Penetrant makers branch out

i strain (Fig.3). The type chOsen for any application chiefly depends on the accuracy required, The firm has made systems for cathode-ray tubes and for products made by injection moulding.

Television tames t h e n e u t r o n

The systems comprise a light source, Polaroid filters and an analyser. The light source can be either monochromatic or white depending on the application. The firm also makes holders and jigs for the work piece. Sharpies Photomechanics Ltd, Europa Works, Wesley Street, Bamber Bridge, Preston PR5 4PB, UK Fig.4 The digital dosemeter is small enough to fit in the pocket

Penetrant makers branch o u t

Fig.3 Polarizedlight shows the strains produced in e polycarbonatebeaker made by injection moulding

Ardrox, which makes a range of chemicals and equipment for penetrant testing, is to market an eddy-current crack detector. Ardrox has agreed with the makers, Hocking Associates, to market the device. Hocking Associates designed the crack detector, called the Halec, in collaboration with users of eddy-current instruments. The Halec operates at 3 MHz and it is designed to be rugged. Ardrox claims that cracks down to 0.1 mm deep can be de~cted (Fig.5). It has probes for ferrous and non-ferrous metals and for bolt holes and sorting. It has controls to select the probe, to set zero and adjust sensitivity and monitor alarm. The alarm is audible. The equipment measures 240 x 13 x 105 mm and weighs 2.6 kg. It is powered by rechargeable cells. Ardrox Ltd, Ridgeway, Iver, Bucks, SL0 9JJ, UK

Dose counting by number An American company has introduced a digital dowmeter to be worn in the pocket (FlgA). It records gamma doses in increments of 0.01 mR. It has an electro-mechanical permanent memory and it gives an audible signal for each 0.01 mR of dose. It covers a range from 0.01-100 mR. It is designed to operate off an ordinary 9 V transistor radio battery for over 300 h. It weighs 280 g. It also respondsto x-rays down to 50 keV in energy. Reactor Experiments Inc, 963 Terminal Way, San Carlos, California 94070, USA

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Fig.5 The crack detector can be used to find cracks in castingand forgings

The American subsidiary of a Dutch company has developed a system for televised neutron radiography (Fig.6). The company Old Delft Corporation (ODELCA) is a subsidiary of de Oude Delft of the Netherlands. The system can also be used for x-radiography. The object under test is placed between the source and the imaging system. An integrating device takes the information from the imaging system and drives a television monitor, a display and a video tape recorder. The developers claim a well defined image is produced in a few minutes. Oude Delft has produced x-ray systems in the past to test tyres non-destructively. Odelca, 2735 Dorr Avenue, Fairfax, Virginia 22030, USA

Fig.6 Neutronradiographyshows fuel as it passesthrough the carburettor in the middle of the picture: the image system on the left produces an imageon a remote television monitor

Americans count eddy-current An American company has introduced an eddy-current test instrument with one knob and a digital display. The instrument, the Verimet M1900, can be connected to probes or to coils (Fig,7). The knob switches the instrurnent on and selects the test frequency from0.1, 0.25, 1, 10and 100 kHz. The display shows the eddy-current signal as a number. The instrument weighs 1.1 kg and measures 165 x 95 x 63 ram. The power supply is from rechargeable nickel-cadmium batteries. It was designed for alloy and hardness sorting. K. J, Law Associates Inc, 26325 W Eight Mile Road, Detroit, Michigan 48240, UK

NON-DESTRUCTIVE TESTING. FEBRUARY 1975