JP2014021061A - Reduced-thickness inspection device for piping with thermal insulation material using radioactive isotope as authentication equipment with display and reduced-thickness inspection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reduced-thickness inspection device of piping with thermal insulation materials using a radioactive isotope as authentication equipment with display capable of finely specifying and detecting the reduced-thickness place of piping and a reduced-thickness inspection method.SOLUTION: The reduced-thickness inspection device of piping 50 with thermal insulation materials constituted of an outer casing 53, a thermal insulation material 52 and a pipe material 51 in this order from the outside includes: a first frame 15 having a plurality of rotary rollers 20 and 21 oppositely arranged with the piping 50 with thermal insulation materials sandwiched therebetween, which is mounted on the piping 50 with thermal insulation materials so as to be rotatable in a circumferential direction by allowing the rollers 20 and 21 to abut to the outer peripheral surface of the outer casing 53; a second frame 16 mounted on the first frame 15 so as to slide in a direction orthogonal to the axial center line of the piping 50 with thermal insulation materials, the second frame 16 being constituted such that a radiation source 13 and a radiation detector 14 are oppositely arranged with the piping 50 with thermal insulation materials sandwiched therebetween; and a thickness measurement section 30 for measuring the reduced-thickness of the piping 51 from transmitted radiation amounts to be emitted from the radiation source 13, and to be obtained by the radiation detector 14.

Description

  The present invention relates to a thinning inspection apparatus and a thinning inspection method for a pipe with a heat insulating material using a radioisotope that is an authentication device with a display, and in particular, to a pipe with a heat insulating material whose outside is covered with a heat insulating material. The present invention relates to a thinning inspection apparatus and a thinning inspection method for a pipe with a heat insulating material using a radioisotope, which is an authentication device with a display for measuring a thinning thickness.

  Some pipes used in various plants are covered with a heat insulating material in order to convey a high-temperature or low-temperature liquid or gas.

  In such a pipe with a heat insulating material, when it is attempted to check the deterioration of the pipe by periodic inspection, etc., after removing the heat insulating material, the pipe thickness measurement using an ultrasonic inspection or an ultrasonic inspection is performed. (For example, see Patent Document 1).

  However, before the inspection, the conventional method of removing the heat insulating material first requires the heat insulating material to be repaired after the inspection, so that there is a problem that the inspection takes more cost and time than the case without the heat insulating material. there were. For this reason, it has been worried that pipes with heat insulating materials have a low inspection implementation rate, and that serious damage such as corrosion thinning is often overlooked.

  Thus, there is a radiation inspection apparatus that can indirectly inspect a pipe whose outside is covered with a heat insulating material, but its use has not progressed due to the complexity of legal procedures and the limitation of radiation shielding.

  In addition, in conventional inspection equipment using radiation, the radiation source and detector were slid in the direction intersecting the axial center line of the pipe to measure the amount of radiation absorbed on both sides of the pipe. It was unclear whether the thickness was reduced (for example, see Patent Document 2).

Japanese Unexamined Patent Publication No. 2000-88824. JP-A-60-257308.

  As described above, in the pipe wall thickness measurement using the ultrasonic probe as in the invention described in Patent Document 1, after the heat insulating material is removed, the appearance inspection and the measurement by the ultrasonic probe are not performed. Therefore, there is a problem that the inspection is costly and time consuming.

  On the other hand, in pipe thickness measurement using radiation, there are many legal restrictions such as procedures for the use of radioactivity and management of radiation exposure, and as in the invention described in Patent Document 2, in the inspection apparatus using radiation, There was a problem that it was difficult to determine which side of both sides of the pipe was thin.

  Therefore, there is a technical problem to be solved in order to provide a thinning inspection device and a thinning inspection method for a pipe with a heat insulating material capable of more specifically identifying and detecting a thinning portion of the pipe, The present invention aims to solve this problem.

  The present invention has been proposed in order to achieve the above object, and the invention according to claim 1 is a thinning inspection apparatus for a pipe with a heat insulating material, which is composed of an exterior plate, a heat insulating material, and a tube material in this order from the outside. And having a plurality of rotating rollers arranged opposite to each other across the pipe with the heat insulating material, and contacting the rotating roller with the outer peripheral surface of the exterior plate to the pipe with the heat insulating material A first frame that is rotatably attached to the circumferential direction, a second frame that is slidably attached to the first frame in a direction that intersects the axial center line of the pipe with the heat retaining material, A radiation source and a high-sensitivity γ radiation detector, for example, a CsI (TI) scintillation detector (hereinafter abbreviated as a radiation detector) are arranged opposite to each other with the heat insulating material pipe interposed between the two frames, and the radiation source exits from the radiation source. The amount of transmitted radiation obtained by the radiation detector Further, a thinning inspection apparatus for a pipe with a heat insulating material using a radioisotope, which is an authentication device with a display, including a thickness measuring unit for measuring the thickness reduction of the pipe material.

According to this configuration, when the first frame and the second frame are integrally rotated in the circumferential direction of the pipe with the heat insulating material on the outer peripheral surface of the pipe with the heat insulating material, the radiation source and the radiation detector are It is rotationally scanned around the axis center line of the pipe with the heat insulating material. In addition, when the second frame is slid with respect to the first frame with reference to the axial center line of the pipe with the heat insulating material, the radiation source and the radiation detector move in parallel with each other, and the axial center of the pipe with the heat insulating material It is slid by a certain distance in the direction intersecting with the line and rotated and scanned. Then, in the thickness measurement unit, the transmitted radiation dose at the location where the thinning obtained at the rotational scanning is compared with the transmitted radiation dose at the location where the thinning does not exist, and the second frame is slid by a certain distance. By comparing the amount of transmitted radiation at the location where thinning is obtained and the amount of transmitted radiation at the location where there is no thinning, the extent of thickness reduction of which part of the tube material is obtained. It is possible to determine the thinning state of the pipe material.

  According to a second aspect of the present invention, in the configuration of the first aspect, the first frame and the second frame are arranged to face each other according to an outer diameter of the pipe with the heat insulating material. Provided is a thinning inspection apparatus for a pipe with a heat insulating material using a radioisotope, which is an authentication device with a display formed by adjusting a distance between rotating rollers and a distance between the radiation source and the radiation detector. .

  According to this configuration, when the outer diameter of the heat retaining material-attached pipe changes, the distance between the rotating rollers and the distance between the radiation source and the radiation detector can be adjusted. Thereby, it can respond even if the outer diameter of piping with a heat insulating material changes.

  According to a third aspect of the present invention, in the configuration according to the first or second aspect, at least two or more radiation detectors that receive radiation from the same radiation source are shifted in the circumferential direction of the pipe with the heat insulating material. Provided is a thinning inspection apparatus for a pipe with a heat insulating material using a radioisotope that is an authentication apparatus with a display provided.

  According to this configuration, by providing at least two radiation detectors shifted in the circumferential direction of the pipe with the heat insulating material, it is possible to simultaneously measure the thinning state of different portions of the pipe material in one measurement. .

  According to a fourth aspect of the present invention, in the configuration of the first or second aspect, the radiation detector that receives the radiation from the same radiation source is positioned so as to be along the axial center line of the pipe with the heat insulating material. Provided is a thinning inspection apparatus for a pipe with a heat insulating material using a radioisotope, which is an authentication apparatus with a display provided by shifting at least two.

  According to this configuration, by providing at least two radiation detectors with the positions shifted along the axial center line of the pipe with the heat insulating material, the thinning state of different portions of the pipe material can be simultaneously measured in one measurement. Can be measured.

  The invention according to claim 5 is a thinning inspection method for a pipe with a heat insulating material configured in the order of an exterior plate, a heat insulating material, and a pipe material from the outside, and a radiation source and a radiation detection across the pipe with the heat insulating material The radiation source and the radiation detector are arranged so as to face each other, and the slide operation in the direction intersecting the central axis of the pipe with the heat insulating material and the rotation operation in the circumferential direction are performed. A thinning inspection method for a pipe with a heat insulating material using a radioisotope, which is an authentication device with a display for measuring the thinning thickness of the pipe from the amount of transmitted radiation obtained by the radiation detector.

  According to this method, when the radiation source and the radiation detector are rotated on the outer peripheral surface of the pipe with the heat insulating material, the rotation scanning is performed around the axial center line of the pipe with the heat insulating material. In addition, when the radiation source and the radiation detector are translated from, for example, the axis center of the pipe with the heat insulating material toward the pipe end surface, the radiation source and the radiation detector are constant in the direction intersecting the axis center line of the pipe with the heat insulating material. It is slid by the distance and rotated and scanned. Then, the transmitted radiation dose at the location where the thinning is obtained and the transmitted radiation dose at the location where the thinning is not obtained are compared, and the second frame is slid by a predetermined distance and rotationally scanned. By comparing the amount of transmitted radiation at the location where the thinning is present and the amount of transmitted radiation at the location where there is no thinning, including how much of the surface of the tubular material is thinned, A thinning state can be determined.

  According to the first aspect of the present invention, the radiation dose obtained by rotational scanning of the radiation source and the radiation detector around the axial center line of the pipe with the heat insulating material, and the axial center of the pipe with the heat insulating material are provided. Based on the amount of transmitted radiation obtained by sliding scanning in the direction intersecting the line, the thinned part of the pipe material is specified in detail, including how much the surface of the pipe material is thinned in the wall thickness measurement unit Therefore, there is an expectation that an accurate detection can be easily performed.

  In addition to the effect of the first aspect, the invention according to the second aspect can be used according to the outer diameter even if the outer diameter of the pipe with the hot material changes, so that versatility is obtained. The advantage is expected.

  In addition to the effect of the first or second aspect, the invention according to the third aspect can simultaneously measure the thinning state of different parts of the pipe material by one measurement, so that the measurement time can be shortened and the measurement accuracy can be reduced. Improvement is expected.

  In addition to the effect of the first or second aspect, the invention according to the fourth aspect can further reduce the measurement time and the measurement accuracy because the thinning state of different parts of the pipe material can be simultaneously measured by one measurement. Improvement is expected.

  The invention according to claim 5 is the amount of transmitted radiation obtained by rotating and scanning the radiation source and the radiation detector around the axial center line of the piping with the heat insulating material, and the axial center of the piping with the thermal insulating material between the radiation source and the radiation detector. Based on the amount of transmitted radiation obtained by sliding scanning in the direction intersecting with the line, the thinned part of the pipe material, including the degree of thinning of the surface of which part of the pipe material, should be specified in more detail and detected. Therefore, there is an expectation that an accurate detection can be easily performed.

BRIEF DESCRIPTION OF THE DRAWINGS It is a front view of the thinning inspection apparatus shown as 1st Embodiment of this invention, (a) is a figure which shows the state which installed the piping with a heat insulating material of a standard outer diameter, (b) is outside smaller than a standard. The figure explaining the response | compatibility at the time of installing the piping with a heat insulating material of a diameter, (c) is the figure explaining the slide scanning at the time of installing the piping with a heat insulating material of a standard outer diameter. The side view of the thinning inspection apparatus shown as 1st Embodiment of this invention. It is a top view of the thinning inspection apparatus shown as 1st Embodiment of this invention, (a) is a figure which shows the state before a slide scan, (b) is a figure explaining a slide scan. It is a figure explaining the thinning measurement of the thinning inspection apparatus shown as 1st Embodiment of this invention, (a) is explanatory drawing of the measurement by rotational scanning, (b) is explanatory drawing of the measurement by slide scanning. The figure which shows an example of the count value change obtained by the thinning measurement of the rotation scanning in the thinning inspection apparatus shown as 1st Embodiment of this invention. The front view of the thinning inspection apparatus shown as 2nd Embodiment of this invention. The side view of the thinning inspection apparatus shown as 2nd Embodiment of this invention. The top view of the thinning inspection apparatus shown as 2nd Embodiment of this invention. The front view of the thinning inspection apparatus shown as 3rd Embodiment of this invention. The side view of the thinning inspection apparatus shown as 3rd Embodiment of this invention. The top view of the thinning inspection apparatus shown as 3rd Embodiment of this invention. The figure explaining the thinning measurement of the thinning inspection apparatus shown as the first embodiment of the present invention is a diagram illustrating two places of piping obtained when the radiation source-radiation detector is slid from the axial center line of the piping and rotated and scanned. The relationship of the measurement site for thinning is shown.

  An object of the present invention is to provide a thinning inspection apparatus and a thinning inspection method for a pipe with a heat insulating material using a radioisotope, which is an authentication device with a display capable of more specifically identifying and detecting a thinning portion of the pipe. In order to achieve this, it is a thinning inspection device for a pipe with a heat insulating material, which is composed of an exterior plate, a heat insulating material, and a pipe material in this order from the outside, and is arranged opposite to each other across the pipe with the heat insulating material. A first frame that is attached to the outer peripheral surface of the exterior plate so as to be rotatable in a circumferential direction with respect to the pipe with the heat insulating material; A second frame that is slidably attached to the frame in a direction intersecting the axis center line of the pipe with the heat insulating material, and a radiation source and a radiation detector sandwiching the pipe with the heat insulating material between the second frame. Placed facing each other and out of the radiation source Serial from penetrating radiation amount obtained by the radiation detector is realized so as to include a wall-thickness measurement section for measuring the thickness reduction of the pipe material.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as “embodiments”) will be described in detail with reference to the accompanying drawings. In the description of the present invention, expressions indicating directions such as up and down and left and right are relative rather than absolute, and are appropriate when each part of the thinning inspection apparatus of the present invention is drawn. However, if the posture changes, it should be interpreted according to the change in posture.

  1 to 3 show a first embodiment of a thinning inspection apparatus according to the present invention. FIG. 1 is a front view of the thinning inspection apparatus, FIG. 2 is a side view of the thinning inspection apparatus, and FIG. FIG. 3 is a top view of the thinning inspection apparatus. In the following description, the left-right direction of FIG. 1A is the left-right direction of the thinning inspection apparatus, the up-down direction is the up-down direction, the direction perpendicular to the page is the axial direction, and the direction indicated by the arrow 100 is the circumferential direction (or rotational scanning direction) The direction indicated by the arrow 101 will be described as the slide direction.

  1 to 3, the thinning inspection apparatus 11 has a pipe fixing frame 12 installed on the outer peripheral surface of a pipe 50 with a heat insulating material, which is a pipe to be measured that is laid horizontally, and the pipe fixing frame. A radiation source 13 and a radiation detector 14 are attached to 12. The radiation source 13 used here is a radioisotope, which is an authentication device with a minute dose display that is not restricted in use.

  As shown in FIG. 4, the pipe 50 with a heat insulating material, which is a pipe to be measured, covers the outer periphery of an iron pipe 51 manufactured based on Japanese Industrial Standard (JIS) or the like with a heat insulating material 52 such as calcium silicate. Further, the outer periphery of the heat insulating material 52 is covered with an outer plate 53 made of iron or stainless steel. In this embodiment, the outer diameter of the tube material 51 is 150 A, the thickness is 5 mm, the thickness of the heat insulating material 52 is 50 mm, and the thickness of the exterior plate 53 is 0.3 mm.

  The pipe fixing frame 12 includes a first frame 15 and a second frame 16.

  The first frame 15 includes an upper frame portion 15a, a side frame portion 15b suspended from one end side of the upper frame portion 15a, and a relative position to the upper frame portion 15a from the lower end side of the side frame portion 15b. The lower frame portion 15c, which is attached to the side frame portion 15b so as to be vertically slidable so as to extend in parallel with the lower frame portion 15b, is integrally formed so as to be substantially U-shaped when viewed from the front.

  A roller attachment member 18 is attached to the lower frame portion 15 c via a height adjustment member 17. The height adjusting member 17 is a rod-like screw member screwed in a state of passing through a screw hole (not shown) of the lower frame portion 15c, and a roller attachment member 18 is rotatably attached to an upper end portion thereof. A knob 19 is attached to the part so as to be integrally rotatable. Then, when the knob 19 is picked and rotated, the height adjusting member 17 is screwed up or down depending on the rotation direction by screwing with the screw hole of the lower frame portion 15c. Accordingly, the roller mounting member 18 can move upward or downward with respect to the lower frame portion 15c.

  Further, a pair of rotating rollers 20, 20 are attached to the roller mounting member 18 so as to be rotatable in a state in which they can contact the outer peripheral surface (exterior plate 53) of the pipe 50 with a heat insulating material. Yes. The pair of rotating rollers 21 and 21 are separated from each other on the lower surface side of the upper frame portion 15a so as to face the pair of rotating rollers 20 and 20, and the outer peripheral surface of the pipe 50 with the heat insulating material. It is rotatably attached so as to be able to contact the (exterior plate 53).

  Then, in a temporary set state in which the pair of rotating rollers 20, 20 are in contact with the outer peripheral surface (exterior plate 53) of the heat retaining material-equipped pipe 50, the height adjusting member 17 is adjusted, and the pair of roller rotations 20. When the roller mounting member 18 is moved upward until the outer peripheral surface of the pipe 50 with a heat insulating material contacts the outer peripheral surface of the pipe 50 with a heat insulating material, the axial center O of the pipe 50 with the heat insulating material is disposed between the pair of rotating rollers 20, 20. At the same time, the piping 50 with a heat insulating material is held between the pair of rotating rollers 21 and 21 and the pair of rotating rollers 20 and 20, and the first frame 15 is held by the holding by the holding. It can be attached to the outer peripheral surface (exterior plate 53) of the attached pipe 50. FIG. 1A shows a state in which the pipe fixing frame 12 is attached to the outer peripheral surface of the heat retaining material-equipped pipe 50 in this way.

  In addition, when the thickness (outer diameter) of the pipe 50 with a heat insulating material is smaller than the thickness of the standard pipe 50 with a heat insulating material, the position of the lower frame portion 15c is moved upward with respect to the side frame 15b. After that, the height adjusting member 17 may be adjusted. On the other hand, if the thickness of the standard heat insulating material pipe 50 is larger, the height adjusting member 17 is adjusted after the position of the lower frame portion 15c is moved downward with respect to the side frame 15b. May be.

  Next, the second frame 16 has an upper frame portion 16a attached to the upper frame portion 15a of the first frame 15 so as to be slidable in the horizontal direction, and is suspended from one end side of the upper frame portion 16a. The side frame portion 16b is attached to the side frame portion 16b so as to be vertically slidable so as to extend parallel to the upper frame portion 16a from the lower end side of the side frame portion 16b. The lower frame portion 16c is integrally formed and is formed in a generally U shape in front view. Therefore, the second frame 16 is attached to the upper frame portion 15a of the first frame 15 in a horizontal direction with respect to the first frame 15 by attaching the upper frame portion 16a to be horizontally movable. It can slide in the direction of arrow 101 in FIG.

  The radiation detector 14 is fixedly attached to the lower surface of the upper frame portion 16a of the second frame 16, and the upper surface of the lower frame portion 16c is opposed to the radiation detector 14. The radiation source 13 is fixedly attached. The radiation source 13 and the radiation detector 14 scan the radiation emitted from the radiation source 13 against the heat retaining material-equipped pipe 50 and detect the amount of transmitted radiation at that time by the radiation detector 14. It is. Then, the amount of transmitted radiation detected by the radiation detector 14 is sent to the wall thickness measurement unit 30, and the wall thickness measurement unit 30 reduces the wall thickness of the pipe material 51 based on the signal from the radiation detector 14. It comes to measure.

  Next, the operation of the thinning inspection apparatus 11 according to the present invention will be described. First, when the pipe fixing frame 12 is set in the pipe 50 with a heat insulating material, in the first frame 15, a gap between the pair of rotating rollers 20, 20 and the pair of rotating rollers 21, 21. The height adjusting member 17 is adjusted until the distance between the pair of rotating rollers 20 and 20 moves downward until the distance between the pair of rotating rollers 20 and 20 increases. On the other hand, in the second frame 16, the gap between the radiation source 13 and the radiation detector 14 is in a state separated by a predetermined amount larger than the outer diameter of the pipe 50 with a heat insulating material. The position of the lower frame portion 16c with respect to the side frame portion 16b is adjusted.

  That is, when the thickness (outer diameter) of the pipe 50 with the heat insulating material is smaller than the thickness of the standard pipe 50 with the heat insulating material, the position of the lower frame portion 15 c is set to the side frame in the first frame 15. After adjusting the movement upward with respect to 15b, the height adjusting member 17 is further adjusted. On the other hand, in the second frame 16, the position of the lower frame portion 16c is moved and adjusted upward with respect to the side frame 16b, and the gap between the radiation source 13 and the radiation detector 14 is set in a predetermined state. Adjust to. FIG. 1 (a) shows a case of the pipe 50 with a standard thickness of the heat insulating material, and FIG. 1 (b) shows a case where the pipe is smaller than the standard thickness.

  On the other hand, when the thickness of the pipe 50 with the heat insulating material is larger than the thickness of the standard pipe 50 with the heat insulating material, the position of the lower frame portion 15c is set to the side frame in the first frame 15. After adjusting the movement downward with respect to 15b, the height adjusting member 17 is further adjusted. On the other hand, in the second frame 16, the position of the lower frame portion 16c is moved and adjusted downward with respect to the side frame 16b, and a gap between the radiation source 13 and the radiation detector 14 is set to a predetermined value. Adjust to the state.

  Next, in the temporary setting state, the height adjusting member 17 is adjusted, and the roller mounting member 18 is moved upward until the pair of roller rotations 20 and 20 abut on the outer peripheral surface of the heat retaining material-equipped pipe 50. Thereby, the axial center O of the pipe 50 with the heat insulating material is positioned between the pair of rotating rollers 20 and 20, and between the pair of rotating rollers 21 and 21 and the pair of rotating rollers 20 and 20. The piping 50 with a heat insulating material is sandwiched and held. Further, by this holding, the first frame 15 can be attached to the outer peripheral surface of the pipe 50 with a heat insulating material together with the second frame 16.

  In this way, the first frame 15 attached to the outer peripheral surface of the pipe 50 with a heat insulating material together with the second frame 16 is provided via the pair of rotating rollers 20 and 20 and the pair of rotating rollers 21 and 21. Are attached to the pipe 50 with a heat insulating material, and the circumferential direction of the pipe 50 with a heat insulating material (in FIG. 1) is accompanied by the rotation of the pair of rotating rollers 20 and 20 and the pair of rotating rollers 21 and 21. In the direction of the arrow 100 shown in FIG.

  In the thinning inspection apparatus 11 attached to the outer peripheral surface of the pipe 50 with a heat insulating material in this way, at the start of measurement, the center of the radiation source 13 and the center of the radiation detector 14 are the pipe with the heat insulating material. It is set to pass 50 axial centers O.

  Further, with the rotation of the pair of rotating rollers 20 and 20 and the pair of rotating rollers 21 and 21, the pipe fixing frame 12 is moved in the circumferential direction of the pipe 50 with the heat insulating material (indicated by the arrow 100 shown in FIG. 1). When rotating in the direction), scanning in the rotational direction of the radiation source 13 and the radiation detector 14 with respect to the pipe 50 with heat insulating material is performed. At this time, different radiation doses are obtained from the radiation detector 14 in accordance with the thinned state of the tube material 51, and this is output to the wall thickness measurement unit 30. FIG. 5 shows the change in the count value obtained when scanning from 0 ° to 180 ° by this rotational scanning, and the amount of transmitted radiation increases in the thinned portion. That is, the amount of transmitted radiation increases in the vicinity of 60 ° to 110 ° and 150 ° in FIG. Based on this count value change, the thickness measuring unit 30 determines at which rotational position the portion is in a reduced thickness state.

  However, in this state, it is unclear which side is still thinning. Therefore, subsequently, the second frame 16 is slid with respect to the first frame 15. In this slide, the radiation source 13 and the radiation detector 14 are moved in parallel from the axial center O of the heat retaining material-equipped pipe 50 toward the pipe end face. Scan. In the rotational scanning performed by sliding the second frame by a predetermined distance, the center of the radiation source 13 and the center of the radiation detector 14 are set so as to pass through the axial center O of the pipe 50 with a heat insulating material. A transmitted radiation dose corresponding to the thinning state of the tube material 51 different from that at the time of the rotational scanning obtained from the detector 14 is obtained, and this is output to the thickness measuring unit 30.

  The thickness measurement unit 30 compares the change in transmitted radiation amount obtained by rotational scanning with the change in transmitted radiation obtained by rotational scanning by sliding a predetermined distance, and compares The thinning state of the pipe material 51 is determined including how much of which side surface is thinned.

  The determination principle will be described. First, the radiation source 13 and the radiation detector 14 are rotated in the circumferential direction with respect to the axial center O of the pipe 50 with a heat insulating material in order to detect a thinned portion. The radiation emitted from the radiation source 13 passes through the axial center O and enters the radiation detector 14. The amount of radiation obtained at this time is proportional to the amount of radiation that has passed through the two side surfaces of the exterior plate 53, the heat insulating material 52, and the tube material 51 existing between the radiation source 13 and the radiation detector 14. Here, since the exterior plate 53, the heat insulating material 52, and the tube material 51 are designed with a constant thickness, the radiation dose when rotated 180 ° is the same radiation dose over 180 °. If there is a place where the pipe material 51 is thinned, the amount of radiation absorbed there decreases, so the radiation amount measured by the radiation detector 14 increases at the thinned portion. By detecting this increase, the presence or absence of thinning can be determined.

  However, since the measurement here is the sum of the absorption of the two side surfaces of the pipe material 51 in the path through which the radiation passes, it is necessary to determine which side surface has the thinning. Therefore, it can be determined by changing the combination of the two locations of the pipe material 51 through which the radiation passes.

  Therefore, with respect to the rotational scanning performed by setting the center of the radiation source 13 and the center of the radiation detector 14 so as to pass through the axial center O of the tube material 51, The second frame 16 is slid by a certain distance. By this slide, the radiation source 13 and the radiation detector 14 are also slid to a place away from the axial center line O by a certain distance. Thereby, the location of two points of the pipe material 51 on the path | route in which the radiation emitted from the said radiation source 13 injects into the said radiation detector 14 can be changed. When rotating in the circumferential direction of the pipe 50 with a heat insulating material in this state, two points of the pipe material 51 on the path where the radiation emitted from the radiation source 13 passes through the axial center line and enters the radiation detector 14. Unlike the measurement of the amount of radiation absorbed at the location, it is possible to measure the amount of radiation absorbed through different points.

  For example, if the two points in the case of radiation passing through the axial center O are A and B, the combination of the two points when sliding is A and C. When this combination is rotated 180 ° and the amount of transmitted radiation is measured, it can be determined where the thinning is present. If there is an increase in radiation dose at location A in the above two measurements, the thinning can be determined as A, and if the increase is observed in one measurement, it can be determined as other location B or C.

  Therefore, in this thinning inspection apparatus 11, the amount of transmitted radiation that can be obtained by the radiation detector 14 when the radiation source 13 is rotated and scanned on the path incident on the radiation detector 14 through the center line O. And how much of the side surfaces of the both sides of the pipe material 51 are thinned based on the amount of transmitted radiation obtained by sliding and rotating a certain distance from the axial center O of the pipe 50 with heat insulating material. In other words, the thinned portion of the pipe material 51 can be more specifically identified and detected. Further, by using the difference in the amount of transmitted radiation for the measurement, it is possible to use the radiation source 13 of the authentication device with a display with a minute dose with no use limitation.

  6 to 8 show a thinning inspection apparatus as a second embodiment of the present invention. In the second embodiment, three radiation detectors 14, 14, 14 are provided by shifting in the circumferential direction of the pipe 50 with a heat insulating material, and other configurations are the same as those in FIGS. 1 to 3. Therefore, the same components are denoted by the same reference numerals, and redundant description is omitted.

  That is, the thinning inspection apparatus 11 of the second embodiment is provided with one radiation source 13 in the lower frame portion 16c of the second frame 16 as shown in FIG. The three radiation detectors 14, 14, 14 are provided on the lower surface of the upper frame portion 16a so as to be separated from each other in the left-right direction. Of these three radiation detectors 14, 14, 14, the middle radiation detector 14 (A) is configured such that the center of the radiation source 13 and the center of the radiation detector 14 are the axes of the pipe 50 with the heat insulating material. The radiation detectors 14 (B) and 14 (C) on the left and right are set so as to pass through the center O, and are arranged at positions away from the axis center O of the pipe 50 with heat insulating material.

  In the thinning measurement in the thinning inspection apparatus 11 of the second embodiment, the radiation radiated from one radiation source 13 is received by the three radiation detectors 14, 14, and 14, respectively. The transmitted radiation amount detected by the radiation detectors 14, 14, 14 is input to the thickness measuring unit 30 and measured.

  In the thinning inspection apparatus 11 of the second embodiment, the center of the radiation source 13 and at least one center of the radiation detectors 14, 14, 14 are set so as to pass through the axial center O of the tube material 51. Then, rotation scanning for rotating the pipe fixing frame 12 in the circumferential direction of the pipe 50 with heat insulating material, and sliding the second frame 16 with respect to the first frame 15 to make a constant from the axial center O. Rotation scanning that rotates after sliding the distance is performed.

  Then, from the transmitted radiation doses obtained by the two different rotational scans, it is determined which part is in a thinned state by the thickness measuring unit 30.

  Therefore, in the measurement according to the second embodiment, it is possible to simultaneously measure the thinning of a plurality of locations of the pipe material 51 in one measurement, so that the measurement time can be shortened and the measurement accuracy can be improved. In the second embodiment, a structure in which three radiation detectors 14 are arranged by shifting in the circumferential direction of the pipe 50 with a heat insulating material is disclosed. However, two or more radiation detectors 14 may be used. It is good.

  9 to 10 show a thinning inspection apparatus as a third embodiment of the present invention. In the third embodiment, three radiation detectors 14, 14, 14 are provided by shifting their positions along the axis of the axis center O of the pipe 50 with a heat insulating material, and other configurations are as follows. Since it is the same as FIG. 1 thru | or FIG. 3, the same component is attached | subjected the same code | symbol and duplication description is abbreviate | omitted.

  That is, in the thinning inspection apparatus 11 of the third embodiment, as shown in FIGS. 10 and 11, one radiation source 13 is provided in the lower frame portion 16 c of the second frame 16, and the second frame The three radiation detectors 14, 14, 14 are provided on the lower surface of the upper frame portion 16 a of 16 so as to be displaced from each other along the axis of the axis center O of the pipe 50 with a heat insulating material.

  In the thinning measurement in the thinning inspection apparatus 11 of the third embodiment, the radiation radiated from one radiation source 13 is received by the three radiation detectors 14, 14, and 14, respectively. The transmitted radiation amount detected by the radiation detectors 14, 14, 14 is input to the thickness measuring unit 30 and measured.

  In the thinning inspection apparatus 11 of the third embodiment, the center of the radiation source 13 and the centers of the radiation detectors 14, 14, 14 are set so as to pass through the axial center O of the tube material 51. Rotation scanning in which the pipe fixing frame 12 is rotated in the circumferential direction of the pipe 50 with a heat insulating material, and the second frame 16 is slid with respect to the first frame 15 and is slid a predetermined distance from the axis O. Rotation scanning is performed after rotation.

  Then, from the transmitted radiation doses obtained by the two different rotational scans, it is determined which part is in a thinned state by the thickness measuring unit 30.

  Therefore, in the measurement according to the third embodiment, it is possible to simultaneously measure the thinning of a plurality of locations of the pipe material 51 by one measurement, so that the measurement time can be shortened and the measurement accuracy can be improved. In the third embodiment, a structure in which three radiation detectors 14 are disposed so as to be shifted along the axial center line of the pipe 50 with a heat insulating material is disclosed. However, two or more radiation detectors are disclosed. The container 14 is sufficient.

  In each example of the second and third embodiments, one of the three radiation detectors 14, 14, 14 is the center of the radiation source 13 and the center of the radiation detector 14 during rotational scanning. Is set so as to pass through the axial center O of the pipe 50 with a heat insulating material. For example, as shown in FIG. 12, all the radiations directed toward the radiation detectors 14, 14, and 14 are By passing through a place away from the axial center O of the pipe 50 with material, it is possible to easily distinguish on which side of the pipe material 51 the thinning is present.

  It should be noted that the present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

  The present invention can also be applied to a pipe thickness reduction inspection apparatus that measures a thickness reduction other than a pipe with a heat insulating material covered with a heat insulating material.

11 Thinning Inspection Device 12 Pipe Fixing Frame 13 Radiation Source 14 Radiation Detector 15 First Frame 15a Upper Frame Part 15b Side Frame Part 15c Lower Frame Part 16 Second Frame 16a Upper Frame Part 16b Side Frame Part 16c Lower Frame Portion 17 Height adjusting member 18 Roller mounting member 19 Knob 20 Rotating roller 21 Rotating roller 30 Thickness measuring unit 50 Pipe 51 with heat insulating material Tubing material 52 Heat insulating material 53 Exterior plate 100 Arrow (circumferential direction, rotational scanning direction)
101 arrow (slide direction, slide scan direction)
O axis center

Claims (5)

It is a thinning inspection device for piping with a heat insulating material, which is composed of an exterior plate, a heat insulating material, and a tube material in this order from the outside.
A plurality of rotating rollers disposed opposite to each other with the piping with the heat insulating material interposed therebetween, the circumferential direction of the rotating roller being in contact with the outer peripheral surface of the exterior plate with respect to the piping with the heat insulating material; A first frame rotatably attached to the
A second frame attached to the first frame so as to be slidable in a direction intersecting the axial center line of the pipe with the heat insulating material;
A radiation source and a high-sensitivity γ radiation detector, for example, a CsI (TI) scintillation detector (hereinafter abbreviated as a radiation detector) are arranged opposite to each other with the heat retaining material pipe interposed between the second frame and the radiation source. A wall thickness measuring unit that measures the reduced thickness of the tube from the amount of transmitted radiation obtained from the radiation detector,
A thinning inspection apparatus for a pipe with a heat insulating material using a radioisotope, which is an authentication apparatus with a display.   The first frame and the second frame have a distance between the rotating rollers disposed opposite to each other and between the radiation source and the radiation detector according to an outer diameter of the pipe with the heat insulating material. The thinning inspection apparatus for a pipe with a heat insulating material using a radioisotope, which is an authentication apparatus with a display according to claim 1, wherein the distance is formed so as to be adjustable.   The authentication with a display according to claim 1 or 2, wherein at least two radiation detectors that receive radiation from the same radiation source are provided by being shifted in a circumferential direction of the pipe with the heat insulating material. A thinning inspection device for piping with heat insulation materials using radioactive isotopes.   2. The radiation detector for receiving radiation from the same radiation source, wherein at least two radiation detectors are provided so as to be shifted along the axial center line of the pipe with heat insulating material. A thinning inspection apparatus for pipes with a heat insulating material using a radioisotope, which is an authentication apparatus with a display according to 2. It is a thinning inspection method for a pipe with a heat insulating material composed of an exterior plate, a heat insulating material, and a pipe material in this order from the outside,
A radiation source and a radiation detector are arranged facing each other across the pipe with the heat insulating material, and the radiation source and the radiation detector are slid in the direction intersecting the central axis of the pipe with the heat insulating material and the circumferential direction. A radioisotope which is an authentication device with a display, characterized in that the thinning thickness of the tube material is measured from the amount of transmitted radiation obtained from the radiation source and obtained by the radiation detector. Thinning inspection method for used heat insulating material piping.