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Angle Beam Inspection Calculations

When performing an angle beam inspection, it is important to know where the sound beam is encountering an interface and reflecting. The reflection points are sometimes referred to as nodes. The location of the nodes can be obtained by using the trigonometric functions or by using the trig-based formulas which are given below.

  • Nodes - surface points where sound waves reflect.
  • Skip Distance - surface distance of two successive nodes.
  • Leg 1 (L1) - sound path in material to 1st node.
  • Leg 2 (L2) - sound path in material from 1st to 2nd node.
  • qR - refracted sound wave angle.


Skip Distance Formulas
Surface Distance Formulas
Leg 1 and Leg 2 Formulas
Flaw Depth (1st Leg)
Flaw Depth (2nd Leg)