30-Metre Modular Lifting Frame Redefines Scour Protection Installation.
Durham Lifting and Pipeshield International developed a bespoke 30-metre modular lifting frame capable of positioning multiple rows of scour protection mattresses in one controlled lifting operation.
Durham Lifting partnered with Pipeshield International to design, manufacture and test a bespoke 30-metre modular lifting frame for the installation of large scour protection mattress assemblies.
The project required a lifting solution capable of handling several mattress rows simultaneously while operating within demanding site constraints and a tightly controlled installation programme.
Solving a complex offshore lifting challenge
Restrictions on the lifting equipment available at the installation site meant that a conventional frame arrangement would not provide the productivity or coverage required.
Pipeshield therefore required a larger modular frame capable of lifting and positioning several rows of mattresses during each operation. This would allow a greater area of scour protection to be installed in fewer lifts.
Designed through close engineering collaboration
Durham Lifting’s design and fabrication teams worked closely with Pipeshield’s engineers to review the proposed dimensions, lifting configuration and operational requirements.
The frame had to provide the required strength and stability across its full 30-metre span while remaining practical to manufacture, assemble, transport and deploy.
Project-specific configuration
The frame was developed around the mattress dimensions, required lifting points, available crane capacity and installation method.
Modular fabricated structure
The system was manufactured as a modular arrangement to provide the required span while supporting efficient assembly and use.
Proof load tested
The complete lifting arrangement was assembled and tested to verify its performance before mobilisation.
Manufacture and assembly of the 30-metre frame
The completed system represented a significant step forward from the shorter lifting frame previously used for this type of installation. Extending the arrangement to 30 metres created a large but stable lifting platform capable of supporting a longer run of mattresses.
Frame assembly
Proof load testing before mobilisation
The lifting frame was subjected to a controlled proof load test before being released for use. This provided confirmation that the structure, connections and complete lifting arrangement performed as intended under the required test load.
Full frame proof load tested before use
Testing verified the structural performance of the assembled lifting system and provided the required assurance before the equipment was mobilised for the installation.
Supported by Multisec Modular Spreader Beams
Multisec Modular Spreader Beams formed a key part of the lifting arrangement, distributing the applied load across the frame and helping maintain balance throughout the lifting operation.
This load distribution was particularly important because of the increased frame length and the combined weight of the mattress rows being handled.
- Multiple mattress rows handled in one operation
- More even load distribution across the frame
- Fewer separate lifting cycles required
- Reduced repeated handling of mattress assemblies
- Improved installation efficiency
- Greater control across the extended span
Protecting critical subsea infrastructure
Scour protection mattresses are installed around subsea structures to prevent erosion caused by currents, tidal flows and propeller wash. Their effectiveness depends on accurate placement and long-term stability in demanding marine conditions.
Pipeshield carried out Computational Fluid Dynamics analysis supported by previous flume tank testing to assess how the mattress system would perform under combined tidal and propeller forces.
The study confirmed that the mattresses, reinforced using Pipeshield’s N2 edge block technology, could withstand the expected hydrodynamic forces and remain securely positioned.
Fewer lifts, improved efficiency
By increasing the amount of scour protection installed during each lifting cycle, the 30-metre frame helped reduce the total number of lifts required on site.
This supported a faster installation programme, simplified lifting coordination and reduced the time personnel and equipment were exposed to suspended-load operations.
Fewer lifting operations also helped reduce vessel and equipment activity, supporting a more efficient installation with less disturbance to the surrounding marine environment.
“We are thrilled to have collaborated with Pipeshield on this project. Our team’s expertise in lifting solutions, combined with Pipeshield’s industry-leading knowledge, has resulted in a product that sets new standards for the industry.”
Amanda Gardiner, Managing Director, Durham LiftingA new benchmark in modular lifting frame design
The project brought together Durham Lifting’s design, fabrication, testing and lifting expertise with Pipeshield’s specialist knowledge of subsea protection systems.
Through close collaboration, the two teams developed a practical response to a complex installation challenge and delivered a lifting system that improved productivity without compromising stability, control or safety.
The completed 30-metre modular frame demonstrates how bespoke lifting equipment can support safer and more efficient offshore, marine and infrastructure projects.
Learn more about Multisec engineered lifting systems at multisec.com .
Engineered around the lifting challenge.
Durham Lifting and Multisec design, manufacture and test bespoke lifting frames, spreader systems and specialist equipment for offshore, marine and heavy engineering projects.