JPH03255347A - Underwater inspection apparatus - Google Patents

Abstract

PURPOSE:To detect the defect in the surface of a body under inspection with monitoring camera readily by penetrating penetrant which is jetted from a penetrant jetting means into a defective part when there is the defect such as a crack in the surface of the body under inspection, and projecting ultraviolet rays into the defective part. CONSTITUTION:A chamber 1 whose lower side is opened is lowered on a body under inspection 4 with wire ropes 3. Water in the chamber 1 is drained with a water draining pad 10. The inside of a vacuum pad 5 is made to be the vacuum state with a vacuum pump 7 and brought close contact with the body under test 4. Drying air is blown on the body under test 4 from a jetting nozzle 22 so as to dry the surface. Then, fluorescent penetrant is atomized. Thereafter, ultraviolet rays are projected on the body under test 4 from a black light 29. Then the penetrant which is permeated into a defect 30 in the surface emits fluorescence. Therefore, the defect 30 in the surface of the body under test 4 can be readily detected with a monitoring camera 28.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention uses penetrant testing, which is one of the non-destructive testing methods, to inspect defects occurring in underwater structures. This relates to underwater inspection equipment.

(Prior Art) Conventionally, methods for inspecting defects occurring in underwater structures (for example, offshore structures, internal structures of nuclear reactors, etc.) include:
For example, there are methods of visually inspecting the surface of a structure using an optical device such as a periscope, fiberscope, or borescope, and methods of inspecting for defects using radiation such as X-rays. However, the former method has the problem that when the type of defect is a crack, it is difficult to distinguish it from a scratch caused by a grinder or the like, and furthermore, it is difficult to distinguish whether the depth of the crack is shallow or deep. Furthermore, in the latter method, since the film must be placed on the other side through which the X-rays pass, there is a problem in that it is not possible to carry out inspections using X-ray photography in locations where it is difficult to install the film.

(Problem to be Solved by the Invention) On the other hand, in addition to the above-mentioned method, there is a penetrant test that can easily identify cracks that occur in welded parts. Since it is a method of coating and inspecting welds for cracks, etc., there was a problem that it could not be carried out underwater.

The present invention was made in view of the above-mentioned problems, and provides an underwater FI inspection device that can easily detect defects such as cracks that occur in underwater structures using penetrant testing. The purpose is to provide.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention provides a chamber with an opening at the bottom, a lifting means for suspending the chamber above the object to be inspected below the water surface, and A vacuum pad provided at the opening edge of the chamber, a vacuum evacuation means connected to the vacuum pad, a drainage means for discharging water that has entered the chamber to the outside, and a water discharge means that discharges water that has entered the chamber to the outside. The apparatus is equipped with a penetrating liquid ejecting means for ejecting a liquid, an ultraviolet irradiation means for emitting ultraviolet rays onto the object to be inspected in the chamber, and a monitor camera for penetrant testing provided in the chamber.

(Function) According to the above configuration, when there is a defect such as a crack on the surface of the object to be inspected, the penetrating liquid ejected from the penetrating liquid spouting means penetrates into the defective part, so that the ultraviolet irradiation means can remove the surface of the object to be inspected from the ultraviolet irradiation means. By irradiating the surface with ultraviolet rays, defects such as cracks that occur on the surface of the object to be inspected can be easily detected with a monitor camera.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a longitudinal sectional view of an underwater inspection apparatus showing an embodiment of the present invention, in which a plurality of hooks 2 are provided at the upper part of a chamber 1. Wire lobes 3 are connected to each of these hooks 2, and the wire lobes 3 are unwound from a winding drum by a wire lobe winder (not shown) serving as a lifting means, and the chamber 1 is moved to a test object 4 under water.
It is configured to be suspended from above.

Further, the chamber 1 is open at the bottom, and a vacuum pad 5 made of an elastic material is provided at the edge of the opening. A vacuum pump 7 as evacuation means is connected to the vacuum pad 5 via an exhaust pipe 6, and the suction force of the vacuum pump 7 maintains the inside of the vacuum pad 5 in a vacuum.

The inside of the chamber 1 is partitioned into a lower space 9A and an upper space 9B by a partition plate 8, and a drainage pad 10 as a drainage means is provided in the lower space 9A. A drain pipe 11 connected to a drain pump (not shown) is connected to this drain pad IO, and is configured to drain water in the lower space 9A to the outside through this drain pipe 11.

Note that the partition plate 8 is provided with a pressure sensor 12 for detecting the pressure in the lower space 9A, and
An exhaust pipe 13 and a safety valve 14 are provided to exhaust air in A, and the exhaust pipe 13 is provided with a check valve (not shown).

In the center of the lower space 9A, a rotating body 1 having a cylindrical shape is provided.
5 is provided. This rotary body 15 is rotatably supported by the partition plate 8 via a bearing 16, and the upper space 9B
It is designed to be rotationally driven by a rotating body drive mechanism 17 provided in the. The rotating body drive mechanism 17 is composed of a motor 18, a gear mechanism 19 that transmits the rotational force of the motor 18 to the rotating body 15, and a position detector 20 that detects the rotational position of the rotating body 15.

The lower part of the rotating body 15 is hermetically closed by a transparent plate 21, and a jet nozzle 22 is provided on the lower surface of the transparent plate 21 with the nozzle opening facing downward.

This jet nozzle 22 has a switching valve 2 as shown in FIG.
A penetrant supply pipe 24, a cleaning water supply pipe 25, a drying air supply pipe 26, and a developer supply pipe 27 are connected through 3a, 23b, 23c, and 23d, and the washable fluorescent penetrant is supplied from these supply pipes. , cleaning water, drying air (warm air)
and developer are supplied.

On the other hand, a monitor camera 28 for inspection is provided inside the rotating body 9, and a black light 29 is also provided as an ultraviolet irradiation means.
The object to be inspected 4 is irradiated with ultraviolet rays from the ultraviolet rays, and defects 30 occurring in the object to be inspected 4 are detected by a monitor camera 28. Furthermore, in addition to the inspection monitor camera 28 and the black light 29, a position detection monitor camera 31 and an illumination light 32 are provided inside the rotating body 15. Note that a transparent plate cleaning spray nozzle 33 for cleaning the transparent plate 18 is provided in the lower space 9A. Further, in FIG. 1, numeral 34 is an underwater lighting device, and numeral 35 is an underwater monitor camera.

Next, when performing a penetrant test on the object 4 to be inspected under water using the underwater inspection apparatus configured as described above, first, the wire lobe 3 is unwound from the winding drum by a wire lobe winder (not shown), and the chamber 1 is attached to the object to be inspected. 4. Descend above. Next, drain the water in chamber 1 from drain pipe 1 through drain pad lO.
At the same time, the vacuum pump 7 is driven to discharge the water in the vacuum pad 5 to the outside. In this way, the water inside the vacuum pad 5 is discharged to the outside by the vacuum pump 7, and when the inside of the vacuum pad 5 becomes a vacuum state, the vacuum pad 5 comes into close contact with the surface of the test object 4, causing water to flow into the chamber 1. Water intrusion is prevented.

Next, after confirming with the monitor camera 28 that the water in the chamber 1 has been completely drained to the outside by the drainage pad 10,
While illuminating the surface of the object to be inspected 4 with the illumination light 32 , the surface of the object to be inspected 4 is observed with the monitor camera 28 , and if there is limescale or dirt attached to the surface of the object to be inspected 40 , air is ejected from the jet nozzle 22 . Washing water is jetted out to remove limescale, dirt, etc. adhering to the surface of the object 4 to be inspected. Thereafter, the cleaning water spouted from the jet nozzle 22 is suctioned and removed by the drainage pad 10, and drying air is further blown onto the surface of the test object 4 from the jet nozzle 22 to dry the surface of the test object 4.

Note that if the pressure in the lower space 9A increases due to the drying air from the jet nozzle 22 at this time, the chamber 1
rises from the object to be inspected 4, so the lower space 9
The air in A is exhausted from an exhaust pipe 13 to prevent the chamber 1 from floating up.

Further, after the surface of the object 4 to be inspected is dried with the drying air, the washable fluorescent penetrating liquid is ejected from the jet nozzle 22 toward the object 4 to be inspected. Next, after a predetermined period of time has elapsed, cleaning water is jetted out from the jet nozzle 22 to wash and remove excess penetrating liquid on the object 4 to be inspected, and after drying the surface of the object 4 to be inspected, the jet nozzle 22 A developer is sprayed onto the surface of the object 4 to be inspected. Then, the surface of the object to be inspected 4 is irradiated with ultraviolet rays from the black light 29, and the surface of the object to be inspected 4 is observed by the monitor camera . At this time, the object to be inspected 4
If there is a defect 30 such as a crack on the surface of the object to be inspected 4, the fluorescent penetrating liquid penetrates into the defect and emits fluorescence due to the ultraviolet rays from the black light 29. It can be easily detected by the monitor camera 28.

In the above embodiment, a developer for fluorescent penetrant testing was sprayed onto the surface of the object to be inspected 4 to detect defects 30 such as cracks on the surface of the object to be inspected. Defects can be detected even if coating is omitted. In addition, although the explanation was omitted in the above embodiment, a mark 36 for position confirmation is placed in the center of the object to be inspected 4 as shown in FIGS. If attached, the object to be inspected 4
The position of can be easily detected by the monitor camera 31. Furthermore, when the surface of the object to be inspected 4 is concave or convex, it is difficult for the vacuum pad 5 shown in FIG. 1 to come into close contact with the surface of the object to be inspected 4, so that A lower chamber adapter 39 having a vacuum pad 37 and a curved seal drain port 38 is required as shown in FIG.

[Effects of the Invention] As explained above, the present invention provides a chamber with an opening at the bottom, a lifting means for suspending the chamber above the object to be inspected below the water surface, and a vacuum pad provided at the edge of the opening of the chamber. and a vacuum evacuation means connected to this vacuum pad,
A drainage means for discharging water that has entered the chamber to the outside, a penetrating liquid jetting means for spouting a penetrating liquid onto the object to be inspected in the chamber, and an ultraviolet irradiation means for irradiating the object to be inspected in the chamber with ultraviolet rays. and a monitor camera for penetrant testing provided in the chamber.

Therefore, it is possible to provide an underwater inspection device that can easily detect defects such as cracks occurring in structures under water using penetrant testing.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of an underwater inspection device showing an embodiment of the present invention, Fig. 2 is a diagram showing a piping system connected to the jet nozzle of the same device, Figs. 3(b) and 4(b) are side views of the inspected object, and FIGS. 5(a) and 5(b) show other embodiments of the present invention. FIG. DESCRIPTION OF SYMBOLS 1... Chamber, 2... Hook, 3... Wire robe, 4... Test object, 5... Vacuum pad, 7...
- Vacuum pump, 8... Partition plate, IO... Drainage pad, 15... Rotating body, 17... Rotating body drive mechanism, 22
...Blowout nozzle, 24...Permeate supply pipe, 25...
・Washing water supply pipe, 26...Drying air supply pipe, 27.
・Developer supply pipe, 28. 31 ・Monitor camera, 2
9...Black light.

Claims (1)

[Claims] a chamber with an open bottom, a lifting means for suspending the chamber above the object to be inspected below the water surface, a vacuum pad provided at the edge of the opening of the chamber, and a vacuum evacuation means connected to the vacuum pad; A drainage means for discharging water that has entered the chamber to the outside, a penetrating liquid jetting means for spouting a penetrating liquid onto the object to be inspected in the chamber, and an ultraviolet irradiation means for irradiating the object to be inspected in the chamber with ultraviolet rays. and a penetrant test monitor camera provided in the chamber.