CONTROLLED FLOW EXCAVATION

With the recent acquisition of Rotech Subsea, Reef Subsea is able to offer to its clients from the Oil & Gas and Renewable industries one of the world’s largest capabilities in seabed dredging and excavation services. They will range from the precise seabed operations of Scanmudring machines (mainly Scanmachine and Scancrawler) to the controlled flow excavation capabilities of Rotech Subsea systems (mainly T8000 and T4000).

scan-rotech 

The T8000

t8000-image


The Rotech T8000 is one of a range of patented subsea excavation tools operated by Rotech Subsea Limited. The Rotech tools are currently the “state of the art” in controlled flow technology, excavating with a high speed but low pressure column of water.

Key advantages include:

  • Non-contact method of excavation providing high levels of safety for sensitive subsea structuresand pipelines.
  • Excellent performance in wide variety of seabed materials, including stiff clay.
  • Straightforward deployment with minimal deck space requirements.
  • Speed and ease of mobilisation. Everything is designed to fit into 20’ containers and hasbeen flown to several projects in the past.

Uses

The Rotech T8000 can be used for a wide variety of subsea excavation requirements, such as:

  • Pipeline, umbilical and cable trenching, pre-trenching or deburial.
  • Pipeline free-span remediation.
  • De-burial of subsea templates, well-heads or jacket members, from seabed materials, mudslides or drill cuttings.
  • Salvage of dropped equipment or vessels.
  • Removal of rock dump.
  • Site preparation for subsea installations
  • Civil excavation works, including harbour/berth clearance

Excavation Method

The Rotech T8000 excavation tool generates a large volume column of water travelling vertically down to the seabedat a velocity of up to 10 meters per second. The effect of up to 8 cubic meters of water per second hitting the seabed at this speed creates a powerful excavation force capable of breaking up stiff clays.

The T4000

t4000-image

   

The Rotech T4000 is one of a range of patented subsea excavation tools operated by Rotech Subsea Ltd. The Rotech tools are currently the “state of the art” in controlled flow technology, excavating with a high speed but low pressure column of water.

Key advantages include:

  • Non-contact method of excavation providing high levels of safety for sensitive subseastructures and pipelines.
  • Excellent performance in wide variety of seabed materials, including stiff clay.
  • Straightforward deployment with minimal deck space requirements.
  • Speed and ease of mobilization. Everything is designed to fit into 20’ containers and hasbeen flown to several projects in the past.

Uses

The Rotech T4000 can be used for a wide variety of subsea excavation requirements, such as:

  • Pipeline, umbilical and cable trenching, pre-trenching or deburial.
  • Pipeline free-span remediation.
  • De-burial of subsea templates, well-heads or jacket members, from seabed materials, mudslides or drill cuttings.
  • Salvage of dropped equipment or vessels.
  • Removal of rock dump.
  • Site preparation for subsea installations.
  • Civil excavation works, including harbour/berth clearance, channel maintenance and sitepreparation for sea defense works.

Excavation Method

The Rotech T4000 excavation tool generates a large volume column of water travelling vertically down to the seabed at a velocity of up to 10 meters per second. The effect of up to 4 cubic meters of water per second hitting the seabed at this speed creates a powerful excavation force capable of breaking up stiff clays.

More tools to come soon.