- The High Definition (HD) series of rings has been developed for applications where higher sensitivity and resolution are required. Such applications typically include interface penetrations, testing under supports and localised pitting.
- Localised defects (such as pits) will be easier to detect at higher frequencies, however, erosion and certain patches of general corrosion are usually easier to detect at lower frequencies using the adjustable modules. In addition, testing at higher frequencies will cause the range to be significantly reduced in situations when there is an attenuative coating or general corrosion. Therefore, the HD rings accept both HD and Adjustable modules to cover the full frequency range depending on the pipe condition and anticipated defect type. However, HD modules cannot be used in standard EFC rings because there are not enough transducer positions to get reliable results.
- The HD inflatable rings are available from 6 inches (nominal pipe size) and above; below this size, HD solid rings are available.