42 SERVICES FOR DETECTING DEFECTS IN MATERIALS AND MANUFACTURED PRODUCTS, PRINCIPALLY ELECTRICAL WIRE INSULATION, CASTINGS, PAINTINGS, WELDED JOINTS AND SEAMS, TUBES, AND PIPES, COOLING CIRCUITS, OIL AND GAS LINES, EXCHANGER AND BOILER TUBING, AND FOR DETECTING CRACKS AND LEAKS IN VESSELS AND OTHER CONTAINERS, VARNISH ON PANELS, IMPURITIES IN COPPER WIRE, POROSITY AND CLEFT OF MOLDED PIECES, ADHESION OF COATINGS, SEPARATION OF FABRIC AND ADHESIVE, VIBRATION OF ROTARY EQUIPMENT, WEAR OF TOOLS AND REFRACTORY MATERIALS, GRAIN SIZES, CORROSION, AND THE LIKE