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Optimising position control in shallow water dredging operations

In marine and freshwater environments, shallow water dredging is a process used to remove sediment, debris, and other materials from beaches, harbours, rivers, canals, wetlands and other bodies of water to ensure they remain navigable and healthy for human activity and aquatic ecosystems.

Key challenges

One of the key challenges in shallow water dredging is maintaining precise control over the dredging machine's position to ensure efficient material removal, minimise environmental impact, and reduce the risk of damaging underwater infrastructure.

Unlike deeper dredging operations, where minor deviations might go unnoticed, shallow water projects are often close to shorelines, docks, or other structures where there is limited room for error. This is where position feedback systems come into play, providing real-time data to operators and automation systems to help keep the dredging operation precise and effective.

How linear position sensors work in shallow water dredging

Linear position sensors assist operators in maintaining the correct position, depth, and orientation of the dredging head for efficient and safe operations. They can be used to:

  1. Regulate the vertical position of the dredging head to ensure the equipment operates at the correct depth, optimising material removal and preventing over-excavation.
  2. Control the large mechanical arms or booms used to extend the dredging head into position and adjust its orientation to avoid underwater hazards.
  3. Prevent mechanical wear and reduce downtime by providing accurate information about the movement of components, including the extension and retraction of the hydraulic cylinders that regulate the dredging head.

Specifying linear position sensors for underwater dredging machinery

When selecting linear position sensors for use in shallow water dredging equipment, several key specifications must be met to ensure reliable performance in the harsh underwater environment. Dredging operations often expose sensors to water, mud, sediment, debris, and strong vibrations, so the sensors need to be robust, durable, and resistant to environmental factors.

Summary of key specifications:

  • Environmental sealing: IP68 or higher, with 350 bar pressure resistance.
  • Corrosion resistance: Made from 316 stainless steel or titanium.
  • Temperature range: Operating range of -20°C to +70°C or wider.
  • Vibration and shock: Capable of withstanding high vibrations (5g+ over a wide frequency range) and shocks (up to 40g for general dredging machinery).
  • EMI/EMC resistance: Compliance with EMI/EMC standards.
  • Resolution/accuracy: High resolution (0.01 mm) and accuracy (±0.1%).
  • Connector durability: Waterproof, abrasion-resistant cables and connectors.

Linear position sensors are critical components of shallow water dredging equipment, providing precise and reliable feedback on the movement and position of the dredging head, mechanical arms and other key components. By ensuring accurate positioning, these sensors enable operators to optimise dredging operations, reduce environmental impact, and prevent costly equipment damage.

Positek’s S125 rugged submersible stand-alone linear position sensor is well-suited to this type of application. It is compact and durable with high accuracy and can be customised to suit specific project requirements, ensuring compatibility with various operational needs.  To learn more, please contact sales@positek.com

 

 

Article published on: 21/10/2024

Article last updated on: 21/10/2024