ULTRASONIC TECHNOLOGY IN NDT
High-speed Ultrasonic (UT) Systems enable a full volumetric examination of materials and are designed to detect surface, subsurface, internal and dimensional flaws.
This type of testing utilizes high-frequency sound waves that are transmitted throughout the material being tested in order to conduct a thorough inspection.
- Ultrasonic inspection can be used to detect surface flaws, such as cracks, seams, and internal flaws such as voids or inclusions of foreign material. It’s also used to measure wall thickness in tubes and diameters of bars.
- An ultrasonic wave is a mechanical vibration or pressure wave similar to audible sound, but with a much higher vibration frequency. For NDT purposes, the range is usually from 1MHz to 30MHz.
- Depending on the test requirements, these waves can be highly directional and focused on a small spot or thin line, or limited to a very short duration.
Two methods of UT are used for flaw detection – Shear and Compression Wave.
- Shear method uses an angled beam that is usually 45˚. This enables surface and subsurface testing. Surface cracks, seams and near surface inclusions can be detected with the shear method. Shear method can overlap the normal incidence method inspection and result in a 100% volumetric test of the bar.
- Compression is also know as normal incidence. This is the primary internal inspection for bar testing. The transducer is set to exactly enter the bar surface perpendicular to the surface. This inspection method is limited to the entire bar volume except approximately a 3mm thick outer shell.
- MAC offers a wide variety of highly sophisticated UT testing solutions to meet your specific needs.
- MAC’s ultrasonic NDT testing methods will indicate material defects such as longitudinal and transverse cracks, inclusions and other flaws, as well as ID/OD dimensions and dimensional changes such as thickness and ovality.
- The Echomac® Rotary Transducer Assembly provides multiple test configurations for tube or bar up to 500mm in diameter. Available for shear-wave configuration (surface and subsurface defects) and compression-wave configuration (internal defects and dimensions measurements such as wall thickness).
- The Echomac® FD-6 Multi Channel Ultrasonic Tester is a computer-based UT inspection instrument designed for on- or off-line flaw detection, thickness and dimensional measurement.
- The Echomac® FD-6 180mm Phased Array Test System offers high-speed parallel processing to handle a large amount of data and is designed for situations where phased array ultrasonic technology is preferred to conventional rotary ultrasonics. A unique water box design minimizes water loss and bubbles while ensuring that bars are properly centered relative to the transducers.
- As the use of nodular graphite iron material has expanded in recent years for automotive safety parts, ultrasonic velocity measurement provides an industry accepted means of verifying the material integrity of the part. The Echomac® VM measures velocity to assess nodularity in ductile iron cast automotive components. It operates with either full immersion or bubbler couplant technology and can test two parts simultaneously in separate test situations.