JP2017032354A - Device for measuring wall thickness and displacement of inner and outer surfaces of tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for measuring a wall thickness and displacement of inner and outer surfaces of a tube, which can efficiently measure a wall thickness and displacement of inner and outer surfaces of a tube, and eventually can evaluate undulation of the inner and outer surfaces of the tube.SOLUTION: A measurement device 100 related to the present invention comprises: a U-shaped member 1 including a first arm part 11 and a second arm part 12; a first contact piece 2 attached to the first arm part on an open end side of the U-shaped member; a contact type displacement gauge 3 comprising a second contact piece 32 attached to the second arm part; energization means 4 energizing the U-shaped member so that the first contact piece contacts with the inner surface of a pipe P; a displacement gauge 5 configured to measure displacement of the U-shaped member; movement means 6 integrally relatively moving the U-shaped member and the like in an axial direction of the pipe; and calculation means 7 calculating a wall thickness of the pipe on the basis of a displacement measurement value of the contact type displacement gauge, calculating displacement of the inner surface of the pipe on the basis of a displacement measurement value of the displacement gauge, and calculating displacement of an outer surface of the pipe on the basis of the displacement measurement values of the contact type displacement gauge and displacement gauge.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an apparatus for measuring the thickness of a pipe such as a seamless pipe and the displacement of the inner and outer surfaces. In particular, the present invention can efficiently measure the wall thickness and inner / outer surface displacement of the tube, and thus can evaluate the inner / outer surface undulation represented by the axial distribution of the inner / outer surface displacement of the tube. The present invention relates to an outer surface displacement measuring apparatus.

As a method for manufacturing a seamless pipe, various methods such as a mandrel mill method, a plug mill method, a Eugene Sejurnee method, and an Erhard push bench method are known. Regardless of which method is used, the seamless pipe is manufactured through a plurality of processes, so that the thickness fluctuation generated in each process is added and remains in the product.
For this reason, efforts have been made to analyze the wall thickness distribution of products and identify the cause of wall thickness defects in each process (for example, see Patent Documents 1 and 2).
However, as described in Patent Documents 1 and 2, frequency analysis such as Fourier analysis used to analyze the wall thickness distribution requires a large amount of measurement data in the axial and circumferential directions of the tube.

As a method for measuring the wall thickness of a tube, a method using ultrasonic waves is widely used. This is because a contact medium such as water is interposed between the surface of the tube and the ultrasonic probe, ultrasonic waves are incident on the tube from the ultrasonic probe through the contact medium, and the echo of the tube is detected. This is a method for measuring thickness. By rotating the tube in the circumferential direction relative to the ultrasonic probe and moving it in the axial direction, the thickness distribution in the axial direction and the circumferential direction of the tube is measured.
However, in the above method, it is easy to include noise in measurement of a product from which the scale formed on the surface is not removed, and the measurement error increases. In addition, the wall thickness measuring device shall be directly connected to the pipe production line in order to quickly measure the wall thickness of the pipe after production and to quickly determine whether the measured value is within the allowable range. There are many. Therefore, even if a measurement error due to noise or the like is suspected and it is necessary to re-measure, re-measurement using a thickness measuring device directly connected to the production line as described above is There is a problem of adjustment and transportation for returning the pipe to the production line again, which is not easy.

  Therefore, in order to re-measure the wall thickness when there is doubt about the wall thickness measurement value, the wall thickness is measured point by point using a hand-held ultrasonic thickness gauge, or the wall thickness is measured using a micrometer. However, it is difficult to obtain a large amount of measurement data by these methods. For this reason, it is desired to develop an apparatus capable of saving the thickness measurement and shortening the measurement time.

  In addition, when efforts are made to increase the dimensional accuracy of a pipe using a small experimental mill, it is necessary to analyze the axial and circumferential thickness measurement data of the pipe manufactured by the small mill as well. .

  Furthermore, the seamless pipe may swell on the inner and outer surfaces (changes in the inner and outer surface displacements along the axial direction of the pipe), which may contribute to poor quality. For this reason, it is also necessary to measure the swell simultaneously with the thickness measurement.

Similar to a micrometer or the like, for example, devices described in Patent Documents 3 and 4 have been proposed as devices for measuring the wall thickness of a tube by a contact method.
However, although the apparatuses described in Patent Documents 3 and 4 can measure the wall thickness of the pipe, they are not configured to measure the undulation of the inner and outer surfaces of the pipe.

Japanese Patent No. 4232791 JP-A-61-135409 Japanese Utility Model Publication No. 5-76610 JP-A-8-219703

  The present invention has been made to solve the above-described problems of the prior art, and can efficiently measure the wall thickness and displacement of the inner and outer surfaces of the tube, and thereby evaluate the undulation of the inner and outer surfaces of the tube. It is an object of the present invention to provide a tube thickness and inner / outer surface displacement measuring device that can be used.

  In order to solve the above problems, the present invention includes a first arm part and a second arm part arranged in parallel to face the first arm part, and the first arm part and the second arm part are A U-shaped member connected at one end, a first contact attached to the first arm so as to face the second arm at the open end of the U-shaped member; At the open end side of the U-shaped member, it is attached to the second arm portion so as to face the first contactor, and is attached to the shaft member capable of moving forward and backward in the facing direction and the tip of the shaft member. A contact displacement meter that includes a second contact and measures the displacement of the second contact according to the amount of advancement and retraction of the shaft member; and the first arm is located inside the tube, and the second arm Is located outside the tube, and the first arm and the second arm When the U-shaped member is arranged so that the groove portion is substantially parallel to the axial direction of the tube, the first contact attached to the first arm portion is placed on the inner surface of the tube. An urging means for urging the U-shaped member in the opposing direction of the first arm portion and the second arm portion so as to contact each other, and a displacement in the urging direction of the U-shaped member are measured. A displacement meter; a U-shaped member; the first contact; the contact displacement meter; the biasing means; and a moving means for relatively moving the displacement meter integrally in the axial direction of the tube; and the contact The thickness of the tube is calculated based on the displacement measurement value by the displacement meter, the displacement of the inner surface of the tube is calculated based on the displacement measurement value by the displacement meter, the displacement measurement value by the contact displacement meter, and the displacement meter Computing means for calculating the displacement of the outer surface of the pipe based on the displacement measurement value by Providing the wall thickness and inner and outer surfaces displacement measuring apparatus of a tube according to claim Rukoto.

According to the measuring apparatus of the present invention, the U-shaped member or the like is relatively moved in the axial direction of the tube by the moving means, the first arm portion is located inside the tube, and the second arm portion is located outside the tube. The circumferential direction of the pipe is located from the open end of the U-shaped member to the inside of the U-shaped member so that the first arm part and the second arm part are substantially parallel to the axial direction of the pipe. The U-shaped member is urged by the urging means in the opposing direction of the first arm part and the second arm part, and the first contact attached to the first arm part is It will contact the inner surface of the tube. Then, the displacement of the U-shaped member in the biasing direction (opposite direction of the first arm portion and the second arm portion) is measured by the displacement meter. Since the displacement measurement value by this displacement meter changes only in accordance with the displacement of the inner surface of the tube with which the first contactor comes into contact, the calculation means easily calculates the displacement of the inner surface of the tube based on the displacement measurement value by the displacement meter. Is possible.
Further, in the above state, by moving the shaft member included in the contact displacement meter forward and backward to bring the second contactor into contact with the outer surface of the pipe, the displacement of the second contactor according to the amount of forward and backward movement of the shaft member is achieved. Measured. For example, if only the position of the inner surface of the tube changes along the axial direction of the tube and the thickness of the tube is constant, the position of the outer surface of the tube with which the second contactor contacts is the amount of change in the position of the inner surface. Will change by the same amount. However, since the contact displacement meter is attached to the U-shaped member, the position of the inner surface of the tube changes, and the U-shaped member is urged and moved by the urging means. The position of the displacement meter (the position of the shaft member and the second contact) also changes by the same amount as the amount of movement of the U-shaped member (that is, the amount of change in the position of the inner surface of the tube). For this reason, even if the position of the outer surface of the tube with which the second contactor contacts is changed, the shaft member of the contact displacement meter does not move back and forth, so that the displacement measurement value by the contact displacement meter does not change. In other words, since the displacement measurement value by the contact displacement meter changes only according to the thickness of the tube, the computing means can easily calculate the tube thickness based on the displacement measurement value by the contact displacement meter. is there.
Furthermore, since the displacement of the outer surface of the tube can be calculated by adding the thickness of the tube to the displacement of the inner surface of the tube, the computing means can calculate the displacement based on the displacement measurement value by the contact displacement meter and the displacement measurement value by the displacement meter. The displacement of the outer surface can be easily calculated.
Then, while the U-shaped member or the like is relatively moved in the axial direction of the pipe by the moving means, the calculating means evaluates the axial thickness distribution of the pipe thickness by calculating the thickness of the pipe, and the calculating means calculates the pipe thickness. By calculating the displacement of the inner and outer surfaces, it is possible to evaluate the undulation of the inner and outer surfaces of the pipe.
Furthermore, if the tube is rotated relative to the measuring device according to the present invention in the circumferential direction, measurement over the entire circumference of the tube is also possible.

As described above, according to the present invention, it is possible to easily measure the wall thickness of the tube as compared with the case where the wall thickness is measured using a handy type ultrasonic thickness meter or a micrometer. In addition, the displacement of the inner and outer surfaces of the tube can be measured simultaneously with the thickness of the tube, so that the undulation of the inner and outer surfaces of the tube can be evaluated.
Further, according to the present invention, the displacement of the U-shaped member is not measured directly at the portion of the inner surface of the tube that is in contact with the first contact, but by the displacement meter that can be disposed outside the tube, As a result, the displacement of the inner surface of the tube is measured. That is, the first contact does not constitute a part of a contact displacement meter attached to a shaft member that can move forward and backward like the second contact. For this reason, compared with the case where contact displacement meters are arranged inside and outside the tube and the thickness of the tube is measured, the size of the member inserted into the tube can be reduced. Can measure wall thickness and inner / outer surface displacement.

As the “displacement meter” for measuring the displacement in the urging direction of the U-shaped member in the present invention, a contact displacement meter similar to the contact displacement meter including the second contact can be used. is there. However, since the U-shaped member is less affected by the scale and the like, unlike the tube, the “displacement meter” of the present invention is not necessarily limited to the contact displacement meter, and a non-contact displacement meter such as a laser displacement meter is used. It is also possible to use it.
In addition, as the “moving means” for relatively moving the U-shaped member or the like integrally in the axial direction of the pipe in the present invention, a uniaxial stage connected to the U-shaped member or the like can be exemplified. However, the “moving means” of the present invention is not necessarily limited to the one that moves the U-shaped member or the like, but a tube such as a conveyance roller that supports a horizontally arranged tube from below and can convey the tube in the axial direction. It is also possible to use means for moving one of them in the axial direction.

Specifically, the calculation means of the present invention can calculate the thickness of the tube, the displacement of the inner surface of the tube, and the displacement of the outer surface of the tube as follows.
That is, the calculation means sets the displacement measurement value by the contact displacement meter when calibrating with a calibration material having a thickness A between the first contact and the second contact as UO ₀ , a displacement value measured by the contact type displacement gauge in a state in which one contact is the contact and the second contact on the inner surface of the tube in contact with the outer surface of the tube and UO _n, the displacement value measured by the displacement meter When UI _n is set, the thickness of the tube, the displacement of the inner surface of the tube, and the displacement of the outer surface of the tube can be calculated by the following formulas (1) to (3).
Tube thickness = UO _n −UO ₀ + A (1)
Displacement of the inner surface of the tube = UI _n −B (2)
Displacement of the outer surface of the pipe = UI _n −B + UO _n −UO ₀ + A (3)
However, B in the above formulas (2) and (3) means an arbitrary constant. The displacement measurement value by the contact displacement meter is increased when the second contact is displaced in a direction away from the first contact.

  According to the present invention, the thickness of the tube and the displacement of the inner and outer surfaces can be measured efficiently, and consequently, the undulation of the inner and outer surfaces of the tube can be evaluated.

FIG. 1 is a diagram schematically showing a schematic configuration of a tube thickness and inner / outer surface displacement measuring apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a schematic configuration of a modified example of the pipe thickness and inner / outer surface displacement measuring apparatus according to the present invention. FIG. 3 is a diagram illustrating an example of a result of measuring a pipe end portion of a seamless pipe that has been cold-worked after pipe-making by the Eugene Sejurune method using the measurement apparatus illustrated in FIG. 1. FIG. 4 is a diagram showing another example of a result of measuring a pipe end portion of a seamless pipe that has been cold-worked after pipe-making by the Eugene Sejurune method using the measuring apparatus shown in FIG. FIG. 5 is a diagram showing an example of the result of measuring the wall thickness of a seamless pipe pierced and rolled by a Mannesmann Piercer experimental mill using the measuring apparatus shown in FIG.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings as appropriate.
FIG. 1 is a diagram schematically showing a schematic configuration of a tube thickness and inner / outer surface displacement measuring device (hereinafter simply referred to as “measuring device”) according to an embodiment of the present invention. FIG. 1A is a front view seen from a horizontal direction orthogonal to the axial direction of the pipe P, FIG. 1B is a plan view, and FIG. 1C is an AA in FIG. It is arrow sectional drawing. In FIG. 1A, the pipe P is shown in a sectional view. In FIG. 1B, the calculation means 7 is not shown.
As shown in FIG. 1, the measuring apparatus 100 according to the present embodiment includes a U-shaped member 1, a first contact 2, a contact displacement meter 3, an urging means 4, a displacement meter 5, The moving means 6 and the calculating means 7 are provided. Moreover, the measuring apparatus 100 which concerns on this embodiment is provided with the holding means 8 which hold | maintains the pipe | tube P as a preferable form.

  The U-shaped member 1 includes a first arm portion 11 and a second arm portion 12 disposed in parallel to face the first arm portion 11. In the example illustrated in FIG. 1A, the second arm portion 12 is disposed above and in parallel with the first arm portion 11. Further, the U-shaped member 1 of the present embodiment includes a connecting member 13 disposed on one end side of the first arm portion 11 and the second arm portion 12. One end sides of the first arm portion 11 and the second arm portion 12 are respectively coupled to the connecting member 13, whereby the one end sides of the first arm portion 11 and the second arm portion 12 are connected.

  The first contact 2 has a first arm portion so as to face the second arm portion 12 on the open end side of the U-shaped member 1 (the other end side of the first arm portion 11 and the second arm portion 12). 11 is attached. In the example shown in FIG. 1A, the first contact 2 is attached to the upper side of the first arm portion 11 on the other end side of the first arm portion 11.

  The contact displacement meter 3 is attached to the second arm portion so as to face the first contact 2 on the open end side of the U-shaped member 1. The contact-type displacement meter 3 includes a shaft member 31 capable of moving back and forth in the facing direction (the vertical direction in the example shown in FIG. 1A) and the tip of the shaft member 31 (the lower end in the example shown in FIG. 1A). The second contactor 32 attached to the head is measured, and the displacement of the second contactor 32 corresponding to the amount of forward / backward movement of the shaft member 31 is measured. As the contact displacement meter 3, various commercially available contact displacement meters can be selected and applied according to the displacement measurement range. The contact displacement meter 3 includes an urging member (not shown) configured by a spring or the like that urges the shaft member 31 in the direction in which the shaft member 31 is moved forward.

  The biasing means 4 has a first arm portion 11 (at least the other end side of the first arm portion 11) positioned inside the pipe P, and a second arm portion 12 (at least the other end side of the second arm portion 12). When the U-shaped member 1 is arranged so that the first arm portion 11 and the second arm portion 12 are positioned substantially outside the tube P and are substantially parallel to the axial direction of the tube P (FIG. 1). In the state shown in (a), the U-shaped member 1 is moved to the first arm portion 11 and the second arm so that the first contact 2 attached to the first arm portion 11 contacts the inner surface of the pipe P. The portion 12 is biased in the facing direction (upward in the example shown in FIG. 1A). Specifically, the biasing means 4 of this embodiment includes a shaft member 41 having one end coupled to the connecting member 13 and the other end coupled to the moving member 62, and an elastic member (spring) wound around the shaft member 41. 42). One end (the upper end in the example shown in FIG. 1A) of the spring 42 abuts on one end (the lower end in the example shown in FIG. 1A) of the connecting member 13, and the other end (shown in FIG. 1A). In the example, the lower end is in contact with the upper surface of the moving member 62 and is attached in a state shorter than the natural length. As a result, an upward biasing force F acts on the connecting member 13 and thus the U-shaped member 1.

  The displacement meter 5 measures the displacement of the U-shaped member 1 in the urging direction (vertical direction). The displacement meter 5 of the present embodiment is a contact displacement meter similar to the contact displacement meter 3, and includes a shaft member capable of moving forward and backward in the biasing direction, and a contact attached to the tip of the shaft member. The displacement of the contact according to the amount of advancement and retraction of the shaft member is measured. Specifically, the main body of the displacement meter 5 is attached to the connecting member 13, and the contact of the displacement meter 5 is disposed so as to contact the upper surface of the moving member 62, so that the connecting member 13 and thus the U-shaped member. A displacement of 1 is measured. The displacement meter 5 is not necessarily limited to the contact displacement meter, and a non-contact displacement meter such as a laser displacement meter can also be used.

  The moving means 6 moves the U-shaped member 1, the first contact 2, the contact displacement meter 3, the urging means 4 and the displacement meter 5 integrally relative to each other in the axial direction of the pipe P. Specifically, the moving means 6 of the present embodiment is a uniaxial stage including a base 61 and a moving member 62 that moves on the base 61 in the axial direction of the pipe P. Since the shaft member 41 of the urging means 4 is coupled to the moving member 62 as described above, the urging force provided with the shaft member 41 and the spring 41 when the moving member 62 moves in the axial direction of the pipe P. The means 4 also moves in the axial direction of the pipe P. Thereby, the U-shaped member 1 coupled to the shaft member 41, the first contact 2 attached to the U-shaped member 1, the contact-type displacement meter 3, the biasing means 4, and the displacement meter 5 are also integrated. Therefore, it moves in the axial direction of the pipe P. The moving means 6 is not necessarily limited to moving the U-shaped member or the like. The moving means 6 supports the horizontally arranged pipe P from below, and includes a conveyance roller that can carry the pipe P in the axial direction. It is also possible to use means for moving the direction in the axial direction.

The calculation means 7 calculates the thickness of the pipe P based on the displacement measurement value by the contact displacement meter 3, calculates the displacement of the inner surface of the tube P based on the displacement measurement value by the displacement meter 5, and The displacement of the outer surface of the pipe P is calculated based on the displacement measurement value and the displacement measurement value by the displacement meter 5.
Specifically, the calculation means 7 sets UO ₀ as a displacement measurement value by the contact displacement meter 3 when calibrating with a calibration material having a thickness A between the first contact 2 and the second contact 32. The displacement measured value by the contact displacement meter 3 in a state where the first contactor 2 is in contact with the inner surface of the tube P and the second contactor 32 is in contact with the outer surface of the tube P (the state shown in FIG. 1A). was a UO _n, when the displacement measured by the displacement gauge 5 was UI _n, the following equation (1) to (3), the wall thickness of the pipe P, the displacement of the outer surface of the displacement and the pipe P of the inner surface of the pipe P Is calculated.
Tube thickness = UO _n −UO ₀ + A (1)
Displacement of the inner surface of the tube = UI _n −B (2)
Displacement of the outer surface of the pipe = UI _n −B + UO _n −UO ₀ + A (3)
However, B in the above formulas (2) and (3) means an arbitrary constant. Further, the displacement measurement value by the contact displacement meter 3 is increased when the second contact 32 is displaced in a direction away from the first contact 2 (when the shaft member 31 is retracted).

The calculation means 7 is connected to, for example, the contact displacement meter 3 and the displacement meter 5, and is based on the displacement measurement values input from the contact displacement meter 3 and the displacement meter 5, respectively, according to the above formulas (1) to (3). It is comprised by PLC (programmable logic controller) programmed so that the operation represented may be performed.
Note that the computing means 7 of this embodiment also functions as a control means for driving the moving means 6. Specifically, the calculation means 7 is connected to a drive source (not shown) of a uniaxial stage that is the movement means 6 and commands to move the movement member 62 of the movement means 6 in the axial direction of the pipe P at a constant speed. It is programmed to output a signal to the drive source. Thereby, the thickness of the tube P and the displacement of the inner and outer surfaces of the tube P can be continuously measured in the axial direction of the tube P.

  The holding means 8 includes an abutting member 81 that abuts the outer surface of the pipe P to support and position the pipe P, and a support column 82 that is erected on the base 61 of the moving means 6 and to which the abutting member 81 is attached. I have. In this embodiment, four contact members 81 are provided on the top, bottom, left, and right, and each contact member 81 is attached to the support column 82 so that its position can be adjusted in the horizontal direction (left and right). By adjusting the position of each abutting member 81 according to the outer diameter of the pipe P to be measured, the pipe P is held at an appropriate position for measuring the thickness and the like. The holding means 8 is not necessarily limited to the form shown in FIG. 1, and various forms can be adopted as long as the pipe P can be held at an appropriate position for measuring the thickness and the like.

  According to the measuring apparatus 100 having the above-described configuration, the U-shaped member 1 or the like is relatively moved in the axial direction of the pipe P by the moving means 6, and the first arm portion 11 is located inside the pipe P. The U-shaped member 1 of the U-shaped member 1 is arranged such that the second arm portion 12 is located outside the tube P, and the first arm portion 11 and the second arm portion 12 are substantially parallel to the axial direction of the tube P. In a state where a part of the pipe P in the circumferential direction is inserted from the open end to the inside of the U-shaped member 1 (the state shown in FIG. 1A), the U-shaped member 1 is The first contact 2 attached to the first arm 11 that is biased in the opposing direction of the first arm 11 and the second arm 12 comes into contact with the inner surface of the pipe P. Then, the displacement meter 5 measures the displacement of the U-shaped member 1 in the urging direction (opposite direction of the first arm portion 11 and the second arm portion 12). Since the displacement measurement value by the displacement meter 5 changes only in accordance with the displacement of the inner surface of the pipe P with which the first contactor 2 comes into contact, the calculation means 7 is based on the displacement measurement value by the displacement meter 5 and the formula (2 ) Can easily calculate the displacement of the inner surface of the pipe P.

  Further, in the above-described state (the state shown in FIG. 1A), the shaft member 31 provided in the contact displacement meter 3 is advanced by an urging force by an urging member (not shown) or resists the urging force. Then, the displacement of the second contactor 32 according to the amount of advancement / retraction of the shaft member 31 is measured by retracting and bringing the second contactor 32 into contact with the outer surface of the pipe P. For example, if only the position of the inner surface of the tube P changes along the axial direction of the tube P and the thickness of the tube P is constant, the position of the outer surface of the tube P with which the second contactor 32 contacts is the inner surface. It will change by the same amount as the change amount of the position of. However, since the contact displacement meter 3 is attached to the U-shaped member 1, the U-shaped member 1 is urged and moved by the urging means 4 when the position of the inner surface of the pipe P changes. Accordingly, the position of the contact displacement meter 3 (the position of the shaft member 31 and the second contact 32) is also the same amount as the amount of movement of the U-shaped member 1 (that is, the amount of change in the position of the inner surface of the tube P). Will change. For this reason, even if the position of the outer surface of the pipe P with which the second contactor 32 contacts is changed, the shaft member 31 of the contact displacement meter 3 does not move forward and backward, so that the displacement measurement value by the contact displacement meter 3 does not change. It will be. In other words, since the displacement measurement value by the contact displacement meter 3 changes only in accordance with the thickness of the pipe P, the calculation means 7 is based on the displacement measurement value by the contact displacement meter 3 according to the equation (1). The thickness of the tube P can be easily calculated.

Furthermore, since the displacement of the outer surface of the tube P can be calculated by adding the thickness of the tube P to the displacement of the inner surface of the tube P, the computing means 7 can calculate the displacement measured by the contact displacement meter 3 and the displacement meter 5. Based on the displacement measurement value, the displacement of the outer surface of the pipe P can be easily calculated by the equation (3).
Then, while the U-shaped member 1 and the like are relatively moved in the axial direction of the pipe P by the moving means 6, the calculating means 7 calculates the thickness of the pipe P, thereby evaluating the axial distribution of the thickness of the pipe P. Then, the swell of the inner and outer surfaces of the pipe P can be evaluated by the calculation means 7 calculating the displacement of the inner and outer surfaces of the pipe P.
Furthermore, if the pipe P is relatively rotated in the circumferential direction with respect to the measuring apparatus 100 (manually or a rotating means for rotating the pipe P in the circumferential direction may be provided and rotated by this rotating means), the pipe P Measurement over the entire circumference is also possible.

As described above, according to the measuring apparatus 100 according to the present embodiment, it is possible to easily measure the thickness of the pipe P as compared with the case where the thickness is measured using a handy type ultrasonic thickness meter or a micrometer. It is. In addition, the displacement of the inner and outer surfaces of the tube P can be measured simultaneously with the thickness of the tube P, and consequently the undulation of the inner and outer surfaces of the tube P can be evaluated.
Moreover, according to the measuring apparatus 100 which concerns on this embodiment, the displacement meter 5 which can be arrange | positioned on the exterior of the pipe | tube P is not measured directly in the site | part of the inner surface of the pipe | tube P which the 1st contactor 2 contacts. As a result, the displacement of the U-shaped member 1 and the displacement of the inner surface of the tube P are measured. That is, the first contact 2 does not constitute a part of a contact-type displacement meter attached to a shaft member that can move forward and backward like the second contact 32. For this reason, compared with the case where the contact-type displacement meter is arrange | positioned inside and outside the pipe | tube P and the thickness of the pipe | tube P is measured, the member inserted in the pipe | tube P (in this embodiment, the 1st arm part 11) Since the dimensions of the first contact 2) can be reduced, the thickness and inner / outer surface displacement can be measured even with the pipe P having a small inner diameter.

FIG. 2 is a diagram schematically showing a schematic configuration of a modified example of the measuring apparatus according to the present invention. FIG. 2A is a front view showing a first modification, FIG. 2B is a front view showing a second modification, and FIG. 2C is a front view showing a third modification. FIG. In FIG. 2, the calculation means 7 is not shown.
As shown in FIG. 2A, the measuring device 100A according to the first modification differs from the measuring device 100 shown in FIG. 1A in that the biasing means 4 is located above the connecting member 13 (second arm portion). 12 side). For this reason, the spring 42 of the biasing means 4 is attached in a state longer than the natural length. As a result, an upward biasing force F acts on the connecting member 13 and thus the U-shaped member 1 so that the first contact 2 attached to the first arm portion 11 contacts the inner surface of the pipe P. Become. Further, in the measuring apparatus 100A according to the first modification, the urging means 4 is provided on the upper side of the connecting member 13, so that the moving means 6 is connected to the urging means 4 and the moving member 62. A member 63 is provided. Thus, the U-shaped member 1, the first contact 2, the contact-type displacement meter 3, the biasing means 4, and the displacement meter 5 are moved along the axis of the tube P by moving the moving member 62 in the axial direction of the tube P. It is possible to move integrally in the direction.

  As shown in FIG. 2 (b), the measuring device 100B according to the second modification is different from the measuring device 100 shown in FIG. 1 (a) in that the first arm portion 11 and the first contact 2 are the second. It is provided above the arm portion 12 and the contact displacement meter 3. For this reason, the spring 42 of the biasing means 4 is attached in a state longer than the natural length. As a result, a downward urging force F acts on the connecting member 13 and thus the U-shaped member 1, and the first contact 2 attached to the first arm portion 11 comes into contact with the inner surface of the pipe P. Become.

  As shown in FIG. 2 (c), the measuring device 100C according to the third modification is different from the measuring device 100 shown in FIG. 1 (a) in that the first arm portion 11 and the first contactor 2 are the second ones. It is provided above the arm portion 12 and the contact displacement meter 3. Further, unlike the measuring apparatus 100 shown in FIG. 1A, the measuring apparatus 100 </ b> C according to the third modification is provided with the biasing means 4 on the upper side of the connecting member 13. The spring 42 of the urging means 4 is attached in a state shorter than the natural length, like the measuring device 100 shown in FIG. As a result, a downward urging force F acts on the connecting member 13 and thus the U-shaped member 1, and the first contact 2 attached to the first arm portion 11 comes into contact with the inner surface of the pipe P. Become. Further, in the measuring apparatus 100C according to the third modification, the urging means 4 is provided on the upper side of the connecting member 13, so that the moving means 6 is connected to the urging means 4 and the moving member 62. A member 63 is provided. Thus, the U-shaped member 1, the first contact 2, the contact-type displacement meter 3, the biasing means 4, and the displacement meter 5 are moved along the axis of the tube P by moving the moving member 62 in the axial direction of the tube P. It is possible to move integrally in the direction.

  The measurement apparatus 100A shown in FIG. 1A is also obtained by the measurement apparatus 100A according to the first modification described above, the measurement apparatus 100B according to the second modification, and the measurement apparatus 100C according to the third modification. Similarly, the thickness and the displacement of the inner and outer surfaces of the tube P can be measured efficiently, and as a result, the undulation of the inner and outer surfaces of the tube P can be evaluated.

FIG. 3 shows an example of the result of measuring the pipe end portion of a seamless pipe having an outer diameter of 110 mm and a wall thickness of 10 mm that has been cold-worked after pipe-making by the Eugene Sejurune method using the measuring apparatus 100 shown in FIG. FIG. FIG. 4 is a diagram illustrating an example of a result of measuring a pipe end portion of another seamless pipe having the same specification. Note that the outer surface displacement and the inner surface displacement shown on the vertical axis in FIGS. 3A and 3B and FIGS. 4A and 4B are such that the displacement at the measurement start point (the origin of the horizontal axis) is 0 mm. Shows the value when the constant B shown in the equations (2) and (3) is determined.
As shown in FIGS. 3 and 4, according to the measuring apparatus 100 according to the present embodiment, it is possible to evaluate the thickness of the seamless pipe and the undulation of the inner and outer surfaces.

FIG. 5 is a diagram showing an example of the result of measuring the wall thickness of a seamless pipe having an outer diameter of 73 mm and a wall thickness of 6.6 mm manufactured by a small experimental mill using the measuring apparatus 100 shown in FIG. Specifically, FIG. 5 is a diagram in which piped seamless pipes are cut at appropriate positions in the axial direction, and the thicknesses measured at a pitch of 5 mm in the axial direction are connected for each cut seamless pipe. It is a thing. Fig.5 (a)-FIG.5 (h) each show the result of having measured the thickness about eight different site | parts spaced at equal intervals in the circumferential direction of the seamless pipe.
As shown in FIG. 5, according to the measuring apparatus 100 according to the present embodiment, accurate wall thickness data can be obtained in the axial direction and the circumferential direction of the pipe even when the scale is formed on the surface of the seamless pipe. Since it is possible to measure easily and in large quantities, frequency analysis such as Fourier analysis can be easily performed. Moreover, since the member (the 1st arm part 11 and the 1st contactor 2) inserted in a pipe | tube is simplified, the measuring apparatus 100 which concerns on this embodiment is a pipe | tube with a small internal diameter manufactured with the small experiment mill. Even if it is, the thickness and inner / outer surface displacement can be measured.

DESCRIPTION OF SYMBOLS 1 ... U-shaped member 2 ... 1st contactor 3 ... Contact-type displacement meter 4 ... Biasing means 5 ... Displacement meter 6 ... Moving means 7 ... Calculation means 8 ... Holding means 11 ... 1st arm part 12 ... 2nd arm part 13 ... Connection member 31 ... Shaft member 32 ... 2nd contactor 100 ... Thickness of a pipe | tube And inner / outer surface displacement measuring device (measuring device)
P ... Tube

Claims (2)

A U-shaped member having a first arm part and a second arm part arranged in parallel to face the first arm part, and having one end side of the first arm part and the second arm part connected to each other; ,
A first contact attached to the first arm portion so as to face the second arm portion on the open end side of the U-shaped member;
On the open end side of the U-shaped member, the shaft member is attached to the second arm portion so as to face the first contactor, and can be moved forward and backward in the facing direction, and attached to the tip of the shaft member. A contact-type displacement meter for measuring the displacement of the second contact according to the amount of advancement and retraction of the shaft member;
The first arm portion is located inside the tube, the second arm portion is located outside the tube, and the first arm portion and the second arm portion are substantially in the axial direction of the tube. When the U-shaped member is arranged so as to be parallel, the U-shaped member is arranged so that the first contact attached to the first arm portion contacts the inner surface of the tube. An urging means for urging the first arm portion and the second arm portion in an opposing direction;
A displacement meter for measuring the displacement in the biasing direction of the U-shaped member;
Moving means for relatively moving the U-shaped member, the first contactor, the contact displacement meter, the biasing means, and the displacement meter integrally in the axial direction of the tube;
The thickness of the tube is calculated based on the displacement measurement value by the contact displacement meter, the displacement of the inner surface of the tube is calculated based on the displacement measurement value by the displacement meter, the displacement measurement value by the contact displacement meter and the A calculation means for calculating a displacement of the outer surface of the pipe based on a displacement measurement value by a displacement meter;
An apparatus for measuring the thickness and inner / outer surface displacement of a tube. The arithmetic means sets the displacement measurement value by the contact displacement meter when the calibration material having a thickness A is sandwiched between the first contact and the second contact as UO _0, and the first contact a displacement value measured by the contact type displacement gauge in a state in which the child is the contact and the second contact on the inner surface of the tube in contact with the outer surface of the tube and UO _n, UI _n a displacement value measured by the displacement meter The tube according to claim 1, wherein the thickness of the tube, the displacement of the inner surface of the tube, and the displacement of the outer surface of the tube are calculated by the following formulas (1) to (3). Thickness and inner / outer surface displacement measuring device.
Tube thickness = UO _n −UO ₀ + A (1)
Displacement of the inner surface of the tube = UI _n −B (2)
Displacement of the outer surface of the pipe = UI _n −B + UO _n −UO ₀ + A (3)
However, B in the above formulas (2) and (3) means an arbitrary constant. The displacement measurement value by the contact displacement meter is increased when the second contact is displaced in a direction away from the first contact.

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