06194902 is referenced by 20 patents and cites 86 patents.

A method and system for detecting corrosion on a pipe or a pipeline. An electrical or electromagnetic pulse is transmitted into a pipe or pipeline to travel as a propagating electromagnetic wave along the pipeline to a receiving location. Both the distance traveled from the transmitting and receiving location, and also the time interval for such travel are measured. Velocity of the wave is detected as a means of ascertaining whether corrosion is present. Various embodiments, using both multi-channel and single cables, are used to transmit the detected waves, and the waves are received at a plurality of spaced locations along the length of the pipe or pipeline. For an insulated pipeline, the signals can be received by a directional antenna, and the pulses can be transmitted into the pipeline by means of either an antenna placed directly adjacent to the pipeline or a magnet electrical contact member in direct contact with the pipeline.

Title
Pipe testing apparatus and method using electrical or electromagnetic pulses transmitted into the pipe
Application Number
8/807645
Publication Number
6194902 (B1)
Application Date
February 27, 1997
Publication Date
February 27, 2001
Inventor
Gale D Burnett
9191 Northwood Rd., Lynden
WA, US
John T Kuo
11 Hoffman La., Blauvelt
NY, US
Agent
Hughes & Schacht PS
US
Agent
Robert B Hughes
US
IPC
G01R 31/08
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