In this non-destructive test method, high frequency sound waves are propagated into a material, modified by possible material anomalies with the resulting attenuated wave detected and interpreted.
Ultrasonic Thickness Gauging:
Ultrasonic thickness gauging is a widely used nondestructive test technique for measuring the thickness of a material. It is a fast, reliable and versatile test method and requires access to only one side of the test piece. Thickness gauging has become a standard service for offshore facilities, petrochemical plants and shipping industry where baseline surveys and periodic monitoring fit appropriately into an overall asset integrity program. In order to meet the demands of our Customers, TISL has committed itself to providing well trained and certified technicians along with the latest in modern equipment and capability.
Thickness Meters with Data logging capability from Krautkramer Branson with on board Data Recorder and Ultra MATE Thickness Data Management System with colour reporting facilities is available. These units can store up to 80,000 readings and can be download into any PC. These meters also have the advantage of reading steel thickness through coating surfaces without removal of coating.
Remote Tank Crawler:
The UT Crawler is absolutely the fastest method for inspecting remote access areas such as Tank surfaces. Apart from the additional technical capabilities of the crawler, it is also cost efficient since it removes the need for scaffolding. The system utilizes a remotely operated vehicle with magnetic wheels for the inspection of remote areas.The vehicle is operated via a “Joy-Stick” allowing for complete directional control. An ultrasonic transducer is mounted in a shoe fixture which is spring loaded to the material surface. Water is transported to the transducer via a couplant delivery system, allowing the coupling of acoustic energy into the material. The Ultrasonic Flaw detector receives all ultrasonic information regarding thickness as per a normal Ultrasonic Thickness Survey. A distance encoder wheel is also attached to the vehicle to transfer positional information to the Analyst system. The laptop receives information from both the UT Scanner and the distance encoder and translates this into a real time B-Scan presentation of the item being inspected.
Ultrasonic Shear Wave:
Of all the applications of industrial ultrasonic testing, flaw detection is used to detect hidden cracks, voids, porosity, and other internal discontinuities in metals, composites, plastics, and ceramics. High frequency sound waves are reflected from flaws producing distinctive echo patterns that can be displayed and recorded. Common applications include welds. It is also readily used where radiography is not feasible due to the part geometry and too large a thickness being inspected or when the hazards of radiography cannot be accommodated. It is also used to ensure conformance to relevant specifications or standards where identification and sizing of defects for repair is required.
Ultrasonic Testing for Drill Pipes:
This method is used for performing Shear Wave Ultrasonic inspection of used drill pipe and HWDP slip and upset areas, in compliance with the latest referencing. This inspection is used for the detection of transverse and three-dimensional flaws on the inside and outside surface of the tube. Each scan is recorded digitally on a chart
Phased Array Ultrasonic Testing (PAUT):
Ultrasonic phased array systems can potentially be employed in almost any test where conventional ultrasonic flaw detectors have traditionally been used. The main advantage of Phased Array inspection over conventional UT flaw detection is the availability of multiple frequencies, multiple angles that are available in one probe with the machine having the ability to calibrate and set this array of options all in one inspection. The benefits of phased array technology over conventional UT comes from its ability to use multiple elements to steer, focus and scan beams with a single transducer assembly. Beam steering, commonly referred to as sectorial scanning, can be used for mapping components at appropriate angles. This can greatly simplify the inspection of components with complex geometries. The small footprint of the transducer and the ability to sweep the beam without moving the probe also aids inspection of such components in situations where there is limited access for mechanical scanning. Sectorial scanning is also typically used for weld inspection. The ability to test welds with multiple angles from a single probe, greatly increases the probability of detection of anomalies. PAUT can also be effectively used to profile remaining wall thickness in corrosion survey applications. Electronic focusing permits optimizing the beam shape and size at the expected defect location, thus further optimizing probability of detection. The ability to focus at multiple depths also improves the ability for sizing critical defects for volumetric inspections. Focusing can significantly improve signal-to- noise ratio in challenging applications, and electronic scanning across many groups of elements allows for C-Scan images to be produced very rapidly.
Time of Flight Diffraction (TOFD):
In a TOFD system, a pair of ultrasonic probes sits on opposite sides of a weld. One of the probes, the transmitter, emits an ultrasonic pulse that is picked up by the probe on the other side, the receiver. In undamaged pipes, the signals picked up by the receiver probe are from two waves: one that travels along the surface and one that reflects off the far wall. When a crack is present, there is a diffraction of the ultrasonic wave from the tip(s) of the crack. Using the measured time of flight of the pulse, the depth of a crack tip can be calculated automatically by simple trigonometry. This method is even more reliable than traditional radiographic, pulse echo manual and automated weld testing methods.