The C.D.L. Crack Detector and Tube Tester

摘要

The C.D.L. Crack Detector was designed for the detection of cracks in tubes and bars of non-ferrous metals. In operation, it comprises a search probe which is a sliding fit around the bar under test and a portable battery operated instrument. The probe is moved along the bar and flaws are indicated by a lamp set for a predetermined fault level. A meter also gives an indication of minor faults below the threshold set for lamp illumination. The CDL Tube Tester is a development of the CDL Crack Detector designed for the inspection of heat exchanger tubes in situe. The operating frequency has been increased to 1 MHZ to reduce the depth of eddy current penetration in order to eliminate the effect of baffles and tube finning.