contrôle d'assemblage par impédance ultrasonore

CONT: Seam Testing Methods... There are number of procedures available which have applicability on different geomembranes ... the ultrasonic impedance plane method works on the principle of acoustic impedance. A continuous wave of 160 to 185 kHz is sent through the seamed liner and a characteristic dot pattern is displayed on a CRT screen. Calibration of the dot pattern is required to signify a good seam; otherwise, it is not. The method has potential for all types of geomembranes but still needs additional development work.