JP6601793B2 - Underwater bolt inspection jig and underwater bolt inspection method - Google Patents

Description

  The present invention relates to a jig used in an apparatus for inspecting the soundness of a bolt (for example, an anchor bolt) installed in water, and an inspection method using the jig.

  Anchor bolts installed in water are subject to initial deformation and initial defects due to excessive load during installation, and fatigue cracks and corrosion occur as aging. For this reason, also from the meaning which ensures the safety of the whole structure, it is important to grasp | ascertain the soundness of an anchor bolt non-destructively in water. However, it is difficult to detect the above-described defects by visual inspection of the surface in water or hammering.

  A device disclosed in Patent Document 1 is known as a device that performs non-destructive testing of structures installed in water. In the apparatus disclosed in Patent Document 1, an opening of a container in which an ultrasonic probe is arranged is arranged facing a structure surface, and water is provided between the ultrasonic probe and the structure surface. It is based on interpolation. And in the apparatus currently disclosed by patent document 1, even if it is a case where a structure surface has inclination and an unevenness | corrugation by providing an expansion-contraction mechanism in the side wall of a container, a structure surface and an ultrasonic probe are used. The distance between them can be kept constant.

JP 2008-215877 A

  If it is an apparatus currently disclosed by patent document 1, even if it is the structure installed in water, it is thought that a soundness can be test | inspected efficiently by nondestructiveness. However, in the apparatus disclosed in Patent Document 1, in order to make the distance between the structure to be inspected and the ultrasonic probe constant, it is necessary to adjust the height by an expansion / contraction mechanism for each measurement. For this reason, it is not suitable for inspection of an anchor bolt or the like having a large number of inspection objects and a small area of the inspection object surface.

  Therefore, the present invention provides an underwater bolt inspection jig and an inspection method that can easily maintain a constant distance from a surface to be inspected, can perform a nondestructive inspection efficiently in a short time, and efficiently. With the goal.

  An underwater bolt inspection jig according to the present embodiment for achieving the above object includes a first opening in which an ultrasonic probe is disposed, and the first opening on a straight line of the first opening. And an ultrasonic probe disposed in the first opening and the second opening. The second opening includes a second opening into which an end of a bolt installed in water is inserted. An irrigation region is provided between the bolt and the bolt inserted into the bolt, and a ring-shaped member made of a non-magnetic member is disposed in the irrigation region to adjust the insertion amount of the bolt.

  In the underwater bolt inspection jig having the above-described characteristics, it is preferable that a magnet that is attracted to the bolt end portion is disposed in the irrigation region and on the second opening side. By having such a feature, it is possible to prevent the housing disposed at the bolt end from being displaced due to the influence of water flow or the like. For this reason, the distance between the ultrasonic probe and the surface to be inspected can be kept constant during inspection. Therefore, a highly accurate inspection result can be obtained.

  In the underwater bolt inspection jig having the above-described characteristics, an angle adjusting member that adjusts the insertion angle of the housing with respect to the bolt end portion is provided on the second opening side of the housing. Can do. By having such characteristics, ultrasonic waves can be incident obliquely on the bolt to be inspected. This makes it possible to effectively detect corrosion and scratches on the side surfaces of the bolts.

  In the underwater bolt inspection jig having the above-described characteristics, the second opening may be inserted in a state where the housing is inclined with respect to the bolt. Even in such a case, ultrasonic waves can be incident obliquely on the bolt to be inspected. This makes it possible to effectively detect corrosion and scratches on the side surfaces of the bolts.

Moreover, in the underwater bolt inspection method according to the present invention for achieving the above object, a jig provided with an ultrasonic probe is arranged at an end of a bolt installed in water, and the bolt is provided with the jig. From the ultrasonic probe in a state where water is interposed between the end of the bolt and the ultrasonic probe, the end of An underwater bolt inspection method that outputs ultrasonic waves and performs flaw detection on the bolt, wherein a ring-shaped member made of a non-magnetic member is disposed in the irrigation region of the jig, and the insertion amount of the bolt is adjusted. characterized in that it.

  Further, in the underwater bolt inspection method having the above-described characteristics, the ultrasonic radiation surface of the ultrasonic probe is arranged so as to have an inclination angle with respect to a perpendicular line with the end of the bolt as a base point. The bolt may be flaw-detected. By having such characteristics, ultrasonic waves can be incident obliquely on the bolt to be inspected. This makes it possible to effectively detect corrosion and scratches on the side surfaces of the bolts.

  Further, in the underwater bolt inspection method having the above-described characteristics, it is preferable to perform flaw detection of the bolt while performing communication between a measurement person on the water and an underwater diver through the communication means. By adopting such a method, it is possible to continue the inspection without the necessity of the diver ascending to the surface of the water only by contacting the measurement staff and the diver about completion of measurement, re-measurement, during measurement, etc. it can. Therefore, the inspection efficiency can be improved.

  According to the underwater bolt inspection jig having the above-described features and the inspection method using this inspection jig, it is easy to maintain a constant distance from the surface to be inspected for a short time when inspecting the underwater bolt. Therefore, it is possible to perform nondestructive inspection efficiently with high accuracy.

It is a perspective view of the underwater bolt inspection jig concerning an embodiment. It is a sectional side view of the underwater bolt inspection jig concerning an embodiment. It is a sectional side view which shows the use condition of the underwater bolt inspection jig which concerns on embodiment. It is a graph which shows the reflected wave waveform in the volt | bolt which has a damage | wound of a depth of 24 mm in the position of 50 mm from the incident end surface. It is a graph which shows the reflected wave waveform in the volt | bolt which has a damage | wound of 12 mm depth in the position of 50 mm from the incident end surface. It is a graph which shows the reflected wave waveform in the volt | bolt which has a damage | wound of a depth of 6 mm in the position of 50 mm from the incident end surface. It is a graph which shows the reflected wave waveform in the volt | bolt which has a damage | wound of a depth of 24 mm in the position of 115 mm from the incident end surface. It is a graph which shows the reflected wave waveform in the volt | bolt which has a crack of a depth of 12 mm in the position of 115 mm from the incident end surface. It is a graph which shows the reflected wave waveform in the volt | bolt which has a damage | wound of a depth of 6 mm in the position of 115 mm from the incident end surface. It is a figure which shows a mode that an anchor bolt is continuously inspected in water. It is a figure which shows the 1st application form of an underwater bolt test | inspection jig. It is a figure which shows the 2nd application form of an underwater bolt test | inspection jig.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of an underwater bolt inspection jig and an inspection method of the present invention will be described in detail with reference to the drawings.
The underwater bolt inspection jig (hereinafter simply referred to as inspection jig 10) according to the present embodiment is used by being attached to the ultrasonic probe 30 of the ultrasonic inspection apparatus 28 (see FIG. 10). As shown in FIG. 1, the appearance of the inspection jig 10 is a housing 12 in a form in which cylindrical bodies having different diameters are connected by a truncated cone. A first opening 14 and a second opening 16 are provided at the longitudinal ends of the housing 12, respectively.

  The first opening 14 is a through hole for arranging the ultrasonic probe 30 which is an element constituting the ultrasonic inspection apparatus 28 described above. The 1st opening part 14 should just be the structure which can hold | maintain the ultrasonic radiation site | part of the ultrasonic probe 30 in the state which orient | assigned to internal space.

The 2nd opening part 16 is a through-hole for inserting the edge part of the volt | bolt 40 (anchor bolt) made into a test object. The first opening 14 and the second opening 16 are in communication with each other, and the ultrasonic wave emitted from the ultrasonic probe 30 disposed in the first opening 14 is a bolt inserted from the second opening 16. 40 is incident on the end face.
The first opening 14 and the second opening 16 may each include a holder 18 that matches the diameter of the ultrasonic probe 30.

  A space between the ultrasonic probe 30 and the bolt 40 is an irrigation region 20 filled with water at the time of inspection. On the side of the second opening 16 in the irrigation region 20, a ring-shaped member 22 that determines the amount of bolt 40 to be inserted from the second opening 16 into the housing 12 is disposed. The ring-shaped member 22 is a non-magnetic member, for example, a ring-shaped flat plate made of plastic such as PVC (Polyvinyl Chloride), acrylic, or the like. The ring-shaped member 22 is fixed to a predetermined position of the irrigation region 20 in the housing 12 so that the plate surface is parallel to the second opening 16. The ring is preferably smaller than the diameter of the bolt 40 to be inspected and large enough not to interfere with the ultrasonic inspection. In the present embodiment, the size of the ring is adjusted to the diameter of the ultrasonic probe 30.

  By providing the ring-shaped member 22, the bolt 40 inserted from the second opening 16 can be brought into contact with the ring-shaped member 22 and stopped. Thereby, the insertion amount of the volt | bolt 40 can be kept constant. For this reason, the distance between the ultrasonic probe 30 and the end face of the bolt 40 to be inspected can be made constant, and the inspection can be performed efficiently.

  In the irrigation region 20 adjacent to the ring-shaped member 22, a magnet 24 is provided on the side where the ultrasonic probe 30 is disposed. The magnet 24 may be a cylindrical shape or a chip shape arranged along the inner surface of the housing 12.

  By setting it as such a structure, the volt | bolt 40 comprised with the magnetic body can be adsorb | sucked. Therefore, if the bolt 40 to be inspected is made of a magnetic material, the housing 12 can be semi-fixed by a magnetic force with the end of the bolt 40 inserted from the second opening 16. For this reason, it is possible to prevent the housing 12 from being displaced or detached during the inspection, and it is possible to perform stable data measurement and to perform a highly accurate inspection.

  Further, in the inspection jig 10 according to the present embodiment, the through hole 26 is formed on the side wall of the housing 12 and in the vicinity of the position where the ultrasonic probe 30 is disposed (in the vicinity of the ultrasonic radiation surface). . The through hole 26 is a drain hole for removing water that has entered the periphery of the magnet 24. It has the effect of preventing the magnet 24 from rusting due to the stagnation of water.

Next, a submerged bolt inspection method using the above inspection jig 10 will be described with reference to FIG.
First, the casing 12 in which the ultrasonic probe 30 is installed in the first opening 14 is disposed at the protruding end of the underwater bolt 40 to be inspected. The housing 12 may be arranged by inserting an end from the second opening 16. The end of the bolt 40 inserted from the second opening 16 comes into contact with the ring-shaped member 22 disposed in the irrigation region 20, so that the insertion amount is determined.

  The end of the bolt 40 that contacts the ring-shaped member 22 is attracted to the ring-shaped member 22 side by a magnet. By this action, the housing 12 is semi-fixed with respect to the end of the bolt 40. When such an operation is performed underwater, when the casing 12 is semi-fixed to the end of the bolt 40, the irrigation region 20 inside the casing 12 is filled with water.

  In a state where the casing is semi-fixed to the end of the bolt 40 to be inspected with a predetermined insertion amount and the irrigation region 20 is filled with water, ultrasonic waves are emitted from the ultrasonic radiation surface of the ultrasonic probe 30. Radiate. The emitted ultrasonic wave propagates through the water filled in the irrigation region 20 and reaches the end face of the bolt 40. The ultrasonic wave that reaches the end face of the bolt 40 is divided into a reflected wave and an incident wave, and the incident wave propagates inside the bolt 40. If the bolt 40 has a scratch 42 or a crack, a part of the incident wave is reflected by a tomographic plane generated by the scratch 42 or the crack, and is reflected from the end of the bolt 40 toward the ultrasonic probe 30 as a reflected wave. Released.

  The reflected wave radiated from the end face of the bolt 40 is received by the ultrasonic probe 30, and by analyzing this characteristic, it is possible to determine the presence or absence of scratches 42 or cracks on the bolt 40.

Next, an example of an experimental result obtained by performing a flaw detection on the bolt 40 disposed in water using the inspection jig 10 having the above-described configuration will be described. In the incident,
Bolt diameter: φ = 24mm
Bolt length: L = 300mm
Distance from ultrasonic probe to bolt end face: l = 38mm
Bolt end face insertion amount: dl = 5mm
And then
Distance from ultrasonic incident end surface to scratch: Ls = 50 mm, 115 mm
Scratch depth: D = 24mm, 12mm, 6mm
About, the data at the time of ultrasonic emission were acquired.

  4 to 6 show reflected wave waveform data of a bolt 40 having a scratch at a position of Ls = 50 mm. 4 shows the experimental results when D = 24 mm, FIG. 5 shows the experimental results when D = 12 mm, and FIG. 6 shows the experimental results when D = 6 mm. In the waveform data shown in FIG. 4 to FIG. 6, the reflected wave S1 is a reflected wave at the bolt end face on the ultrasonic incident side, and the reflected wave S2 is reflected from the ultrasonic probe 30 by the reflected wave S1. It is a secondary reflected wave reflected from the bolt end face again. The reflected wave F generated between the reflected wave S 1 and the reflected wave S 2 is a reflected wave caused by the scratch 42 provided on the bolt 40. In order for the reflected wave F from the flaw in the bolt investigation range to be displayed between the reflected waves S1 and S2, the distance l between the ultrasonic probe 30 and the bolt end surface is l> L · Vw / Vm. There is a need. Here, L is the investigation range of the bolt, Vw is the ultrasonic velocity in water, and Vm is the ultrasonic velocity in the bolt.

  4 to 6, the reflected wave F is approximately generated at the position where the scratch 42 is provided, and when D = 6 mm, D = 24 mm, and D = 12 mm. It can be read that the reflected wave is small as compared with FIG.

  Next, FIGS. 7 to 9 show the reflected wave waveform data of the bolt 40 having a scratch at a position of Ls = 115 mm. 7 to 9, in FIG. 7, D = 24 mm, in FIG. 8, D = 12 mm, and in FIG. 9, D = 6 mm. Also in the experimental results shown in FIGS. 7 to 9, as in the examples shown in FIGS. 4 to 6, the reflected wave F indicating the presence of the scratch 42 is roughly generated at the position where the scratch 42 is provided. Can be read. Further, the difference between the depth of the scratch 42 and the magnitude of the reflected wave is significantly different from the case of Ls = 50 mm. That is, as the flaw depth D becomes shallower, the reflected wave F becomes smaller.

  From such an experimental result, it can be understood that the reflected wave F that appears due to the presence of the scratch 42 can roughly determine the position where the scratch 42 exists. Further, it can be understood that the magnitude of the reflected wave F is inversely proportional to the distance from the end face on which the ultrasonic wave is incident, and proportional to the depth (size) of the scratch 42.

Therefore, when the inspection jig 10 having the above-described configuration is used, as shown in FIG. 10, the apparatus body 32 of the ultrasonic inspection apparatus 28 is arranged on the ship 50 and a measurement person (not shown) performs measurement. A diver (not shown) working in water can make a continuous inspection by operating the inspection jig 10 provided with the ultrasonic probe 30 while making the determination. In other words, if the measurer and the diver can communicate with each other, it is possible to continue the inspection without having to rise to the surface of the diver by simply contacting the measurement completion, re-measurement, during measurement, etc. It is.
For this reason, for example, the apparatus main body 32 may be provided with a monitor and a transmission / reception microphone (not shown) so that the video of the camera 34 carried by the diver and the sound of the microphone (not shown) can be acquired. This is because, by adopting such a configuration, it is possible to easily communicate between the measurer and the diver, such as the end of measurement, re-measurement, and during measurement.

  In addition, the housing 12 can be easily attached to and detached from the end of the bolt 40 during work, and the housing 12 is semi-fixed during mounting, enabling efficient and highly accurate measurement. It becomes.

  In the above embodiment, the casing 12 is shown as a combination of cylindrical bodies having different diameters. However, the appearance may be a simple cylindrical body, not a cylinder. A square tube may be used.

  Moreover, in the said embodiment, the inspection jig 10 demonstrated that the housing | casing 12 was set in the state which made the axis line parallel with respect to the volt | bolt 40 made into a test object. However, the flaw detection inspection is performed by arranging the ultrasonic radiation surface of the ultrasonic probe 30 so as to be inclined with respect to the end face of the bolt 40 (with an inclination angle θ with respect to the perpendicular L having the end face as a base point). As a result, the ultrasonic wave radiated from the ultrasonic probe 30 is reflected by the side surface of the bolt 40 and received. As a result, it is possible to efficiently detect corrosion 44 or scratches generated on the side surface of the bolt 40.

  For this reason, the inspection jig 10 according to the present invention may be configured to include an adjustment member 36 as shown in FIG. 11 on the second opening 16 side. The adjustment member 36 is provided with a vertical opening 36a for inserting the bolt 40 on the surface facing the bolt 40, and for tilting the housing 12 on the surface facing the second opening 16. What is necessary is just to set it as the structure provided with the inclined surface 36b and the insertion part 36c for inserting in the 2nd opening part 16. FIG. The adjustment member 36 is provided with a through hole 36d extending on an extension line of the irrigation region 20 provided in the casing pair 12.

  By arranging the adjustment member 36 having such a configuration, the ultrasonic wave radiated from the ultrasonic probe 30 is incident on the end face of the bolt 40 with an inclination angle θ. As a result, the ultrasonic waves reach and reflect the side surface of the bolt 40, and the corrosion 44 and the like generated on the side surface of the bolt 40 can be effectively detected.

  Further, the incident position (direction) of the ultrasonic wave radiated from the ultrasonic probe 30 can be changed by rotating the casing 12 together with the adjustment member with the bolt 40 as a base point. Therefore, it is possible to apply ultrasonic waves to the entire circumference of the side surface of the bolt 40.

  In the example shown in FIG. 11, the adjustment member 36 is interposed in order to fix the housing pair 12 to the bolt 40 in a tilted state. However, when the inspection jig 10 according to the embodiment is dedicated to the side surface inspection of the bolt 40, the shape of the second opening 16 itself may be changed as shown in FIG. In such a configuration, the ultrasonic probe 30 is disposed with an inclination angle θ with respect to the perpendicular L along the axis of the bolt 40 simply by assembling the inspection jig 10 to the bolt 40. Because it will be.

10 ......... Inspection jig, 12 ......... Case, 14 ......... First opening, 16 ......... Second opening, 18 ......... Holder, 20 ......... Watering area, 22 ......... Ring 24 ......... Magnet, 26 ......... Through hole, 28 ...... Ultrasonic inspection device, 30 ...... Ultrasonic probe, 32 ......... Main body, 34 ...... Camera, 36 ... ...... Adjusting member, 36a ......... Vertical opening, 36b ......... Inclined surface, 36c ......... Insertion part, 36d ......... Through hole, 40 ......... Bolt, 42 ......... Scratch, 44 ......... Corrosion, 50 ... ship.

Claims (7)

A first opening for placing an ultrasonic probe;
A second opening that is provided in communication with the first opening on a straight line of the first opening and that inserts an end of a bolt installed in water;
An irrigation region is provided between the ultrasonic probe disposed in the first opening and the bolt inserted in the second opening,
An underwater bolt inspection jig, wherein a ring-shaped member made of a non-magnetic member is disposed in the irrigation region, and the amount of insertion of the bolt is adjusted.   The underwater bolt inspection jig according to claim 1, wherein a magnet that is attracted to the bolt end portion is disposed in the irrigation region on the second opening side.   The underwater bolt inspection jig according to claim 1 or 2, wherein an angle adjusting member for adjusting an insertion angle of the casing with respect to the bolt end portion is provided on the second opening side of the casing.   The underwater bolt inspection jig according to claim 1 or 2, wherein the second opening is configured to be inserted in a state where the casing is inclined with respect to the bolt. A jig equipped with an ultrasonic probe is placed on the end of a bolt installed in water, and the end of the bolt on which the jig is placed is attracted to the jig by a magnetic force at a predetermined insertion position. An underwater bolt inspection method for detecting flaws of the bolt by outputting ultrasonic waves from the ultrasonic probe in a state where water is interposed between an end of the bolt and the ultrasonic probe. ,
An underwater bolt inspection method , wherein a ring-shaped member made of a non-magnetic member is disposed in the irrigation region of the jig, and the insertion amount of the bolt is adjusted .   6. The flaw detection of the bolt is performed by arranging the ultrasonic radiation surface of the ultrasonic probe so as to have an inclination angle with respect to a perpendicular line having an end portion of the bolt as a base point. The underwater bolt inspection method described in 1.   The underwater bolt inspection method according to claim 5 or 6, wherein flaw detection of the bolt is performed while communicating between a measurement person on the water and an underwater diver via a communication means.

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