JPS6259777B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a contact tracking device for an ultrasonic flaw detector that inspects surface flaws on steel pieces. In general, there are visual methods, magnetic particle detection methods, ultrasonic flaw detection methods, etc. to inspect surface flaws on steel slabs, but the ultrasonic flaw detection method described above has the advantage of being able to automate the inspection and having better flaw detection performance than other methods. Because of this, it has recently become widely adopted. However, in order to obtain good flaw detection performance, at least the following three conditions must be satisfied. Firstly, it is necessary to stably generate a surface wave on a twisted steel piece (hereinafter referred to as a steel piece).
As shown in Figure 1b, the angle α between the vertical center line (line 1) of the probe and the surface of the steel piece must be less than ±1°; Displacement l between the vertical center line (line 1) and the center line of the steel piece (line 2)
If it is not ±2 mm or less, it will not be possible to improve the accuracy of determining the location of flaws on a bent steel billet, and third, as shown in Figure 1c, Unless the angle β formed by the longitudinal center lines (three lines) is ±1° or less, the reception efficiency of surface waves from a warped steel piece will not increase. Good flaw detection performance by ultrasonic flaw detection can be obtained by satisfying the above-mentioned conditions. Conventionally, tracking devices have been provided that allow contacts to follow the twisting and bending of steel pieces.
It has been difficult to take full advantage of the characteristics of ultrasonic flaw detection, which has a complex structure and poor flaw detection performance. SUMMARY OF THE INVENTION An object of the present invention is to propose a device that can freely and easily follow the twisting and bending of a steel billet, and to contribute to improving the detection performance of flaws in a steel billet. DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of a contact tracking device according to the present invention will be explained below with reference to the drawings. As shown in FIGS. 2a, b, and 3 (view of arrows A to A in FIG. 2b), two guide rollers 1 and a frame are provided with flanges that loosely fit on opposite sides of a square steel piece 30. A mounting seat 5 is installed on the short side of the rubber tire 2 and is equipped with an adjustment screw 3 and a pin 4 for positioning the rubber tire 2.
an inner frame 6 on which a rubber tire 2 with a built-in contactor is mounted; A sliding shaft 9 with an alignment spring 8 loosely inserted is provided in the center of the frame to allow the inner frame to rotate, and a sliding shaft 9 into which an alignment spring 8 is loosely inserted is provided to prevent the inner frame from rotating. As shown in FIG.
Arm sliding bearings 11 into which a sliding shaft 9 protruding from the top is loosely inserted are fixed at both ends, and an outer frame brake holds an outer frame holding core rod and an outer frame holding spring in order to suppress rotation of the outer frame 10. A curved arm 12 equipped with a seat, and furthermore,
A protruding plate 13 is provided at the lower part of the curved arm 12, and the plate 13 is fixed to an underframe 14 as shown in FIG. 4 (view of arrows B to B in FIG. 2b). The curved arm 12 is held from both sides by an arm presser core rod 17 that is loosely inserted into the arm brake seat 15 and holds a roller 16 at its tip, and an arm return spring 18 that is loosely inserted into the arm presser core rod 17.
It is braking the rotation. Furthermore, as shown in FIG. 2b, it is loosely inserted into an underframe sliding bearing 19 fixed to the underframe 14, a retaining ring 20 is attached to one end, and the other end is connected to an air cylinder 22 via a connecting arm 21. A hollow outer shaft 25 whose end has a flange 24 that presses the inner shaft spring 23, and a stopper which is loosely inserted into an internal sliding bearing 26 inscribed in the hollow outer shaft 25 and tightened with a nut 27 at one end. 2
8, and the other end consists of an inner shaft 29 into which the above-mentioned inner shaft spring 23 is loosely inserted, which is fixed to the curved arm 12 and is latched by a retaining ring 20 of a hollow outer shaft 25. . Next, the operating state of the follow-up device of the present invention will be explained with reference to the drawings. When a limit switch or the like (not shown) detects that the tip of the diamond-shaped square steel piece conveyed by the drum-shaped roller table has passed through this device, a pair of When the air cylinder 22 operates, the hollow outer shaft 25 connected via the connecting arm 21 slides on the underframe sliding bearing 19. The hollow outer shaft 25 has an inner shaft 29 connected to the hollow outer shaft 2.
5 and the retaining ring 28 of the inner shaft 29, so when the hollow outer shaft 25 moves to one side of the steel, the inner shaft 2 to which the curved arm 12 is fixed
9 also moves due to its own weight, and the curved arm 12 holds the outer frame 10 which supports the inner frame 6 on which the guide roller 1 and the rubber tires 5 are mounted via the rotary bearing 7. As the inner side 29 moves, the guide roller 1 and rubber tire 2 move to clamp the steel piece 30. If the steel piece 30 is bent upward to the left as shown by the dotted line in FIG. 5 and is further twisted, the outer frame 10
As the sliding shaft 9 protruding from the curved arm 12 slides on the sliding bearings 11 at both ends of the curved arm 12 and moves to the left,
In the upward direction, the inner shaft 29 fixed to the curved arm 12 slides into the hollow outer shaft 25 and is pushed upward, and in the torsion, the inner frame 6, which is pivotally supported by the rotation bearing 7 of the outer frame 10, tilts. and follow. Next, when the steel piece 30 is no longer bent or twisted, the outer frame 10 and the curved arm 12, which had been pushed upward, are pushed down by the inner shaft spring 23, which has been loosely inserted into the inner shaft 29 and compressed. The outer frame 10, which had moved to the left, is pushed to the right by the compressed centering spring 8, which is loosely inserted into the sliding shaft 9, and returns to its original position.The twist is caused by the rotation of the outer frame 10. Bearing 7
The inner frame 6, which was pivotally supported by the inner frame 6, returns to its original position. Furthermore, if the steel piece is warped, the bending arm 12 rotates around the inner shaft 29 to follow the curve, but when the warp disappears, the arm brake seat 15 attached to the underframe 14 moves as shown in FIG. Roller 1 is attached to the tip
The arm presser core rod 17 holding the curved arm 6 and the arm return spring 18 return by pushing back the plate 13 fixed to the lower part of the curved arm 12. Next, Table 1 shows the flaw detection rate (%) by the magnetic particle flaw detection method and the ultrasonic flaw detection method using the apparatus of the present invention.

[Table] As shown above, the reason why the detection rate of ultrasonic flaw detection is much better than that of magnetic particle flaw detection is that ultrasonic flaw detection originally has superior flaw detection ability, but the present invention's This is largely due to the quality of the equipment. As described above, the tracking device of the present invention is an excellent device that can freely and easily follow even complex deformations of steel slabs, making the ultrasonic flaw detection method effective. Further, the follow-up device of the present invention may be installed within the billet transfer line, or the device may be mounted on a trolley so that it can be evacuated from the billet transfer line for easy repair and inspection. .

[Brief explanation of the drawing]

FIG. 1 is a drawing showing the state of deformation of a steel piece. FIG. 2a is a plan view of the device, with the upper half showing a cross section.
FIG. 3 shows the view from A to A in FIG. 2b. FIG. 4 shows the view from arrow B to B in FIG. 2b. FIG. 5 shows how the device follows the deformation of the steel piece. 1...Guide roller, 2...Rubber tire with built-in probe, 3...Adjustment screw, 4...Pin, 5
...Mounting seat, 6...Inner frame, 7...Rotating bearing, 8...
...Alignment spring, 9...Sliding shaft, 10...Outer frame, 11
... Arm sliding bearing, 12 ... Curved arm, 13
... Plate, 14 ... Underframe, 15 ... Arm brake seat, 16 ... Roller, 17 ... Arm presser core, 18 ... Arm return spring, 19 ... Underframe sliding bearing, 20 ... Retaining ring , 21... articulating arm, 2
2...Air cylinder, 23...Inner shaft spring, 2
4...flange, 25...hollow outer shaft, 26...internal sliding bearing, 27...nut, 28...stopper,
29...Inner shaft, 30...Square steel piece.

Claims (1)

[Claims] 1. An inner frame that supports guide rollers that hold the object to be inspected facing each other and a tire that has a built-in probe and runs on the surface of the object to be inspected, an outer frame that pivotally supports this inner frame in a tiltable manner, and this outer frame. a curved arm that is slidably held via a sliding bearing and a spring, and an inner shaft that has one end connected to the center of the curved arm, and the curved arm has an arm brake fixed to the underframe. It is held between the return spring of the seat and the core rod, and
A probe tracking device characterized in that the inner shaft is loosely inserted into a sliding bearing fixed to the underframe and inserted into a hollow outer shaft operated by a cylinder.