Leak Detection and Locating Technologies by FUJI TECOM

Water Leaks Create Different Sounds.
Water leaking from an underground pipe normally generates an audible sound due to the water pressure. This leakage sound contains four elements:

1. Water flow sound
2. Impact sound
3. Friction sound of the water against the pipe
4. Pipe vibration sound

Sound from water leaks transmits trrough pipe walls, soil and other factors that effect sound transmission.

Water leaks create vibration and different sound.

Sound intensity increases with water pressure.

Transmission of sound differs depending on materials of pipes.

The higher the frequency of the sound is, the more sound is attenuated (absorbed) in soil.

Factors Affecting to Leaking Sound.

• Water pressure inside pipe
• Type of pipe material and pipe diameter
• Soil type & soil density around the pipe
• Material of ground surface
• Extraneous noises: wind, highways, buildings, vending machine etc.

Water Leak Survey & Pinpointing.

• 1. Water Leak Survey
• - Listen at hydrants, valves, meters and other fittings.
• - If there is abnormal sound, then there may be leak nearby the point.
• - If there is no sound, then there is no leak nearby the point.

• 2. Water Leak Pinpointing
• - Perform only after water leak survy.
• - Detect fittings with louder sound.
• - Put detecting diveces to suspicious points.

• 3. Confirmation
• - Boring.
• - Confirming.

Leak survey at meters.

Water leak pinpointing.

Listening at meter by FSB-8D.

Pipe locator induction method.

External coil for insulated pipe & cables.

Pinpointing.

Visible display of detectors.

Leaking point.

Confirmation survey.