ASTM E 1001 - 99a. Standard Practice for Detection and Evaluation of Discontinuities by the Immersed Pulse-Echo Ultrasonic Method Using Longitudinal Waves

American Society for Testing and Materials (ASTM). 1999, 9 pages.
This practice describes procedures for the ultrasonic examination of bulk materials or parts by transmitting pulsed, longitudinal waves through a liquid couplant into the material
and observing the indications of reflected waves (Fig. 1). It covers only examinations in which one search unit is used as both transmitter and receiver (pulse-echo) and in which the part
or material being examined is totally submerged in the couplant (immersion testing). This practice includes general requirements and procedures which may be used for detecting
discontinuities and for making a relative or approximate evaluation of the size of discontinuities