What Does Ultrasonic Inspection Mean?
The use of ultrasonic waves in the detection of intra-material defects starts with a German patent in 1931 for the first time. The first commercial devices began to spread to the industry in 1940 years. The development of electronics has contributed greatly to the development of this technique as a practical examination method. Now, the principle of ultrasonic testing is based on the principle that the elastic waves generated by the probe at the high frequency (0,1-20 MHz) are emitted in the test material environment and are reflected in the probe again after a discontinuity. Ultrasonic inspection is a non-destructive testing method by producing high frequency sound waves using special inspection headers. This method detects invisible errors in the interior of the materials. In addition, ultrasound examination method is used to determine the thickness of the materials, to understand its flexibility and to investigate the grain structure. By word, ultrasound means ultra sound or noise. The ultrasound is referred to sounds that are higher than the vibration frequency 20k Hz. The human ear cannot hear this sound. These sounds are emitted by the vibration frequency, emitted as a vibration movement and detected using special devices.
If electrical voltage is applied to quartz crystal or similar materials, their length will be lengthened or shortened. The ultra sound produced in this way has to be sent into the material to be examined. These sound waves are propagated linearly within the material. If there are points in the material with different properties such as a gap or crack, the intensity of the sound waves reflected from the surfaces of these regions is reduced. This information is evaluated on the oscilloscope screen to detect faulty or faulty areas. Briefly, high frequency sound waves sent into the material are reflected if they encounter any obstacles. Depending on the angle of impact, these reflected sound waves produce wave lines on the screen of the ultrasonic inspection device. The coordinates of the obstacle within the material are calculated according to the position of the reflection. The height of the reflection on the screen also gives an idea about the size of the obstacle.
Two different measurements are made by ultrasonic examination method. Either dimension measurement (such as thickness, height or surface hardness measurements) or the properties of the material are determined (such as grain size, residues, cold and hot process grades, detection of errors and detection of internal stresses). There are superior aspects. For example, errors in materials can be detected in three dimensions. This method is easy to implement. Errors in the material are detected with great precision. No extra consumables are used during the application. Planar errors in particular are detected in a more sensitive manner.
Standards for Ultrasonic Inspection
The ultrasonic inspection method, which allows the inspection and inspection of a finished part or material without destruction, has a wide application area.
During the inspection work, TS EN ISO 2014 Non-Destructive Testing - Ultrasonic Inspection - Transition Technique standard published in 16823 is based. This standard replaces the previously applied TS EN 583-3 standard.
Nowadays, there are many testing and inspection institutions that apply and evaluate ultrasonic examination methods. What is important is that these works are carried out by mechanical engineers who comply with TS EN ISO 9712 Non-Destructive Testing - NDT personnel qualification and certification - General specifications standard (formerly TS 7477 EN 473 standard).
The standards applied in the application of ultrasonic examination technique are:
- TS EN ISO 16810 Non-destructive testing - Ultrasonic inspection - General principles (previous EN 583 standard)
- TS EN 12668-1 Non-destructive testing - Characterization and verification of ultrasonic inspection equipment - Part 1: Devices
- TS EN 12668-2 Non-destructive testing - Part 2: Probes
- TS EN 12668-3 Non-destructive testing - Part 3: Combined equipment
- TS EN ISO 2400 Non-destructive testing - Ultrasonic inspection - Calibration block number: Specification for 1 (previous EN 12223 standard)
- TS EN ISO 7963 Nondestructive testing - Ultrasonic inspection - Calibration block number: Specifications for 2
Our company, TÜRCERT Technical Control and Certification Inc., provides ultrasonic inspection services within the scope of non-destructive inspection services with a competent manager and staff and a strong infrastructure.
Ultrasonic testing (UT) is one of the non-destructive testing methods frequently used in the inspection and inspection of pressure vessels and installations. This method is used to control the material to be controlled with very short pulses and waves using various frequency values. In this way, discontinuities on the surface or inside of the material can be detected. In general, the ultrasonic examination method is used to determine the thickness of the materials. For example, this method is used to understand the dimensions of the paint on the material or the extent of corrosion in the pipe.
The ultrasonic examination method is generally applied on metals and alloys. It can also be applied to composite concrete and wood materials. This method, which does not cause any change in the structure of the substance, is used in many sectors including automotive, aviation and other transportation sectors.
Briefly, the ultrasonic examination method is an effective method for controlling discontinuities in the material with the help of high frequency sound waves. The operating principle of this system is based on the reflection of high frequency sound waves sent into the material in case of an obstacle. The signals reflected according to the collision angle are converted to electrical signals and monitored on the device screen. In this way, the distance from the surface to the discontinuity, or depth and size are determined.
In addition to detection of defects in material, thickness measurements and material classification can be done with this method.
Our company also provides ultrasonic inspection services within the framework of non-destructive inspection services. In these studies, the relevant legal regulations, the standards and test methods published by domestic and foreign organizations are followed. Here are a few standards that are based on this:
- TS EN ISO 5817 Welding - Steel, nickel, titanium and their alloys melting welded (not including bundle welding) - Quality levels for defects)
- TS EN ISO 11666 Non-destructive testing of sources - Ultrasonic inspection - Acceptance levels
- TS EN ISO 23279 Non-destructive testing of sources - Ultrasonic inspection - Characterization of symptoms in sources
- TS EN ISO 17640 Non-destructive testing of sources - Ultrasonic inspection - Techniques, test limits and evaluation
- TS EN 12680-1 Casting - Ultrasonic inspection - Part 1: Steel for general purpose
- TS EN 10228-3 Non-destructive testing of forged steels - Part 3: Ultrasonic inspection of ferritic or martensitic forging steels
- TS EN 14127: 2011 Non-destructive testing - Ultrasonic thickness measurement
