Through transmission was used in the early days of ultrasonic testing and is still used in plate and bar production.
A probe on one side of a component transmits (T) an ultrasonic pulse to a receptor (R) probe on the other side. The absence of a pulse coming to the receiver indicates a defect.
The advantages of through transmission are:
- Less attenuation of sound energy
- No probe ringing
- No dead zone on the screen
- The orientation of a defect does not matter in the way that it does on the pulse echo display.
The disadvantages are:
- The defect cannot be located
- The defect cannot be identified
- The component surfaces must be parallel
- Vertical defects do not show
- The process must be automated
- There must be access to both sides of the component.
Please contact us for more information.