A process has been developed for application of a thin, adherent vinyi plastic coating to graphite plates to prevent absorption of coupling fluids'' used in ultrasonic inspection. The plates are preheated and dipped mechanically in a fluid plastisol, and the resulting coating is fused in an infra-red heater. No significant attenuation of ultrasonic impulse results from presence of the coating. After inspection, the vinyl sheath may be easily stripped from the plate. (auth)