SmartBall was developed by Pure Technologies to tackle a need that had not previously been addressed by existing leak detection technologies, i.e. to provide an accurate, efficient and sensitive means of detecting and locating leaks in large-diameter pipelines [300 mm), or in non-ferrous pipelines.This is a noninterruptive technology, which means that pipelines do not have to be shut down when detecting leaks in a pipeline. Advantages of the SmartBall technology include:

• accurate leak location (I m]
  
• leak location upon data processing
  
• high sensitivity due to sensor proximity to leak (independent of pipe material)
  
• long survey lengths [23 km @ 0.5 m/s flow velocity)
  
• reguires only two 90-mm access ports per survey
  
• can traverse in-line butterfly valves
  
• minimum pipe diameter: 100 mm
  
• distinguishes between multiple leaks in
  
• leak size estimation presented in report
  
• requires flow control at some branch line locations

Pure Technology provides ongoing support to RWS. The training of all Rand Water and RWS technical support staff has been completed successfully.

The Smartball was then piloted on the Rand Water C4 and B4 pipeline: the results were then presented to Rand Water.

How it works

The acoustic signature created by a leak along a pipeline occurs at the point of pressure change. As the SmartBall passes through a leak from a pipeline, the acoustic energy created by the leak is radiated into the contents of the pipeline. The most accurate recreation of a leak occurs when the pressure drop is generated very near the pipeline. If a long, small diameter tube or hose is used to dispose of the water, the output restriction should be where the pipe is attached to the pipeline, not at the far end of the small pipe or hose. The farther away from the pipeline a simulated leak is created, the less accurately it will reflect a real leak. The diameter of the disposal piping used, the number of bends in the piping and even the material used for the piping will also degrade and change the acoustic signature of the leak. Producing a leak at an existing valve along the length of the pipeline is the most likely implementation of imitating a leak.

Using the valve on the pipeline as flow control: When using the existing valve along the pipeline, the pressure drop should occur at the valve mounted on the pipeline. This is an ideal situation since the pressure drop occurs very near the pipeline flow.

Using a separate valve for flow control: If a secondary valve is used as flow control, then the pressure drop will occur at this second valve. The second valve should be located as close to the original valve on the pipeline as possible (within 30 to 60 cm).

If a type of hose or tubing will be used to divert the fluid created by the leak away from the site, in should be sufficient in diameter to avoid restricting the flow of fluid. If the fluid flowing from the end of the hose or tubing is not pressurised, then a significantly sized hose is chosen and there is no restriction on how long the tubing disposing of fluid can be. If it is pressurised, then the flow should be reduced until the fluid exiting the tubing is no longer under pressure. Different flow rates can be stimulated by opening and closing the valve. If desired, this fluid can be collected and measured over a set time periods to obtain a flow rate. This flow rate can then be compared to the SmartBall estimates at a later stage.

A simulated leak can test the SmartBall on how well it can locate a leak along a pipeline, and how well the SmartBall can estimate the size of leaks (if the leak rate of the simulation is known). South Africa is currently classified as a water-stressed country, and water conservation and loss reduction is therefore a critical priority. Using progressive technology such as Pure Technologies SmartBall will most certainly curb water loss.