My LinkedIn article on the Combiphon Plastic Pipe Locator

Acoustic Pipe Locating

Anyone who has used an acoustic leak detector can tell you they can hear a leaky pipe underground. You can also maximize the sound when you are directly over top of the pipe and/or leak to locate it laterally. Therefore, it is possible to find the location of a noisy leaking pipe with most modern leak locators. The Sewerin Combiphon system uses this theory to place a different kind of sound on the pipe to allow locating a non-leaking pipe by the noise emanating from it. The Combiphon system starts with a battery operated generator. The generator can control either a "Knocker" for 2 inch and smaller pipe and tubing, or a "Stopper" for larger water mains. either accessory induces a safe locatable sound on the pipe which can be detected by a typical acoustic pipe locator. The generator has adjustment knobs for both intensity and frequency of the sound generated. Most acoustic leak detectors will work to find the sound, but Sewerin has the A200 and AC200 leak locators optimized with a special software just for acoustic pipe locating. To locate the pipe, the operator sweeps perpendicular across where the pipe is suspected to be located and marks the pipe at the highest sound intensity reading..."

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