Traditional Pipe Leak Detection Techniques
Traditionally the detection of leaks in pressurised pipe networks has relied on indicative information in order for the owners to discover there is leakage on the network.
This has permitted leakage to develop, in turn creating failure events that can be quite spectacular. Inability to reliably detect and to subsequently locate suspected leakage is entirely due to the technologies that were available in the past. Without exception the unsatisfactory focus for detection and location of leaks has been related to volumetric, pressure, flow, temperature and sonic parameters, that have repeatedly proven their limitations.
As network owners reduce pressures in their networks to minimise risks, traditional approaches become even more ineffective. A revolution in leak detection and location is here, one that does not rely on parameters that are difficult to detect, or on complex statistics, so much so it will even work on sewers.
Sonic Limitations
All high resolution pipe leak location (post leak detection) is carried out using sonic methods.
Pressure: Low pressure in the pipes mean that it is not possible to determine the position of leak resulting in dry excavations and wasted cash.
Pipe Material & Diameter: Sonic properties of certain pipe materials and diameters create great difficulty in committing to any excavation.
Background Noise: In cities and on highways sonic techniques are impossible. In the past this has meant testing at night to find periods of quiet. In most modern cities this is no longer practical.
Operator Skill: Training & individual aptitude towards certain tasks means that differing output from different individuals can create uncertainty.
No Definitive Answers: There are no unambiguous results, all have to be evaluated either by humans, or by complex computer driven statistical models.
Slow: Traditional acoustic methods take significant time to complete, even in perfect conditions.
A Revolutionary Pipe Monitoring Technology
The LID method avoids all of the issues of historical leak detection and location techniques by avoiding all traditional parameters and instead directly measuring for leakage in the electrophysical properties of the ground around the pipe.
Benefits of Sensor LID
- Not affected by noise
- Not affected by pressure
- Not affected by pipes
- Not a skilled process
- It is a definitive result
- Testing process very fast
- Multiple leak detection (in close proximity)
Put the LID on network leakage.
Monitoring New Pipe Installations
The best time to install the LID system is at the same time as the pipe itself. Pipes often leak from the moment they are covered for a wide variety of reasons. Installations with new pipes are very low cost and will allow the maximum lifespan of the pipe itself to be. Large pipes require multiple sensing elements.
Sensing Element (SE) positioned on pipe bedding
Installation is simple and unskilled, the sensing element simply needs to be placed close and approximately parallel to the pipe it will monitor.
Easy As: 123
Monitoring Existing Pipe Installations
The LID sensing element is installed at a nominal depth of around 300mm, the path of the sensing element needs to follow the path of the existing pipe beneath.
Metallic Pipes: An electrical connection is made to the pipe and the installation will then behave in the same way as a LID sensing element installed with a new pipe.
Non-metallic Pipes: The LID sensing element is placed to run within the shallow 300mm trench however additional vertical runs are required.
Commissioning & Operation
The commissioning takes place after covering. When connected to the sensing element the system automatically acquires: the GPS coordinates; the exact length of the SE; and a baseline measurement which is stored in a database and associated with an ID chip contained within the buried sensing element.
Either during commissioning or at some point in the future it is recommended that leak simulation tests are carried out. The efficacy of the system is tested and providing the highest confidence. The tests can be achieved using secret valves, soaker pits, or other means to simulate the presence of leakage.
Operation of the system is automated making it simple and fast, each time a transceiver is connected to a sensing element it performs a preprogrammed routine.
ID and GPS position of the sensing element are automatically acquired so that the Leak Location Practitioner does not need to record this information manually. Similarly baseline and any previous measurements are automatically compared, with leak positioning information calculated by linear distance from the GPS position of the measuring station. The average daily testing rate for field testing is around 20km per day.