UMAC® Wall Thickness Measurement with Ultrasonic Measurement

UMAC® represents a complete line of non-contact ultrasonics based systems for wall thickness measurement and control of pipe, hose, tubing, and cables. The heart of each system consists of a highly developed UMAC® measuring system, interrogating up to 16 sensors at high speed. WALLMASTER systems process data from several ODAC® measuring heads and a UMAC® Wall Thickness and Eccentricity System located immediately after the extruder. Automatic closed-loop control of wall thickness and/or diameter is easily possible.

Ultrasonic Measurement Principle

It is based on the time difference (t2) of the sound echoes from the surface and the inner side of the product. A piezoelectric crystal is excited by a sort electrical pulse. The crystal converts electgrical energy into mechanical energy, i.e. sound waves. When the sound waves encounter a difference in the propagation medium (for instance when passing from water to a synthetic material), a part of them is reflected back to the crystal (echo).
Wall thickness = Sound velocity of material x t2 x 0.5