Ultrasonic Prove System For Flaw-detection Of Material

Abstract

An ultrasonic flaw-detecting system comprising a storing chamber for liquid formed between a shoe and cover therefor, a flaw-detecting opening and a precooling passage provided through said cover and said shoe, the shoe-side face of said precooling passage having a sawtooth configuration, an ultrasonic flaw-detecting device positioned in said flaw-detecting opening, and inlets for supplying liquid mounted through said cover.

Description

The present invention relates in general to ultrasonic flaw-detecting systems for the internal defect detection of material and more particularly to a sliding block for ultrasonic flaw-detection at high temperature.

A shoe-coupling system is already known as a sliding block for ultrasonic flaw detection. In such a case, it is well known that many troubles arise in the flaw detection of material having an elevated temperature.

Bubbles which are generated as a consequence of the boiling of the liquid, which is the contacting medium for ultrasonic coupling, on the surface of materials having high temperatures is one of said troubles. Such bubbles become a big hindrance to ultrasonic transmission. Accordingly, some precooling devices are commonly adopted, for example, a cooling water wheel and spray system or a cooling plate, or the like. This precooling temperature should be maintained below some critical surface temperature for ultrasonic coupling, which is 125.degree. C. in the case of a liquid. It is well known that oily dusts and mill scales are apt to stain the surface of hot-rolled materials. It is needless to say that the presence of these dusts and scales have a hydrophobic action. For this reason, large amounts of water sprinkling are called for in the front of said ultrasonic-detecting system. It is, however, difficult to prevent the temperature restoration of said materials after said water sprinkling. Consequently, it is unavoidable that the ultrasonic flaw-detecting process becomes unstable.

The present system has been developed in order to eliminate the above-mentioned troubles. For this purpose the ultrasonic flaw-detecting device and a shoe having a concave-convex bottom surface are combined as a unit-sliding block.

An object of this invention is to provide an ultrasonic flaw-detecting system which can check the generation of bubbles.

Another object of this invention is to provide an ultrasonic flaw-detecting system which avoids the phenomenon of temperature restoration.

Other objects and advantages will become apparent from the following detailed descriptions and the accompanying drawing in which:

The FIGURE is a diagrammatic elevation of the ultrasonic flaw-detecting system in accordance with the principles of this invention.

Referring now to the accompanying drawing, the ultrasonic flaw-detecting device 8 is positioned at a flaw-detecting opening 2 provided through the central part of a shoe 1 and cover 11 of said shoe 1. The inlet nozzle 4 for cooling water is attached at the front of said cover 11 and another inlet nozzle 3 for contacting water is attached at the rear of said cover 11. Said inlet nozzle 4 for cooling water is in communication with a cooling passage 7, which is formed between the sawtooth-like concave-convex bottom surface 7a at the front of shoe 1 and the material 9 to be inspected and a water-storing chamber 5 formed between said shoe 1 and said cover 11, through nozzle portion 6. Said inlet nozzle 3 for contacting water is in communication with said flaw-detecting opening 2 through another water-storing chamber 15 which is formed between the rear of shoe 1 and said cover 11. The above-mentioned inlet nozzles 3 and 4 can be a single inlet unit without separation as in the drawing.

It is needless to say that said shoe 1 can be slid on said material 9.

The cooling water injected from said inlet nozzle 4 to storing chamber 5 is jetted to cooling passage 7 which has a clearance formed between said shoe 1 and the material 9, through said nozzle portion 6. In such case, said cooling water becomes a turbulent flow in said hole 7 because of the accelerated velocity created by said nozzle portion 6. Said sawtooth face 7a is very effective in making the formation of the turbulent flow easy and stable. That is, the flow velocity of said cooling water will change in a large way depending upon said sawtooth face. Said velocity becomes large forward of each convex angle and then becomes small forward of each concave angle. In such a process, an eddy current is formed. When such an action is repeated, violent turbulent flow is formed and gives said cooling water a large agitating action. The effects of such a cooling system is far more excellent than that in prior arts. It is needless to say that no bubbles are generated.

In this invention, while precooling means and flaw-detecting means are jointed as a unit, the phenomenon of temperature restoration does not occur.

Claims

What we claim is:

1. An ultrasonic-testing system for the flaw-detection of material comprising a shoe capable of being slid on the material to be inspected, a flaw-detecting device, a cover for said shoe having a storing chamber for liquid provided between said shoe and said cover, an inlet nozzle for liquid attached to said cover and being in communication with said storing chamber, said shoe and cover having a flaw-detecting opening with said flaw-detecting device positioned in said opening, said shoe having a recessed sawtooth face provided in one end portion of said shoe whereby when said shoe is on the material being tested said recessed face is spaced from said material and provides a precooling passage between said shoe and said material to be inspected, and said shoe having a nozzle portion provided between and connecting said storing chamber and said recessed sawtooth face.