JB/T 4008-2020 (English Version) PDF

Scope: This standard specifies the general rules that should be followed when conducting ultrasonic longitudinal wave direct flaw detection on the inspected object using liquid and other liquid coupling methods. When using the liquid erosion ultrasonic pulse echo method for longitudinal wave direct flaw detection, a single-chip probe that can work in liquid (usually water) is usually used as a transducer for transmitting and receiving high-frequency ultrasonic pulses. Through the liquid medium, the probe emits ultrasonic waves vertically into the object to be inspected. When there are reflectors inside the material (including defects and other objects that can reflect ultrasonic waves), the ultrasonic energy will be reflected back from there, received by the probe, and converted into an electrical pulse signal. After being amplified by the electronic instrument, it will be pulsed on the light response screen. The wave form is displayed. According to the presence or absence of ultrasonic echo, the amplitude of the echo and the range in which the echo occurs, the presence, depth, position and size of the reflector can be judged. Defects and material attenuation can also be judged based on the amplitude of the back wave weakening.

JB/T 4008-2020 history

2020 JB/T 4008-2020 Recommended practice for immersed ultrasonic testing by the reflection method using pulsed longitudinal waves
1999 JB/T 4008-1999 Recommended practice for immersed ultrasonic testing by the reflection method using pulsed longitudinal waves