Thickness Measurement on Internally Corroded Metals

Using Dual Element Transducers

One of the major applications of the 45MG is measuring the remaining thickness of pipes, tubes, tanks, pressure vessels, ship hulls, and other structures affected by corrosion or erosion. Dual element transducers are most commonly used for these applications.

• Automatic Probe Recognition for standard D79X series dual element transducers
• Calibration Doubling warning when echo doubling may occur during calibration
• The Echo-to-Echo / THRU-COAT® option allows for measurements on painted and coated surfaces
• High temperature measurements; up to 500 °C (932 °F)

B-scan Mapping (Time-based)

The 45MG gauge B-scan feature converts live thickness readings into cross-sectional images drawn on the display. This standard feature is very helpful in viewing the changes in thickness measurements over a distance. The B-scan is activated as soon as the transducer makes contact with the surface of the material. The Freeze Minimum function is used to display the minimum thickness of the scanned area. The optional 45MG datalogger can store up to 10,000 thickness readings in a single B-scan.

Indoor display setting, B-scan mode

High Temperature Surfaces

The 45MG is ideally suited for making stable thickness measurements on hot material surfaces (up to 500 ºC or 932 ºF) with the D790 series transducers (D790, D790-SM, D790-RL, and D790-SL). The Zero Compensation feature of the 45MG enhances the accuracy of measurements on hot surfaces by compensating for temperature changes in the transducer delay line due to thermal drift.

Echo-to-Echo

The gauge displays the true metal thickness and ignores the thickness of the coating layer, using multiple back-wall echoes:

• Auto Echo-to-Echo
• Manual Echo-to-Echo (with A-scan option only) that allows:
  • Gain Adjust
  • Extended Blanking
  • Echo Blanking

THRU-COAT Technology

Uses a single back-wall echo to measure true metal thickness. You can display the metal and coating thicknesses, each adjusted for their correct material sound velocities. There is no need to remove paint and coatings from surfaces. THRU‑COAT measurements use the D7906-SM, D7906‑RM, and D7908 dual element transducers.