pre-piling template being dropped into the water

Pre-Piling Templates

Delivering custom-engineered pre-piling templates for the fixed offshore wind industry to ensure that jacket foundations are installed efficiently, reliably and cost-effectively.

Fixed-bottom offshore wind turbines can be supported by a number of different foundation options. In water depths of 30m-70m, jacket solutions are a popular choice due to their maturity and use of smaller piles which are easier to install than monopiles. Offshore wind jacket foundation piles are usually pre-installed for scheduling efficiency and the installation is done using pre-piling templates to ensure that the piles are installed in the correct place and within the appropriate tolerances. As a result, pre-piling templates require a precise and intelligent design process to ensure they are fit for purpose.

2H has extensive experience in advanced engineering of complex structures and provides complete design and engineering services for pre-piling templates. Our global footprint and partnerships with local supply chains and fabrication yards around the world mean that we can also undertake the full engineering, procurement and construction scope. We also offer delivery management services, performing the pre-piling template engineering, and managing the procurement, construction and installation scopes on behalf of the contractor.

Design Considerations of Pre-Piling Templates

The primary goal of the pre-piling template is to facilitate the installation of the jacket piles. This is a precise operation and successful installation of the jacket depends on the quality of the pre-installed piling operation. Pre-piling templates therefore generally need a number of secondary features:

  • A levelling and pre-loading system to ensure that the template is orientated and positioned correctly at the turbine location.
  • Surveying and controls functionality to aid with the above.
  • Project-specific features such as noise suppression to reduce the acoustic effects of the hammer and mudmat breakout mitigation systems to ensure that the structure can be retrieved in a variety of soil conditions.

Pre-piling template configurations can vary significantly as the design needs to suit the size of the jackets being installed, the number of piles associated with each jacket, and the installation method used by the vessel selected for the project. There are also options around whether the pre-piling template is standardised for specific applications, or whether the structure is designed to be adjustable for use on multiple projects with different specifications.

2H understands there is a range of options that could be considered in terms of template size, shape, design and functionality and we work with our clients’ specific requirements to develop the most appropriate template design for the project.

Key Services

  • Structural modelling
  • In-place structural analysis
  • Geotechnical design (inc. mudmat sizing)
  • Controls and hydraulics systems design
  • Installation analysis

Project Experience

  • Offshore WindForce – Wikinger – design and supply of a pre-piling template for 70 4-legged jackets
  • DEME – Moray East – design and supply of a pre-piling template for 103 3-legged jackets
  • HMC – Greater Changhua – detailed design of a pre-piling template for 111 3-legged jackets