Insights

Innovative Directions for Jacket and Pin Pile Installation

As the industry continues to evolve, exploring innovative design directions is essential to address the challenges posed by transporting and installing larger turbines and foundations. Achieving optimal installation methods for these larger pin piles requires a holistic approach considering project-specific parameters, vessel capabilities, and installation efficiency. Key factors include location, water depth, soil conditions, and environmental factors. Additionally, the capabilities and availability of installation vessels, along with operational costs, are crucial considerations.

Innovation is essential for the continued growth and success of the offshore wind industry. By exploring design alternatives that consider project-specific factors, the offshore wind industry can overcome the challenges posed by larger turbines and deeper water installations. These potential solutions not only improve installation efficiency and workability but also contribute to the ambitious goals set by the 2030 Paris Agreement. Here are three innovative solutions by TWD that could provide directions to tackle some of the challenges faced by offshore wind developers and contractors, focusing on the installation of jackets:

Rotating Pre-Piling Template

One potential innovation is the development of a rotating pre-piling template. This lightweight alternative reduces the required crane capacity and maximizes fleet availability. The design features a 360-degree rotating top layer reducing overall mass, retractable pile supports for potential hammer pass-through, and increased pile support spacing, via an increased height of the template. The wider base of the mud mats enhances global stability, resulting in a reduction of required template weight and improved efficiency of the installation equipment. This approach addresses the challenge of handling longer pin piles in deeper waters, particularly in regions like APAC, where soil conditions can be challenging and jacket foundations are favorable.

The rotating pre-piling template leverages a long distance between the top and bottom supports while maintaining a lightweight structure. This design ensures that the template can handle the increased forces exerted by larger pin piles and deeper water installations. The 360-degree rotating top layer allows for precise alignment and stability during installation, which is crucial for maintaining the structural integrity of the foundation. Additionally, the retractable pile supports enable the hammer to pass through easily, facilitating a smoother installation process.

One of the key advantages of this design direction is the reduced crane capacity required for installation. By keeping the overall structure lightweight, the rotating pre-piling template allows for the use of a wider range of jack-up vessels, maximizing fleet availability and reducing costs. The increased pile support spacing and enhanced stability provided by the mud mat positioning further contribute to the efficiency and reliability of the installation process.

Integrated Scour Protection Deployment System

Another promising approach is the integration of a scour protection deployment system into the pre-piling template. Scour, the removal of local sediment due to a structure obstructing the flow, can negatively impact the structural strength of foundations. Traditional scour protection methods involve multiple layers of rock, which can be costly, and deployment requires specialized vessels. An integrated scour protection system eliminates the need for a dedicated scour installation campaign, reducing costs and improving efficiency. The scour protection consists of a ballasted geotextile layer that prevents soil washout and remains stable even with changing seabed levels.

This integrated system addresses the challenge of preventing soil erosion around foundation piles. Scour can create holes around the piles, weakening the foundation and compromising the stability of the structure. Traditional methods of scour protection involve the installation of a filter layer and an armor layer, which can be time-consuming and require additional lifts and specialized vessels.

By integrating a permanent scour protection system into the pre-piling template’s mud mats, simultaneous installation of scour protection and foundations becomes possible. The system remains in place after the template is removed. This approach eliminates the need for a separate scour installation campaign, reducing the overall project timeline and costs. The ballasted geotextile layer used in the scour protection system is relatively impermeable, preventing soil washout while remaining stable and flexible enough to adapt to changing seabed levels. This flexibility ensures that the scour protection system remains effective even in dynamic marine environments.

Single-Layer Pre-Piling Template

A third direction involves the use of a single-layer pre-piling template designed for crane-less jack-up vessels. This innovative solution eliminates the need for state-of-the-art offshore installation assets. The single-layer pre-piling template is deployed from below a jack-up vessel, allowing for the installation of pin piles with widely available assets such. This method prioritizes cost-efficiency over high workability, making it a commercially attractive option, especially in the APAC region. The streamlined process ensures maximum method reliability and optimal performance, even with limited template height to avoid port entry problems.

The single-layer pre-piling template is designed to be lightweight and easy to deploy, making it an ideal solution for projects with limited access to advanced offshore installation assets. By utilizing jack-up vessels, this direction reduces the reliance on expensive and specialized equipment, lowering overall project costs. The template is suspended and lowered by winches, with the sleeves stabbed into the soil to provide lateral resistance against environmental conditions. Vertical stability is maintained by both the soil and constant tension on the winches.

This method ensures that the pin piles are installed accurately and efficiently, even in challenging conditions. The use of widely available assets such as sheer leg cranes and barges further enhances the cost-efficiency of the installation process. By prioritizing cost-efficiency over high workability, the single-layer pre-piling template offers a commercially attractive solution for offshore wind projects, particularly in regions with limited access to advanced installation assets.

Download TWD’s Jacket Track Record

By collaborating closely with our clients and fabricators, TWD delivers innovative foundation installation equipment and smart methods tailored to the specific needs of each project. Our Jacket Foundation Track Record highlights TWD’s contributions to the successful installation of jacket foundations for offshore wind campaigns worldwide. Are you curious to learn more about tailored equipment design and innovative installation methods for jacket foundations? Download TWD’s Jacket Foundation T&I Track Record here.