JPH0524053Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a local water immersion ultrasonic flaw detection device in which a probe is locally immersed in water.

(B) Prior Art Conventional local water immersion ultrasonic flaw detection equipment uses a large number of ultrasonic probe heads using shoes in manufacturing lines for steel plates, pipes, billets, etc. 1
The number of probe heads per line is about 1 to 300. One to eight probes are incorporated into one flaw detection head.

The probe head performs flaw detection while sliding over the material to be inspected. At this time, water is used to float the probe head or water for flaw detection.
This water supply method can be roughly divided into a dynamic pressure levitation method and a static pressure levitation method.

A typical example of a hydrodynamic levitation probe head is shown in Part 3.
As shown in FIG. Figure 3 is a longitudinal sectional view of the probe head, and Figure 4 is a -
It is a bottom view seen from a line.

A shoe 2 is attached to the bottom surface 11 of the probe head 1, and a floating water puddle recess 111 and a flaw detection water puddle recess 112 are provided. There are multiple probes 3 (four in the example shown) in the center of the head.
is attached, and the probe part 31 of the probe 3 is placed in the recess 1.
It protrudes within 12.

The concave portion 112 is connected to the water conduit 4, and water for flaw detection is supplied thereto. A drainage hole 12 is communicated with the recess 112 to discharge water and air accumulated in the recess 112.

The concave portion 111 is connected to the water conduit 5, and water for flotation is supplied thereto.

In a hydrodynamic levitation type probe head having such a structure, high-pressure water is ejected from the bottom of the head on the upstream side to form a water film between the head and the material to be inspected 8, causing the head to float. Flaw detection is performed by supplying water for flaw detection into a recess 112 provided at the bottom of the head.

In such heads, the levitation effect appears only when the head and the material to be inspected are moving at a fairly high relative velocity (1 m/s or more). At low speeds, no floating effect can be obtained and shoe wear cannot be prevented. Further, the direction of relative movement is limited to one direction, and the desired effect cannot be obtained when moving in other directions.

Typical examples of hydrostatic levitation type probe heads are shown in FIGS. 5 and 3. FIG. 5 is a longitudinal sectional view of the probe head, and FIG. 6 is a bottom view taken from the - line in FIG.

Reference numbers in FIGS. 5 and 6 that are the same as those in FIGS. 3 and 4 indicate the same parts or parts. In this type of head, floating water pool recesses 111 are provided on the upstream and downstream sides with a flaw detection water pool recess 112 in between. The rest of the structure is the same as the hydrodynamic levitation head described above.

The disadvantages of this type of head are that it is large in size, the undetected area at the end of the material being inspected becomes large, and when a large number of heads are used side by side, the entire head occupies a large area. There is.

As another method, there is a header having a structure in which the floating water reservoir recess and the flaw detection water reservoir recess are connected through a small hole, and the header serves both as floating water and flaw detection water (Japanese Patent Application Laid-Open No. 54-33089). However, this header is no different from the hydrostatic levitation type header in terms of size.

Some headers for flaw detection on curved surfaces of materials to be inspected are equipped with wheels and have a structure in which water for flaw detection is ejected from around the probe. (Japanese Unexamined Patent Publication No. 1983-68665). However, this wheel-type structure does not allow smooth movement in all directions, so it is not suitable for full-surface inspection.

(c) Problems to be solved by the invention The problem to be solved by the invention is to create a head that can reduce the overall size and expand the flaw detection range by using both flotation water and flaw detection water. The object of the present invention is to obtain a local water immersion ultrasonic flaw detection device having the following characteristics.

(d) Means for solving the problem In the local water immersion ultrasonic flaw detection device of the present invention, each probe is arranged symmetrically with respect to the center point of the bottom surface of the head that holds the probe, and A mutually independent recess is formed surrounding the lower part of the probe, a water supply hole and a drainage hole are provided in communication with the recess, a water supply system is connected to the water supply hole, and water for flotation and flaw detection is supplied to the recess. The above problem is solved by the supply means.

Water and air stagnant in the recess are guided to the outside of the head through the drainage hole, and a nozzle connected to the drainage hole is used to blow a drainage airflow onto the top of the probe. is preferred.

Note that the probes are preferably arranged in a staggered manner at regular intervals in the flaw detection scanning direction so as not to overlap.

(E) Embodiment An embodiment of the local water immersion ultrasonic flaw detection device of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a longitudinal sectional view of a probe head used in this apparatus, and FIG. 2A is a bottom view taken from the - line in FIG. 1. FIG. 2B shows a modified example.

Each probe 3 is arranged symmetrically with respect to the center point O of the bottom surface 11 of the head 1 that holds the probe 3. Recesses 113, which are independent from each other, are formed on the bottom surface of the head 1 so as to surround the lower part of each probe 3. Recessed portion 113
A water supply hole 61 and a drainage hole 71 are provided which communicate with each other. A water supply system is connected to the water supply hole 61 through the water conduit 6, and water for flotation and flaw detection is supplied to the recess 113.

The water and air remaining in the recess 113 are guided to the outside of the head 1 through the drainage hole 71, and are passed through the nozzle 7 connected to the drainage hole 71 to the probe 3.
Blow a drainage air stream over the top. In this way, it performs the function of cooling the probe at the same time as the function of drainage air.

Reference numbers in FIGS. 1 and 2 that are the same as those in FIGS. 3 to 6 are as follows:
Denote the same part or part. Therefore, further explanation of the same items will be omitted.

The recesses 113 may be arranged uniformly around the center point O on the bottom surface 11 of the head 1 as shown in FIG. It may be placed in a specific location. In either case, the recess 113 may be arranged so that the head floats evenly above the surface of the material to be inspected.

The pressure of the water for flotation and flaw detection is preferably 1 to 5 kg/cm ² . For example, the flying height of the head above the steel plate is approximately 0.15 mm. As a result, running resistance becomes almost zero regardless of the scanning direction of the head. In addition, even if there is a bend of about 5 mm per 1 m,
Levitation is well maintained.

Since the recesses 113 are provided independently from each other,
Even if the head tilts to one side, pressure fluctuations do not spread to the entire head, and the tilt can be restored quickly.

(F) Effects According to the present invention, a larger number of probe heads can be arranged in the same space than before, and flaw detection efficiency can be increased.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a probe head used in the local water immersion ultrasonic flaw detection device of the present invention. FIG. 2 is a bottom view taken from the - line in FIG. 1, and FIG. B shows a modified example. FIG. 3 is a longitudinal sectional view of a conventional probe head.
FIG. 4 is a bottom view taken from the - line in FIG. 3. Fifth
The figure is a longitudinal sectional view of another conventional probe head. FIG. 6 is a bottom view taken from the - line in FIG. 5. DESCRIPTION OF SYMBOLS 1...Probe head, 2...Show, 3...Probe, 4...Water pipe, 5...Water pipe, 6...Water pipe, 7...Nozzle, 11...Bottom surface, 12... ...Drainage hole, 111...Water pool recess for floating, 112...
Water puddle recess for flaw detection, 113... recess.

Claims (1)

[Claims for Utility Model Registration] 1. Each probe is arranged symmetrically with respect to the center point of the bottom surface of a head that holds the probes, and there are mutually independent recesses on the bottom surface of the head surrounding the lower part of each probe. a water supply hole and a drainage hole communicating with the recess, a water supply system is connected to the water supply hole, and water for flotation and flaw detection is supplied to the recess. Device. 2. The water and air remaining in the recess are guided to the outside of the head through the drainage hole, and a nozzle connected to the drainage hole is used to blow a drainage airflow onto the top of the probe. 2. A device according to claim 1, characterized in that: