Patent ID: 8156810

Claim:
A method for determining a presence of and characterizing a defect of a heat fusion joint connecting two pipe segments comprising the steps of: applying an acoustic waveform at a plurality of locations over at least 270 degrees of a circumference of a heat fusion joint fitting disposed around a pipe segment to one of an exterior surface of said heat fusion joint fitting and an interior surface of said pipe segment; measuring a time of flight of a reflected waveform reflected from one of an interior pipe wall of said pipe segment and said exterior surface of said heat fusion joint fitting at each of said locations; determining each measured minimum time-of-flight location on said circumference and each measured maximum time-of-flight location on said circumference; and determining from each said measured minimum time-of-flight location and each said measured maximum time-of-flight location whether or not said heat fusion joint is a defective heat fusion joint.