurs is obtained.

On the other hand, the radial direction follow-up mechanism 35 functions when the metal pipe 1 during pipe movement moves in the vertical radial direction, that is, in the vertical direction.
Depending on the shape after roll forming, the metal tube in the pipe making may move up and down on the pass line, and may be misaligned in the vertical direction. For example, in the process of moving on a pass line so as to wave up and down, even if the axis of the metal tube is horizontal, a state in which it is decentered in the vertical direction from a normal position can be considered. When measuring the outer peripheral length of a metal tube having a shape like this, when the metal tube moves upward, the metal tube moves away from the transmitter and receiver, while when the metal tube moves downward, the measuring device There is a possibility that the roundness may be changed by pressing the metal tube itself.
Then, even in this case, the transmission position and direction of the surface wave with respect to the outer surface of the metal tube by the transmitter, the reception position and direction of the surface wave by the receiver are deviated from an appropriate position and direction, and It becomes impossible to measure the exact outer circumference of the metal tube.
Therefore, in this embodiment and third and fourth embodiments described later, the holding member is moved in synchronization with the vertical movement of the metal tube during pipe making by the radial follow-up mechanism. Thus, the probe, that is, the transmitter and the receiver are made to follow the vertical misalignment of the metal pipe during pipe making.

Specifically, the radial follow-up mechanism 35 includes a second base 40 that is a part of the axial follow-up mechanism 36, and a support base 42 that is positioned below the second base 40. , And a radial follow-up elastic member 43 provided in a space between the lower surface of the second base portion 40 and the upper surface of the support base portion 42.
The support table 42 is fixedly placed on a stable floor surface or the like, and is formed in a flat plate shape.
The elastic member 43 for following in the radial direction elastically biases the second base portion 40 in the radial direction of the metal tube (in this case, vertically upward), and a spring or the like is used.
As a result, the radial follow-up mechanism 35 elastically biases the second base portion 40 in the radial direction of the metal tube, thereby allowing the entire holding member 5 to be moved via the first base portion 37. The metal tube 1 is always pressed in the radial direction.

FIG. 10 shows a state where the radial follow-up mechanism 35 functions and the holding member 5 follows the metal tube 1 moved in the vertical radial direction. A broken line shows a state before the radial follow-up mechanism 35 functions.
For example, when the metal pipe in the pipe making is displaced vertically in the vertical direction, the elastic means 43 for following in the radial direction is expanded, and the entire holding member 5 is made of the metal pipe via the second base portion 40. The state is raised in synchronization with the misalignment, and the state in which the pair of arm members 9 and 10 are pressed in the radial direction of the metal tube 1 is always maintained.
As a result, the transmitter 2 and the receiver 3 of the probes 17 and 18 can be made to follow the vertical misalignment of the metal tube 1 during pipe making, and the transmitter 2 and the receiver 3 are made of metal. An appropriate radial position can always be ensured without being separated from the outer peripheral surface of the tube 1.
When the metal pipe 1 in the pipe making is displaced vertically downward, the holding member 5 is pushed down in synchronization with the metal pipe 1 and the elastic means for following the radial direction is used. 43 shrinks. Thereby, since the state where the pair of arm members 9 and 10 are pressed in the radial direction of the metal tube 1 can be always maintained, it is possible to obtain the same effect as when the center is shifted vertically upward. Become.

The circumference measuring apparatus having the above configuration is basically used in the same manner as in the first embodiment to measure the circumference of the metal pipe 1 (including the open pipe) during pipe making.
At this time, since the circumference measuring apparatus of the second embodiment further includes a radial follow-up mechanism 35 and an axial follow-up mechanism 36 in addition to the circumferential follow-up mechanism 8, a metal tube in pipe making This corresponds to various behaviors of the metal tube 1 such as one horizontal misalignment, one vertical misalignment, and an axial tilt.
Thereby, the position of the transmitter 2 and the receiver 3 with respect to the metal tube 1 can be always set to appropriate positions, and the outer peripheral length of the metal tube 1 during pipe making can be measured more accurately.

FIGS. 11 to 13 show a third embodiment of the metal pipe circumference measuring apparatus of the present invention. The circumference measuring apparatus of this embodiment is the same as that of the second embodiment described above. Further, the holder includes a circumferential follow-up mechanism, a radial follow-up mechanism, and an axial follow-up mechanism, but the overall configuration is different from that of the second embodiment.
Note that the transmitter and receiver attached to the holder have the same configuration and operational effects as those of the first and second embodiments, and thus the same reference numerals are given and detailed description thereof is omitted.

That is, in the circumference measuring apparatus according to the third embodiment, the holder 4C includes the holding member 50 to which the transmitter and the receiver are attached, and the outer peripheral surface of the metal tube 1 of the transmitter 2 and the receiver 3. Guide rollers 51 and 52 for maintaining a constant distance from each other. Further, a circumferential follow-up mechanism 53, a radial follow-up mechanism 54, and an axial follow-up mechanism 55 are provided.
The holding member 50 includes a pair of arm members 56 and 57 that are bifurcated toward the upper side, a base portion 58 that is provided below the pair of arm members 56 and 57, and the pair of arms. A connecting portion 59 that connects the members 56 and 57 and the base portion 58 is provided.
In addition, about the rotating shaft which comprises the said connection part 59, and the said pair of bearing part, since it is the fundamentally the same structure and effect as the connection part of 1st and 2nd embodiment, The same reference numerals are given and detailed description is omitted.

Further, the pair of arm members 56 and 57 of the holding member 50 are all formed in a substantially L shape in a front view and a substantially U shape in a plan view as a whole.
Specifically, each of the arm members 56, 57 includes a pair of support portions 60, 60, 61, 61 formed in a prismatic shape extending in parallel to each other in a direction orthogonal to the pass line direction of the metal tube 1, and these Arm main body portions 62 and 63 are provided on the distal end sides of the pair of support portions 60, 60, 61, 61 so as to bridge the support portions 60, 60, 61, 61, respectively.
The arm main body portions 62, 63 are axially following bearing portions 64, 65 that are erected on the tip side, which is the upper side, and axially following the shaft portions rotatably supported by the bearing portions 64, 65. Rotary shafts 66 and 67, and tilting base portions 68 and 69 attached to the arm main body portions 62 and 63 via the rotary shafts 66 and 67 and the bearing portions 64 and 65, respectively. Further, between the support portions 60, 60 of the one arm member 56 and the support portions 61, 61 of the other arm member 57, plate-shaped interposition members 19, 19 used for opening degree adjustment and fixing thereof. Are arranged respectively.
Further, between the tilting table parts 68 and 69 and the pair of support parts 60 and 61, an axial follow-up elasticity that elastically biases the tilting table parts 68 and 69 in the radial direction of the metal tube. Members 71 and 72 are provided, respectively.

The pair of arm members 56 and 57 has a fixed opening degree between the pair of arm members 56 and 57 and the opening degree between the arm members 56 and 57 during the pipe making of the metal pipe 1. About the point which becomes adjustable, it is the same as the said 1st and 2nd embodiment.
The interposition member 19 has basically the same configuration as that of the first and second embodiments, and has the same reference numerals as those of the first and second embodiments in order to achieve the same effects. Detailed description will be omitted.
Further, regarding the opening adjustment between the arm members 56, 57, a plurality of holes provided at predetermined positions of the support portions 60, 60, 61, 61 of the arm members 56, 57 and the protruding portions of the interposition member 19 are provided. It is the same as that of the said 1st and 2nd embodiment about the point performed using the several hole provided in the predetermined position of 19b, 19b, and the pin inserted so that these holes may be penetrated.

Rotating shafts 66 and 67 for following the axial direction are arm members 56 and 57, more specifically, an extension line extending in the radial direction of the metal tube from the end of each arm main body 62 and 63, and the outer peripheral surface of the metal tube 1. Extends in a direction parallel to the tangent line that contacts, and is supported by the bearing portions 64 and 65 on the distal end side of the arm main body portions 62 and 63 so as to be rotatable about the axis thereof. ing.
The tilting table portions 68 and 69 are formed in a plate shape or a rectangular parallelepiped shape extending in the pass line direction, and have both functions of the transmitter 2 and the receiver 3 on the upper end side in the central portion in the longitudinal direction. The probes 73 and 74 are provided so as to protrude in the radial direction of the metal tube. Furthermore, the one end side of the rotating shafts 66 and 67 for tracking in the axial direction is fixed to the side surface on the outer side in the central portion in the longitudinal direction.
Therefore, these tilting base portions 68 and 69 are provided on the arm main body portions 62 and 63, more specifically, on the inner side of the tip ends of the axial follow-up bearing portions 64 and 65, and the axial follow-up rotary shaft 66. , 67 can be rotated together with the rotary shafts 66, 67.
Further, the elastic members 71 and 72 for following in the axial direction are between the lower surface side in the vicinity of both ends in the longitudinal direction of the tilting table portions 68 and 69 and the upper surface side of the pair of support portions 60, 60, 61, 61. Each is provided and a spring or the like is used.

The guide rollers 51 and 52 are provided on the upper end sides in the vicinity of both ends in the longitudinal direction of the tilting table portions 68 and 69 so as to sandwich the probes 73 and 74, respectively. It is freely rotatable in the direction.
Each of these guide rollers 51 and 52 protrudes in the direction of the metal tube 1 relative to the probes 73 and 74, and always contacts the outer peripheral surface of the metal tube 1 during tube formation while rotating. A gap is formed between the probes 73 and 74 and the metal tube 1, and the distance of the probes 73 and 74 from the outer peripheral surface of the metal tube 1 is always kept constant.
In the gaps between the probes 73 and 74, that is, the transmitter 2 and the receiver 3, and the outer peripheral surface of the metal tube 1 formed by the guide rollers 51 and 52, the first and second embodiments are provided. As in the embodiment, a medium such as water is always supplied.

The axial direction tracking mechanism 55 includes the arm main body portions 62 and 63, the rotation shafts 66 and 67 for axial direction tracking provided on the distal ends of the arm main body portions 62 and 63, and the tilting table portion 68. , 69 and the elastic members 71, 72 for tracking in the axial direction provided between the tilting table portions 68, 69 and the arm main body portions 62, 63.
Therefore, the axial direction follow-up mechanism 55 is capable of tilting the tilting table portions 68 and 69 about the rotation shafts 66 and 67 about the rotation shafts 66 and 67. On the other hand, the elastic members 71 and 72 elastically urge the tilt bases 68 and 69 in the radial direction of the metal tube, thereby the tilt bases of the holding member 50, particularly the pair of arm members 56 and 57. 68 and 69 are configured to always press against the outer peripheral surface of the metal tube 1 such that the longitudinal directions of the tilting table portions 68 and 69 are along the axial direction of the metal tube 1.

FIG. 14 shows a state where the axial direction follow-up mechanism 55 functions and the holding member 5, more specifically, the tilting base portions 68 and 69 that are a part of the holding member 5 are tilted.
When the metal pipe 1 in the pipe making is inclined downward in the pipe making direction due to, for example, the lower crevice generated at the time of roll forming, the tilt base parts 68 and 69 are The metal tube 1 is pressed through guide rollers 51 and 52 positioned on the front side of the pass line disposed on the tilting bases 68 and 69, respectively.
On the other hand, in accordance with the movement of each tilting base 68, 69, the elastic members 71, 72 for tracking in the axial direction positioned on the front side of the pass line are elastically reduced, and the elastic members 71 positioned on the rear side. , 72 expands elastically.
As a result, each of the tilting table portions 68 and 69 is elastically pressed against the metal tube 1 via the two guide rollers 51, 51, 52 and 52, respectively, in the axial direction of the metal tube 1. In such a manner, the actuators tilt about the axes of the rotary shafts 66 and 67 for tracking in the axial direction.
As a result, the transmitter 2 and receiver 3 of the probes 73 and 74 attached to the tilt bases 68 and 69 are tilted in accordance with the direction along the axial direction of the metal tube 1 during pipe making. The transmitter 2 and the receiver 3 can be made to follow the directions in which the transmission and reception of the surface waves are appropriately performed in the circumferential direction of the metal tube.

In addition, when the metal pipe 1 in the pipe making is tilted upward in the pipe forming direction due to the upper slit generated at the time of roll forming, each tilting base 68, 69 are pushed through the guide rollers 51 and 52 located on the rear side of the pass line.
On the other hand, the elastic members 71 and 72 for tracking in the axial direction located on the rear side of the pass line are elastically reduced, and the elastic members 71 and 72 located on the front side are elastically expanded. And each tilting stand part 68 and 69 is elastically pressed against the metal pipe 1 via the two guide rollers 51, 51, 52 and 52, respectively.
Thereby, since it inclines around the axis | shafts of the rotating shafts 66 and 67 for an axial direction follow along the axial direction of the metal pipe 1, the same effect as the case of a lower slit will be acquired.

The radial follow-up mechanism 54 includes a base 58 that is a part of the holding member 50, a support base 75 that is positioned below the base 58, and a lower surface and support of the base 58. And a radial follow-up elastic member 76 provided in a space between the upper surface of the base portion 75.
The support base 75 is fixedly placed on a stable floor surface or the like, and is formed in a flat plate shape.
The elastic member 76 for following in the radial direction elastically biases the base portion 58 in the radial direction of the metal tube (in this case, vertically upward), and a spring or the like is used.
Therefore, the radial follow-up mechanism 54 has the base portion 58 elastic in the radial direction of the metal tube by the radial follow-up elastic member 76 disposed between the base portion 58 and the support base portion 75. Thus, the entire holding member 50 is constantly pressed in the radial direction of the metal tube 1.
Thereby, the holding member 50 can be made to follow the metal pipe 1 in synchronization with the vertical movement of the metal pipe 1 during pipe making.
The configuration of the radial follow-up mechanism 54 of the third embodiment is that the second base 40 in the radial follow-up mechanism of the second embodiment is replaced with a base 58. Except for the above, the configuration is basically the same as that of the radial follow-up mechanism 35 of the second embodiment, and the same effect is obtained, and thus detailed description thereof is omitted.

Further, the circumferential follow-up mechanism 53 includes a connecting portion 59 (that is, the pair of bearing portions 28 and the rotating shaft 29) constituting a part of the holding member 50, and the arm members 56 and 57 having a diameter of a metal tube. And elastic members 77 and 78 for circumferential follow-up that are elastically biased in the direction. The elastic members 77 and 78 for following in the circumferential direction are provided in spaces between the base portion 58 and the base portions 19c and 19c of the interposition members 19 and 19, respectively. For example, springs or the like are used as the elastic members 77 and 78 for following in the circumferential direction.
The circumferential follow-up mechanism 53 is configured to cause the pair of arm members 56 and 57 to move the pair of arm members 56 and 57 around the rotating shaft 29 of the connecting portion 59 in accordance with the horizontal misalignment of the metal tube 1 during pipe making. Tilt to the left and right of the pass line. Then, the arm members 56 and 57 are always elastically pressed against the metal tube 1 in the radial direction of the metal tube by the elastic members 77 and 78 for following the circumferential direction.
Thereby, the holding member 50 can be tilted along the circumferential direction of the metal tube 1, and the probes 73 and 74 can be made to follow the horizontal misalignment of the metal tube 1 during pipe making.
Note that the circumferential follow-up mechanism has basically the same configuration and the same function and effect as the circumferential follow-up mechanism 8 of the first and second embodiments, and a detailed description thereof will be omitted.

The peripheral side hand apparatus according to the third embodiment having the above-described configuration is basically used in the same manner as in the first and second embodiments, and a metal pipe (including an open pipe) during pipe making. Measure the outer perimeter of the.
At this time, since the circumferential length measuring apparatus of the third embodiment includes the circumferential follow-up mechanism 53, the radial follow-up mechanism 54, and the axial follow-up mechanism 55, the horizontal direction of the metal pipe during pipe making This corresponds to various metal tube behaviors such as vertical misalignment, vertical misalignment, and axial tilt. Thereby, the position of the transmitter and the receiver with respect to the metal tube can be always set to an appropriate position, and the outer peripheral length of the metal tube during pipe making is more accurately measured as in the second embodiment. It becomes possible.

By the way, in the said 1st-3rd embodiment, a pair of arm member of a holding member can be installed so that the butt | matching part of a metal tube may be straddled, Thereby, the outer periphery length measurement of a metal tube is carried out. In this case, the surface wave transmitted from the probe transmitter can be prevented from passing through the abutting portion.
In this case, since various influences when the surface wave passes through the welded butt portion can be eliminated, there is an advantage that measurement accuracy is improved. Also, when measuring the outer peripheral length of a metal pipe in an open pipe state before welding the butt part, the surface wave is transmitted from the transmitter of one probe without considering the reflection of the surface wave at the butt part. Since it is only necessary to transmit and receive by the receiver of the other probe, measurement becomes easy. However, these benefits are not essential.

In the first to third embodiments, a probe having a transmitter and a receiver is provided on each of the pair of arm members constituting the holder holding member, and the transmitter and At least the transmitter of the receiver is attached, and at least the receiver is attached to the other arm.
However, in the fourth embodiment described below, in the configuration in which both the transmitter and the receiver are attached to only one arm member of the pair of arm members constituting the holding member of the holder, The holder includes a circumferential direction tracking mechanism, a radial direction tracking mechanism, and an axial direction tracking mechanism.

15 and 16 show a fourth embodiment of the metal pipe circumference measuring apparatus of the present invention. The circumference measuring apparatus of this embodiment constitutes the holding member 5 of the holder 4D. A configuration in which only one arm member 9 of the pair of arm members 9 and 10 includes a probe member 80 having two probes 81 and 82 having the functions of the transmitter 2 and the receiver 3. It has become. Therefore, unlike the second embodiment, the other arm member 10 is not provided with a configuration related to the probe.
The two probes 81 and 82 of the probe member 80 are the same as the probes 17, 18, 73 and 74 of the first to third embodiments, and are the transmitter 2 and the receiver 3. It has both functions, and basically has the same configuration and performance as the probes 17, 18, 73, and 74.
Further, the configuration other than that the probe member 80 having the probes 81 and 82 is provided only on one arm member 9 and the configuration related to the probe is not provided on the other arm member is substantially the same. In order to achieve the same effects as the second embodiment, the same reference numerals are given to the drawings, and detailed description is omitted.

Here, the probe member 80 is composed of the two probes 81 and 82 for the following reason.
That is, as shown in FIG. 5, when the transmitter and the receiver are arranged as separate probes, the entire length of the circumference of the metal tube is not measured by the surface wave, but the surface wave By adding the distance between the probes measured in advance as a known value to the distance measured in step 1, the total circumference of the metal tube was obtained. However, there is a possibility that an error may occur in the distance between the probes depending on the measurement conditions.
Therefore, in the circumference measuring apparatus according to the fourth embodiment, the probe member is composed of two probes, and the distance between each probe as the transmitter and the receiver is substantially zero. By doing so, it is possible to measure the entire circumference of the metal tube with surface waves.
As a result, the surface wave transmitted from the probe serving as the transmitter passes through the portion of the metal tube adjacent to the probe serving as the receiver. Long measurement accuracy will be greatly improved.

The other reason why the probe member 80 is composed of the two probes 81 and 82 is as follows.
That is, when the transmitter transmits a surface wave, it is necessary to emit from the transmitter at an emission angle where the angle between the propagation direction and the emission direction to the metal tube is an obtuse angle with respect to the surface of the metal tube. On the other hand, when the receiver receives a surface wave, it needs to be incident on the receiver at an incident angle where the angle between the propagation direction and the incident direction to the metal tube is an obtuse angle with respect to the surface of the metal tube. . However, when surface waves are propagated in the circumferential direction on the outer peripheral surface of a metal tube, even if the probe has both functions of a transmitter and a receiver, one probe emits an appropriate angle. It is impossible to ensure both the angle and the incident angle.
Therefore, in this embodiment, when the probe member 80 is composed of the two probes 81 and 82 and one probe functions as the transmitter 2, the other probe receives the probe. By making it function as the child 3, an appropriate emission angle of the surface wave is secured for the probe that becomes the transmitter 2, and an appropriate incident angle of the surface wave is secured for the probe that becomes the receiver 3, respectively. Appropriate surface wave can be transmitted and received.

The metal pipe circumference measuring apparatus having the above-described configuration can measure the outer circumference of the metal pipe after welding the butt portion. When measuring the outer circumference of the metal pipe during pipe making, This circumference measuring device is arranged at a position after welding of the butt portion on the pipe pass line.
Then, the opening between the pair of arm members 9 and 10 of the holding member 5 is adjusted according to the outer diameter of the metal tube 1 to be measured, and the transmitter 2 of the probe 17 and the metal tube 1 of the receiver 3. A metal pipe is formed on the outer peripheral surface of the metal pipe by setting the circumferential position to an appropriate position. At this time, the other arm member 10 not provided with the probe keeps the entire holder 4D in an appropriate posture by always bringing the guide roller 7 and the auxiliary guide roller 26 into contact with the outer peripheral surface of the metal tube.

FIG. 17 shows a case where the outer peripheral length of the metal tube 1 welded to the butt portion 1a is measured. In FIG. 17, the broken arrow indicates the propagation direction of the surface wave.
In this case, one of the two probes 81 and 82 of the probe member 80 provided on one arm member 9 is positioned on the left side of the probe member 80 in FIG. In this case, the surface wave transmitted from the transmitter 2 passes through the welded butted portion 1a, and the other probe 82 of the probe member 80 (FIG. 17). The probe is located on the right side of the probe member 80. In this case, the probe functions as the receiver 3.
Thus, the propagation time is measured, and the propagation distance of the surface wave, that is, the outer peripheral length of the metal tube 1 can be calculated from the propagation time and the known surface wave velocity.
In the case shown in FIG. 17, one probe 81 of the probe member 80 functions as the transmitter 2 and the other probe 82 functions as the receiver 3, respectively. Of course, the probe 81 may function as a receiver. In this case, the propagation direction of the surface wave is opposite to that in FIG.

According to the circumference measuring apparatus of the fourth embodiment having the above configuration, basically the same effect as that of the second embodiment can be obtained.
However, the probe 17 having the transmitter 2 and the receiver 3 is disposed only on one arm member 9 of the pair of arm members 9 and 10 constituting the holding member 5 of the holder 4D. Therefore, there are advantages that the number of parts is small compared to the second embodiment, and the entire configuration can be simplified.
In the case of the fourth embodiment, it is inevitable that the surface wave passes through the butted portion 1 a welded to the metal tube 1. However, the fourth embodiment is advantageous when the welding state is expected to be good or when the influence of the butt portion on the surface wave can be easily removed.

  In the said 1st-4th embodiment, the holder 4A-4D which hold | maintains the said transmitter 2 and the receiver 3 along the circumferential direction of the outer peripheral surface of the metal tube 1 of the metal tube 1 which makes a pipe Although it is arranged below the pass line, this holder may be arranged above the pass line of the metal tube.

In measuring the outer peripheral length of the metal pipe during pipe making, in order to cope with various behaviors of the metal pipe, in the holder 4A according to the first embodiment, only the circumferential follow-up mechanism is provided. In the holders 4B to 4D of the embodiment, in addition to the circumferential tracking mechanism, a radial tracking mechanism and an axial tracking mechanism are provided.
However, if the holder includes at least a circumferential tracking mechanism, the holder does not necessarily include a radial tracking mechanism or an axial tracking mechanism, and in addition to the circumferential tracking mechanism, Any one of the axial direction following mechanisms may be provided.

In the first to third embodiments, a probe having two functions of a transmitter for transmitting a surface wave toward the outer surface of the metal tube and a receiver for receiving the surface wave is provided. It is configured to be attached to a pair of arm members in the holding member of the holder.
However, it is sufficient that at least one of the transmitter and the receiver is attached to one arm member, and at least the receiver is attached to the other arm member. Can be selected as appropriate.

  In the first to fourth embodiments, the elastic member of the circumferential follow-up mechanism is replaced with the base (the first base in the second and fourth embodiments) and the interposition member. The elastic members of these circumferential tracking mechanisms can be elastically urged in the radial direction of the metal tube while the opening degree of each arm member is constant. Any position may be used.

DESCRIPTION OF SYMBOLS 1 Metal pipe 2 Transmitter 3 Receiver 4A-4D Holder 5,50 Holding member 6,7,51,52 Guide roller 8,53 Circumferential direction follower mechanism 9,10,56,57 Arm member 11,58 Base part 12 , 59 Connecting part 13, 14, 60, 61 Arm member support part 15, 16, 62, 63 Arm body part 17, 18, 73, 74, 81, 82 Probe (surface wave transmission / reception is possible)
DESCRIPTION OF SYMBOLS 19 Interposition member 19a Interposition member main body part 19b Interposition member protrusion part 19c Interposition member base part 19d Interposition member connection member 20, 21 Arm body part concave part 22, 23 Mounting base part 24, 25 Auxiliary guide roller 26, 27 Elasticity Member 28 Bearing part (holding member, circumferential follow-up mechanism)
29 Rotating shaft (holding member, circumferential tracking mechanism)
30, 31, 77, 78 Elastic member 35 for circumferential follow-up 35, 54 Radial follow-up mechanism 36, 55 Axis follow-up mechanism 37 First base 38, 66, 67 Rotating shaft 39 for axial follow-up 39, 64 , 65 Bearing (Axial tracking mechanism)
40 Second base portion 41, 71, 72 Elastic member for tracking in axial direction 42, 75 Supporting base portion 43, 76 Elastic member for following in radial direction 68, 69 Tilt base portion 80 Probe member

Claims (8)

While rewinding the coil of the metal plate, the metal plate is formed into a cylindrical shape with a plurality of rolls, and the outer peripheral length of the metal tube formed by abutting both ends in the width direction of the metal plate is A circumference measuring device that measures using surface waves propagated in the circumferential direction of
Arranged on the upper side or the lower side of the metal tube, a transmitter for transmitting the surface wave from the transmitter to the outer circumferential surface of the metal tube being piped in the circumferential direction, a receiver for receiving the surface wave from the transmitter A holder for holding these transmitter and receiver along the circumferential direction of the outer peripheral surface of the metal tube,
The holder includes a holding member to which the transmitter and the receiver are attached, a guide roller for maintaining a constant distance from the outer peripheral surface of the metal tube of the transmitter and the receiver, and the transmitter and the receiver are being piped. A circumferential follow-up mechanism that follows the horizontal misalignment of the metal tube,
The holding member has a pair of arm members that are bifurcated. At least one of the transmitter and the receiver is attached to one arm member, and at least the receiver is attached to the other arm member. Being
The guide rollers are respectively arranged on the distal end sides of the arm members of the holding member, and are rotatable in the pass line direction of the metal tube in a state where the guide roller is always in contact with the outer peripheral surface of the metal tube during pipe making,
The circumferential tracking mechanism, Ri configuration der tilting along the holding member in the circumferential direction of the metal pipe in pipe-making,
The holding member is capable of adjusting the opening between the pair of arm members, and can change the interval between the transmitter and the receiver according to the outer diameter of the metal tube. An apparatus for measuring the circumference of a metal tube, wherein the opening degree can be fixed during circumference measurement. While rewinding the coil of the metal plate, the metal plate is formed into a cylindrical shape with a plurality of rolls, and the outer peripheral length of the metal tube formed by abutting both ends in the width direction of the metal plate is A circumference measuring device that measures using surface waves propagated in the circumferential direction of
Arranged on the upper side or the lower side of the metal tube, a transmitter for transmitting the surface wave from the transmitter to the outer circumferential surface of the metal tube being piped in the circumferential direction, a receiver for receiving the surface wave from the transmitter A holder for holding these transmitter and receiver along the circumferential direction of the outer peripheral surface of the metal tube,
The holder includes a holding member to which the transmitter and the receiver are attached, a guide roller for maintaining a constant distance from the outer peripheral surface of the metal tube of the transmitter and the receiver, and the transmitter and the receiver are being piped. A circumferential follow-up mechanism that follows the horizontal misalignment of the metal tube,
The holding member has a pair of arm members branched in a bifurcated shape, and the transmitter and the receiver are attached only to one arm member,
The guide rollers are respectively arranged on the distal end sides of the arm members of the holding member, and are rotatable in the pass line direction of the metal tube in a state where the guide roller is always in contact with the outer peripheral surface of the metal tube during pipe making,
The circumferential tracking mechanism, Ri configuration der tilting along the holding member in the circumferential direction of the metal pipe in pipe-making,
The holding member is capable of adjusting the opening between the pair of arm members, and can change the interval between the transmitter and the receiver according to the outer diameter of the metal tube. An apparatus for measuring the circumference of a metal tube, wherein the opening degree can be fixed during circumference measurement.   The circumferential follow-up mechanism includes a rotating shaft provided on the proximal end side of the pair of arm members of the holding member and extending in the pass line direction of the metal tube, and each arm member is elastically attached to the radial direction of the metal tube. 3. The structure according to claim 1, further comprising an elastic member for biasing, wherein the pair of arm members are tilted along the circumferential direction of the metal tube in the pipe making centering on the rotating shaft. An apparatus for measuring the circumference of a metal tube as described in 1. The holder moves the holding member in synchronism with the vertical movement of the metal pipe during pipe making, and the transmitter and receiver follow the vertical misalignment of the metal pipe during pipe making. The peripheral measurement apparatus for a metal pipe according to any one of claims 1 to 3 , further comprising a radial direction following mechanism. 5. The circumference measuring apparatus for a metal pipe according to claim 4 , wherein the radial follow-up mechanism has an elastic member that elastically biases the entire holding member in the radial direction of the metal pipe. When the metal pipe in the pipe making is inclined in the vertical direction, the holder tilts the holding member along the vertical inclination of the metal pipe so that the transmitter and the receiver are piped. An axial direction tracking mechanism is provided that is inclined in a direction along the axial direction of the inner metal tube and that follows the direction in which the transmission and reception of surface waves are performed in the circumferential direction of the metal tube. The circumference measurement apparatus of the metal pipe in any one of Claim 5 . The axial direction following mechanism includes a first base portion to which the base end sides of the pair of arm members are coupled, and a horizontal direction that is provided on the first base portion and orthogonal to the pass line direction of the metal tube. A second base portion including a rotation shaft extending, a bearing portion rotatably supported around the rotation shaft about the rotation shaft, and a first base portion and a second base portion And an elastic member that elastically biases the first base portion in the radial direction of the metal tube, and tilts the first base portion about the rotation axis. The metal tube circumference measuring apparatus according to claim 6 , wherein the entire holding member is tilted in a direction along the axial direction of the metal tube. The axial direction follow-up mechanism has a contact at a point where an extension line extending in the radial direction of the metal tube from the tip of each arm member and the outer peripheral surface of the metal tube are provided on each tip side of the pair of arm members. A rotating shaft extending in parallel with the tangent line, and a tilting table that is connected to each arm member via the rotating shaft and at least one of a transmitter and a receiver is attached and is rotatable about the axis of the rotating shaft And an elastic member that is provided between the tilting base part and the arm member and elastically biases the tilting base part in the radial direction of the metal tube, with the rotation axis as a center. The circumference measuring apparatus for a metal tube according to claim 6 , wherein the transmitter and the receiver are inclined in a direction along the axial direction of the metal tube in the tube by tilting the tilting table portion. .

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