Peaks pass through the gates

NDTne newequipment another ultrasonic couplant just introduced by the same company. The Ultrasonic water baths are now on the couplant comes in three viscosities. It market which are designed for laboratory has a sulphur content of less than work or testing small parts. The small 0.0005% and halogens content less 1180 x 533 x 330 mm stainless steel than 0.0004%. It contains no petroleum tank is built with an underwater light products and no cellulose. It is quick and a drain (Fig. 1), A pump recircudrying, does not form a film and does lates the water through a replaceable not interfere with subsequent penecartridge filter while a surface skimmer trant or magnetic-particle inspection. removes scum. The testable area is It operates at -- 2°C to 150°C. Ultragel 483 x 260 mm with a scan length II comes in 340 ml and 4.4 and 22 1 114 - 267 mm with 25 mm increments. containers: Sonagel in 230 ml, 4.4, 22, The transverse scan speed is continu66 and 240 1. Echo Laboratories, ously variable between 25 - 250 mm s-I . Box 297, Titusville, Pennsylvania The longitudinal index is driven by a 16354, USA. stepper motor through a screw-thread drive. The index increment is adjustable in 0.025 mm steps from 0 . 0 2 5 25.3 ram. The automat;; scan index is selected by a switch. The vertical drive is by hand through rack and pinion. The transverse and longitudinal drives are through spiroid gear and pinion. The maximum angle is 40 ° either side Fig. 2 Gated peak detection is a useful aid of the vertical. The recorder gives a 1 : 1 in ultrasonic flaw location recording to a maximum of 260 x 413 ram. The machine runs off 115 V, Peaks pass through the gates 60 Hz, 3.5 A mains. TekTran, Box 406, Investigation of the characteristics of Lancaster, Ohio 43130, USA. ultrasonic transducers as well as flaw detection could benefit from a gated peak detector now on the market (Fig. 2). The Panametrics 5052 GPG-1 generates a voltage output proportional to the peak amplitude of the highest ultrasonic waveform within a selectable gate window. The device handles voltage input in the range 20 m V - 1 V and 200 m Y - 1 0 V for a dynamic range of 34 dB. It works with a range of ultrasonic frequency from 0 . 1 - 1 5 MHz. The output linearity is claimed to be Fig. 1 An ultrasonic immersion bath is a use- -+ 5% of full scale over the dynamic ful addition to an ultrasonic flaw detector range. The response time is 1 pulse for frequencies under 5 MHz, 8 pulses for 5 - 1 0 MHz and 10 pulses over 10 MHz. Jelly couples ultrasound The gate delay range is 0 . 1 - 2 0 0 / I s and A temperature range of - 3 4 to 146°C the gate width is 0.1-200/~s, both conmeans an American couplant now on tinuously variable. The blank time can the market is useful in all but the coldbe adjusted to up to 100/~s after the est weather. The residue is less than 1% main bang. The device measures weight and halogens content is under 115 x 215 x 330 mm and runs off US 0.002% and sulphur content less than or European mains. Panametrics, 221 0.001% for this slow drying highCrescent Street, Waltham, Massachusett~ wetting gel, Ultragel II. Sonagel is 02154, USA.

Ultrasonic bath scans the parts

NDT I N T E R N A T I O N A L . OCTOBER 1976

s

U K eddy-currents reach U S A British eddy-current ndt equipment is now on sale in the United States through the agency of Balteau Electric Corporation. The Alcoprobe, which gauges the thickness of non-ferrous metals, is already well known as an aerospace instrument (Fig. 3). The 2.2 kg battery-powered portable instrument is used to measure corrosion, to inspect double skins and to sort metals. It has an analogue display and a visual alarm. The other instrument is the 2.27 kg Eddyprobe, is also battery-powered and also has an analogue display (Fig. 4). It is designed to detect and measure surface cracks in austenitic, ferrous and non-ferrous metals. The claimed minimum crack depth detectable is 0.05 ram. The instrument is supplied with two probes, three test blocks and three oscillator circuit boards. Both instruments are made by Inspection Instruments (NDT) Ltd of London UK.

Balteau Electric Corporation, 63 Jefferson Street, Stamford, Connecticut 06902, USA.

Fig. 3 Aeronautical engineers use the Alcoprobe to seek out corrosion attack on aircraft

Fig. 4

British eddy-current crack

detection crossesthe Atlantic

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