Ultrasonic equipment

The standards concerning the verification of ultrasonic equipment for non destructive testing, which are currently applicable in European countries consist in texts from different origins, such as German (DIN) British (B.S.), Italian and French (AFNOR). 

The HILL-SCAN 30XX boards can be used in different PCs. Desktop- and tower-PCs as well suited for laboratory uses. For in-field inspections rugged notebooks and portable PCs are advantageous. A typical portable system is shown in Fig. 2 (USPC 3010), used in MUSE (Mobile Ultrasonic Equipment). This portable PC not only contains the boards for ultrasonic testing but also a controller with power supply for stepper motors, so that a manipulator can be connected directly. The MUSE system is enlarged with a water circulation system which enables a local immersion technique" for in-field inspections. A typical result is shown in Fig. 3, which presents a D-scan of a CFRP- component in RTM-techniques. The defect area caused by an impact is clearly indicated. The manipulator is described in [3]. 

Based on the results from the initial experiments ultrasonic equipment and transducers for the scanning system were selected. Also a measuring chamber with transducer fixtures was constructed and manufactured for measurement on the tubes directly on the drawing bench. 

In most ultrasonic tests, the significant echo signal often is the one having the maximum ampHtude. This ampHtude is affected by the selection of the beam angle, and the position and direction from which it interrogates the flaw. The depth of flaws is often deterrnined to considerable precision by the transit time of the pulses within the test material. The relative reflecting power of discontinuities is deterrnined by comparison of the test signal with echoes from artificial discontinuities such as flat-bottomed holes, side-drilled holes, and notches in reference test blocks. This technique provides some standardized tests for sound beam attenuation and ultrasonic equipment beam spread. 

Mason TJ, Lorimer JP (1988) Ultrasonic equipment and chemical reactor design in Sonochemistry theory, applications and uses of ultiasound in Chemistiy. Ellis Horwood, Chichester... 

Ultrasonic irradiation has been shown in laboratory studies [73] to increase dye exhaustion, enabling salt levels to be reduced. However, it seems doubtful whether the higher effectiveness is sufficient to merit development to overcome the problems involved in scaling-up the ultrasonic equipment to bulk-scale processing. For example, in one experiment using 5% salt at 65 °C, ultrasound treatment increased the dye exhaustion from 77% to 82%. 

I 7 Ultrasonic Equipment and Chemical Reactor Design Piezoelectric transducers... 

This is probably the most accessible and cheapest piece of ultrasonic equipment available and it is for this reason that so many sonochemists begin their studies using cleaning baths. 

Planar tomography could be complementarily adopted to indicate cracks and determine their depth propagation with high resolution, while time of flight diffraction (TOFD) has been considered not suitable as a surface crack inspection. Ultrasonic equipment such as phased array technique, on the other hand, allows complete weld inspections, improving, for instance, the separation between back wall and defect indication [10]. 

Advantages and disadvantages of uitrasonic baths. Although the cleaning bath Is the piece of ultrasonic equipment most widely used by chemists. It Is not necessarily the most effective. The advantages of using an ultrasonic bath are as follows ... 

On the other hand, the fact that ultrasonic velocity is independent of droplet size In the low and high frequency limits allows droplet concentrations to be determined without prior knowledge of the droplet size distribution from ultrasonic velocity measurements. Whether measurements are to be made In the low- or high-frequency regime depends on the size of the droplets and the range of frequencies which can be measured using available ultrasonic equipment (typically 0.1-100 MHz). 

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