KR20030033483A - multi-scanning ultrasonic inspector for weld zone - Google Patents

Abstract

PURPOSE: An ultrasonic wave multi-scanning probing device is provided to individually display ultrasonic wave signals through an ultrasonic wave probe according to an operation of a probe selecting switch. CONSTITUTION: Three probes are aligned in a probe case(10) capable of radiating an ultrasonic wave in a thickness direction of a welding part. A sub cable(20) is provided to transmit information regarding ultrasonic wave signals. The sub cable(20) has a probe cable(21) formed at both sides thereof with an adapter and a protective cable(22) for protecting the probe cable(21). A probe selecting switch(30) is connected to the adapter in order to transfer the ultrasonic wave signals. A main cable(40) is connected to one side of the probe selecting switch(30). An ultrasonic wave probe(50) is connected to an adapter installed at one side of the main cable(40) so as to individually analyze and display the ultrasonic wave signals.

Description

Multi-scanning ultrasonic inspector for weld zone

The present invention relates to an ultrasonic multi-scanning flaw detector for a welding part, and in particular, the ultrasonic flaw detector selectively distinguishes each ultrasonic signal scanned by the welding part by a probe combination case formed by arranging at least one or more ultrasonic probes at a calculated proper distance. The present invention relates to an ultrasonic multi-scanning flaw detector for a welded portion configured to display each of the signals through.

Ultrasound is a high frequency that is over the range of human audible sound (20 ~ 20000Hz). Ultrasound is a non-destructive test that detects surface and internal defects by sending high frequency sound waves into the material to be inspected.

When ultrasonic waves are delivered to the test object by using the ultrasonic waves, it proceeds inside the test body along with the loss of energy, and by analyzing the amount of energy reflected from the discontinuity existing inside and the time of the ultrasonic wave, the position and size of the discontinuity can be accurately determined. There is a number. Ultrasonic examination is a method to check the discontinuity inside the test specimen. It is most widely used with radiographic examination.However, it can be easily inspected even if the thickness of the specimen is thick. have. The information that can be obtained during ultrasonic examination is made by reflection, refraction, diffraction, and interference by the property of ultrasonic waves, reflection from the discontinuity in the test body, reflection at the interface between solid and gas, and reflection at the interface between solid and liquid Pulse-reflection through is mainly used.

Ultrasonic testing in the industrial field is used to detect laminations, cracks and inclusions contained in the discontinuities of the base material as well as to detect pores, cracks, inclusions and fatigue cracks that may occur during processing (welding, casting, etc.) or during use. Used. In addition, it can be used in many fields ranging from steel as well as bridges made of non-steel materials, steel structures, shipbuilding, pressure vessels, and general mechanical parts.

Until now, many types of ultrasonic flaw detectors and probes have been manufactured. For example, the dual transducer has two vibrators arranged in one transducer case to transmit ultrasonic waves on one vibrator and receive reflected ultrasonic waves on the other vibrator. In addition, the tamdom-injected probe has two transducers in one pair. Like the dual probe, one plays a transmitting role and the other performs a receiving role. To introduce another, the phased array transducer is similar to the present invention, but this is also fundamentally different from the present invention. A phased array transducer has a set of transducers, so it can be said that there are as many ultrasonic flaw detectors as there are transducers. That is, since the ultrasonic signals received by each vibrator are analyzed and synthesized by a specific software built-in computing device, the cost of the equipment is quite expensive.

On the other hand, ultrasonic inspection has a tendency to increase defect coverage because the defect detection ability and inspection time is less than other non-destructive inspection. This is a useful ultrasonic test, but this method also has inherent problems. In other words, ultrasonic inspection requires a highly skilled technique unlike other inspection methods. Therefore, the most suitable inspection method for the weak parts of pressure vessels and other structures is ultrasonic inspection, but it requires highly skilled techniques. There is room for thought. Second, the ultrasonic flaw detection is carried out by zigzag scanning of the weld bead. However, the larger the inspection area, the longer the inspection time is, so the concentration of the inspector is lowered, which may adversely affect the judgment of the joint. Thirdly, in order to solve the time loss caused by zigzag scanning, multi-channel multi-detector flaw detectors and techniques are currently used, but special programs are installed in the ultrasonic flaw detectors. As it is sold on the market at a high price of more than 200 to 300 million units, there are many problems in practicality.

Accordingly, an object of the present invention is a transducer combination case formed by arranging at least one ultrasonic transducer at an appropriate distance calculated according to the beam spread angle and the dice on the principle that ultrasonic interference does not appear on the ultrasonic flaw detector when a plurality of cables are combined. To provide an ultrasonic multi-scanning flaw detection apparatus for a welded portion configured to independently display each ultrasonic signal through the ultrasonic flaw detector according to the operation of the transducer selection switch for selectively distinguishing each ultrasonic signal scanned by the welding portion by have.

1 is a view showing the configuration of the ultrasonic multi-scanning scanning apparatus according to an embodiment of the present invention briefly.

2A illustrates beam dispersion of a transducer in accordance with an embodiment of the present invention.

Figure 2b is a view showing the size of the apparent oscillator according to an embodiment of the present invention.

Figure 3 is a view showing a beam incident from the probe with a proper distance with the welding portion according to an embodiment of the present invention.

4 is a view showing a beam incident to the welding portion in the plurality of transducers according to an embodiment of the present invention.

5 is a view showing a transducer combination case according to an embodiment of the present invention.

6 is a view showing a transducer selection switch according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

1: welding part 10: transducer combination case

11: first probe 12: second probe

13: 3rd probe 21: probe cable

30: transducer selection switch 40: main cable

50: ultrasonic flaw detector

Ultrasonic multi-scanning flaw detection apparatus for welding to achieve the above object of the present invention, the scanning line so as to place at least one or more probes, respectively, spaced at a calculated proper distance and to scan the ultrasonic wave as a whole in the thickness direction of the weld A transducer combination case that can be varied; A probe cable connected to one side of each transducer and having adapters at both sides to transmit information related to an ultrasonic signal; It is characterized in that it comprises a transducer selection switch connected to the adapter provided on one side of each transducer cable to select a desired transducer to transmit an ultrasonic signal, the transducer is characterized in that the tilt angle transducer The transducer selection switch may be attached to a welding member by forming a magnet on a lower surface thereof, and may be made of a protective cable surrounding the outer side of each transducer cable so that the probe cable may be integrated. It is further connected to one side of the transducer selection switch and the main cable provided with an adapter on both sides so as to transmit ultrasonic signals that do not interfere or cancel each other, and is connected to the adapter provided on one side of the main cable Independently detect the ultrasonic signal detected by the transducer Output will now be preferably comprising an ultrasonic flaw detector provided to the display as a whole.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the present invention.

1 is a view showing a brief configuration of the ultrasonic multi-scanning scanning apparatus according to an embodiment of the present invention. Referring to Figure 1, the three combination transducers (hereinafter, referred to as the probe) are arranged to be spaced apart by each calculated proper distance and the transducer combination case 10 formed so as to be able to scan the ultrasonic wave as a whole in the thickness direction of the weld And a probe cable 21 having an adapter on both sides and the probe cable 21 which are connected to one side of each probe so as to transmit information related to an ultrasonic signal, so as to increase the work efficiency during the inspection. Sub-cable 20 consisting of a protective cable 22 surrounding the outer side of each probe cable 21, and connected to the adapter provided on one side of each probe cable 21 to select the desired transducer to transfer the ultrasonic signal The transducer selection switch 30 and the transducer selection switch 30 which are formed to be connected to each other, are connected to one side of the transducer selection switch 30 to transmit ultrasonic signals which do not interfere with each other. It is connected to the main cable 40 having an adapter on both sides and the adapter provided on one side of the main cable 40 so that the ultrasonic signals detected by the respective probes do not interfere with each other. Each of them is formed of an ultrasonic flaw detector 50 formed to be independently analyzed and displayed as a whole.

Figure 2a is a diagram showing the beam dispersion of the transducer according to an embodiment of the present invention.

First, the beam dispersion is briefly described. In the far sound field, the intensity of the reflection instruction from the reflector decreases exponentially with increasing distance. In the far sound field, the intensity of the indication decreases exponentially with the beam spread. For reasons of over-attenuation, the intensity of the beam energy decreases as the distance from the transducer increases, which is related to the strength of the sound wave at some point, and the first scan when a certain amount of energy returns to the transducer. The reduced amount is received, and the loss of this energy is called attenuation. The main causes of the attenuation are scattering and absorption, and are only mentioned in the far field, because the near field effect sufficiently offsets the attenuation effect in the near field. .

The beam dispersion does not start from the vibrator plane, and since the energy is concentrated in the central axis from the initial intensity generation in the near field, it can be regarded as a focused vibrator rather than a planar vibrator. Therefore, the dispersion of the beam is not considered in the near sound field.

The beam dispersion angle in the far sound field

------ (Eq. 1)

Can be expressed as Is the dispersion angle of the beam, Is the wavelength, f is the frequency, d is the diameter of the vibrator, and V is the speed.

Therefore, we found that the dispersion angle is determined by the diameter and wavelength of the vibrator. In other words, as the wavelength decreases (frequency increases), the angle of dispersion of the beam decreases, and as the diameter of the oscillator increases, the angle of dispersion of the ratio decreases. For example, this does not mean that a 20 mm diameter oscillator has a smaller beam than a 10 mm diameter oscillator, but at the same frequency, the dispersion angle of the 10 mm oscillator is larger. As shown in FIG. 2A, the angle between the center axis of the vibrator and the line connecting the boundary of the beam ending in the near sound field and the central axis is the beam dispersion angle. The transducer used in the present invention had a frequency of 4 MHz, a speed of 3230 m / s, and a diaphragm diameter of 10 mm. A square probe was used.

On the other hand, the vibrator described above is a description of the vibrator of the vertical probe, so consider the case of Figure 2b.

Figure 2b is a view showing the size of the apparent oscillator according to an embodiment of the present invention.

Since the beam dispersion angle for the vertical probe described in 2a is shown in the present invention, the rectangular probe will be used. Therefore, the following case should be considered. First, the method of flaw detection using ultrasonic waves traveling at an angle with respect to the flaw face of the test specimen is called a square method, and a transverse wave is generally used.

Since the angle of incidence is greater than the critical angle with respect to the refracting wave in the rectangular probe using the shear wave, only the shear wave propagates normally in the longitudinal wave or the test sample in the wedge or the contact medium.

The sound field of the square transducer is complicated by the presence of the wedge and the influence of the angle of refraction at the interface between the wedge and the test specimen, but in brief, the longitudinal wave sent from the square probe into the wedge reflects partly at the interface with the specimen. Bends. In other words, to know the sound field of the refraction transverse wave used for the square flaw detection, the apparent size of the vibrator seen in the test specimen should be known. The sound velocity of the longitudinal wave in the wedge is generally slower than the sound velocity of the transverse wave in the test specimen. Therefore, even in the case of flaw detection, geometrically, as shown in FIG. Means that the size is smaller than the original size.

The apparent size of the oscillator 2g, the original size of the inclination angle of 2a, 2a , Refraction angle Then we can derive the following equation.

---- (Eq. 2)

As the angle of refraction increases, the apparent size of the oscillator decreases with the apparent shrinkage of the rectangular wave transducer used in general.

In the present invention, it was applied to the beam dispersion angle of Figure 2a according to the reduction ratio in Figure 2b.

3 is a view showing a beam incident from the probe at a proper distance from the welding portion according to an embodiment of the present invention. Referring to FIG. 3, the ultrasonic wave is incident while being dispersed, not outgoing a light beam having a predetermined thickness like a laser. Therefore, in view of the beam dispersion according to the reduction ratio of the incident beam with respect to the inclination angle as shown in FIGS. 2a to 2b, FIG. 3a shows the center axis of the weld to detect the discontinuities at a depth of 15 mm. Three transducers are placed at a distance of 31 mm, 39 mm, and 49 mm, respectively, and ultrasonic waves are positioned at the positions of the transducers. 3b shows three incident probes arranged at a distance of 19 mm, 24 mm, and 31 mm from the central axis of the weld zone to detect discontinuities at a depth of 9 mm inside the test specimen. Ultrasound at the position of the transducer The case of inclined incidence is shown.

4 is a view showing a beam incident to the welding portion in the plurality of transducers according to an embodiment of the present invention. As shown in Figure 4 Considering the beam spread angle of the transducer and the position of the transducer, When the beam propagation angle of the probe is calculated and the first, second, and third transducers 11, 12, and 13 are arranged at a proper distance calculated within the range of 0.5 SKIP point, the entire scanning is performed on the welded part 1 of the subject. The SKIP point refers to the point where the beam center axis reflects and reaches from the rear side in the rectangular flaw detection.

Same as above According to the beam spread angle of the probe, when the distance between the first transducer and the second transducer is 15mm, and the distance between the second transducer and the third transducer is 16mm, the end portion of the test specimen having a thickness of 15mm, that is, the thickness direction Can be injected as a whole.

5 is a view showing a transducer combination case according to an embodiment of the present invention. The transducers were constructed based on the data in 2 to 3 above. As shown in FIG. 3, a fixing frame 100 having a predetermined thickness in the form of a depression is formed, and a screw hole 111 is formed on one side wall of the fixing frame 100, and a first probe 11 is formed on the other inner wall. At the same time, the screw hole 111 is provided with a first butterfly bolt 112 having a crimping portion 113 formed at an end thereof, and the first screw bolt 112 is screwed into the screw hole 111. The first probe 11 is pressed against and fixed to the other inner wall of the fixing frame 100 while 112 and one side of the first probe 11 are in contact with each other.

In addition, while maintaining a predetermined distance from the first probe 11, the screw holes 211 are formed on both side walls of the fixing frame 100, and the second probe 12 is disposed in the middle of the bottom surface of the fixing frame 100; At the same time, the screw holes 211 formed in the both side walls are provided with two second butterfly bolts 212 provided with a crimping portion 213 at the ends, and the two second screw bolts 212 each have screws on both sides. The second probe 12 is pressed and fixed in the middle of the fixing frame 100 while being inserted into the hole 211 while contacting each of the pressing portions 213 and the weak side surfaces of the second probe 12.

In addition, the screw hole 311 is formed on one side wall of the fixing frame 100 to which the first probe 11 is fixed in a point symmetrical shape with the first probe 11 while maintaining a predetermined interval with the second probe 12. And a third butterfly bolt 312 formed at the end of the screw hole 311 at the same time as the third contactor 13 is disposed at the inner wall of the other side, and the third screw bolt 312 is formed at the end thereof. 312 is screwed into the screw hole 311 and the third probe 13 is pressed against the other inner wall of the fixing frame 100 while abutting the pressing part 313 and one side of the third probe 13 It is formed to be fixed. In addition, the fixing frame 100 may be manufactured in a detachable form and may be used as an integral type in a mold made of a mold for convenience of work.

The bottom surface of the transducer combination case 10 formed by the comprehensive application of the refraction angle, skip (SKIP) distance, beam spread, incidence point, approach limit distance, the radius of curvature of the test material as described above. While maintaining the proper distance with the welding unit 1 is to transmit the ultrasonic signal according to the flaw detection by the first, second, third probes (11, 12, 13) through the probe cable (21).

6 is a view showing a transducer selection switch according to an embodiment of the present invention. Referring to FIG. 6, a sub cable 20 connected to the first, second and third probes 11, 12, and 13 is connected to one side, and a main cable connected to the ultrasonic probe 50 on the other side. 40 is connected, and the upper part is provided with three switches, and each switch is comprised so that it may be selectively energized with the probe cable 21 connected to the said three probes 11, 12, and 13, respectively. The sub cable 20 and the main cable 40 were provided with adapters at the ends to be detachable.

Due to the selective operation of the switch provided in the probe selection switch 30, ultrasonic waves according to the flaw detection by the first, second and third transducers 11, 12 and 13 of the transducer combination case 10 described in FIG. The signal is transmitted to the ultrasonic flaw detector 50 through the main cable 40 through the sub cable 20 to display the ultrasonic flaw signal on the screen.

As described above, even when the flaw detection signal of the first, second, and third probes 11, 12, and 13 is transmitted to one cable (here, the main cable 50), the ultrasonic signals are displayed on the screen of the ultrasonic flaw detector, but they interfere with each other. Independent signals can be obtained without any phenomenon.

As described above, the ultrasonic multi-scanning flaw detection apparatus for welds according to the present invention is a technical problem of the ultrasonic flaw detection apparatus, which is a non-destructive inspection equipment, and the prolonged inspection time due to the demand for highly skilled technical skills and the zigzag scan during the square flaw detection. As a result of solving the problems such as the bad influence on the judgment of the joint due to the reduced concentration of the inspector according to this, more efficient inspection is possible, the manufacturing price of the equipment can be lowered, and the compatibility is excellent, the ripple effect will be great. Due to the present invention, it will be very obvious that the diagnosis, autopsy technology support, production, and performance inspection greatly contribute to the improvement of the inspection technology by applying the multi-scanning apparatus.

The present invention is not limited to the above-described embodiments, and it will be apparent that many modifications are possible by those skilled in the art within the technical spirit of the present invention.

Claims (6)

A transducer combination case arranged to space the at least one transducer at a predetermined distance and varying the scanning line to scan the ultrasonic wave as a whole in the thickness direction of the welded part; A probe cable connected to one side of each transducer and having adapters at both sides to transmit information related to an ultrasonic signal; Ultrasonic multi-scanning scanning device for a welded portion comprising a probe selection switch is connected to the adapter provided on one side of each probe cable to select a desired transducer to transmit the corresponding ultrasonic signal. The ultrasonic multi-scanning flaw detector according to claim 1, wherein the probe is a tilt angle probe. The ultrasonic multi-scanning scanning apparatus of claim 1, wherein the probe selection switch is provided with a magnet on a lower surface of the probe selection switch to be detachable from the welding member. The ultrasonic multi-scanning flaw detection apparatus according to claim 1, wherein a protective cable is formed to surround the outer side of each probe cable so that the probe cable can be integrated. According to claim 1, Ultrasonic multiple scanning for the weld, characterized in that further comprising a main cable having an adapter on both sides connected to one side of the transducer selection switch to transmit the ultrasonic signals that do not interfere with each other Flaw detector. The welding part of claim 1, further comprising an ultrasonic flaw detector connected to an adapter provided at one side of the main cable, the ultrasonic flaw detector configured to independently display and analyze the ultrasonic signals detected by the respective probes. Ultrasonic Multi Scanning Scanning Device for.