The ultrasonic examination is the non-destructive examination method used to determine the volumetric defects within the material without damaging the material with the usage of sound waves.
It is possible to determine the discontinuities within the material by using the ultrasonic examination method as well as the elastic and metallurgical properties of the material through non-destructive methods. In this method, which is based on the principle that the solid materials are good conductors of wave lengths, the material is controlled by using the high-frequency sound waves.
• THE MAIN PRINCIPLE
The high-frequency sound waves are sent to the material by a piezoelectric crystal with the capacity of converting the electrical energy to the mechanical energy and the mechanical energy to the electrical energy.
The transmitted high-frequency sound waves are reflected by the obstacles on the sound way. The signal that is reflected depending on the impact angle, may come to the signal-receiving probe or not. The main points here are the transmittance of the sound waves and the sound waves that meet with faults within the materials which eventually return to the probe as their advancement is stopped. The signal reflected to the receiving probe creates the wave patterns (echo) on the screen of the ultrasonic test device. Depending on the location of the echo, the coordinates of the reflector within the examination piece can be calculated.
• APPLICATION & ADVANTAGES
The suitable frequency is determined based on the microstructural properties of the test piece. A suitable contact liquid (oil, grease, water etc.) shall be used so that the sound waves can penetrate the material when the probe contacts the examination surface. The probe is moved on the examination surface for scanning to observe if there are echoes other than the echoes caused by the geometrical properties of the piece, if any, the locations and heights of such echoes are evaluated for fault analysis.
The most suitable types of waves used for ultrasonic examination are the longitudinal (pressure) and horizontal (shear) waves. When using the normal probes, which have zero degree of inlet angle, the waves that move within the material are longitudinal waves. The angular waves send the transverse waves within the material generally with 45°, 60° and 70° of inlet waves.
Ultrasonic examination is preferred because of the ease of use with the portable devices and the determination capacity during the tests. Especially for the larger work pieces in terms of dimensions, the faults based on planes are much more precisely determined. Thanks to this method the cracks, gaps and some other discontinuities within the piece can be determined.
• OUR APPLICATION FIELDS
The Ultrasonic Examination can be reliably used for all casting, forging and welding seams. We meticulously carry out the determination and reporting processes for the internal body discontinuities, lamination examination in addition to every kind of (T, butt and fillet) welding, casting, forging, rolling piece examinations by using flat and angular probes at various frequencies thanks to our ultrasonic fault detectors.
•THICKNESS MEASUREMENT BY ULTRASONIC METHOD
Thanks to the fact that the ultrasonic waves spread inside at a fixed speed and are reflected from the rear end of the piece, we are able to determine the thickness of various materials by relying upon the principles of ultrasonic examination.
• THE MAIN PRINCIPLE
The ultrasonic thickness measurement principle is similar to the light wave measurement principle. The ultrasonic wave spread by the probe reaches the item that is to be measured and spreads throughout the item. When it reaches the material interface, it is reflected back to the probe. The thickness of the tested material is determined by the correct measurement of the duration of the spreading of the ultrasonic wave throughout the material.
• OUR APPLICATION FIELDS
Various plates and processed pieces can be measured correctly thanks to this method. Moreover, observing various pipes and pressurized containers in scope of the production equipments to track their corrosion degrees is an important part of this method. We offer services to perform the thickness measurements for the pressurized containers of the ships and other sea vessels in addition to the steam boilers of the power stations as well as the petroleum and natural gas pipe lines with our ultrasonic thickness measurement devices to determine the lamination, pitting and formations of discontinuities with reports that include even the smallest details.