As offshore crane operations extend into deeper waters and run for longer durations, lifting systems increasingly shape how work is carried out on deck. What was once an occasional crane lift becomes a routine condition, and the characteristics of the crane rope begin to influence where people stand, how tasks are sequenced and how much of the deck remains accessible during operations. Against this backdrop, a new class of synthetic crane rope systems, such as TechIce with Technora fibres, has begun to change how operators plan and execute lifting on deck.

For Stabbert Maritime, a Seattle-based operator of offshore support vessels, this shift became clear during the refit of its multipurpose vessel Ocean Guardian. The vessel was configured for continuous deepwater crane operations to depths of 6,000 metres, supporting subsea, survey and scientific work, with crane lifts expected to occur almost daily rather than intermittently.

Steel wire rope, long treated as the standard for offshore cranes, began to dictate operational boundaries. Its behaviour under load constrained crew positioning and deck access, with permanent exclusion zones forcing routine tasks to be organised around separation from the crane line. With lifts now occurring more frequently, the rope itself began to influence how crane work was carried out, not just how it was controlled.

The challenge

Three steel-related conditions defined how crews could work safely around crane systems during continuous operations.

Challenge 1: Snap-back limiting crane deck use
“Snap-back is treated as an assumed condition,” explains Daniel Stabbert, CTO of Stabbert Maritime. “Crews are trained to plan around it, work around it and keep clear of the line whenever it is under load. When you are operating in water depths beyond 4,000 metres, there’s no margin for improvisation around the line.” As a result, crane deck layout and task sequencing are driven by required separation from the line rather than by operational workflow.

Challenge 2: Lubrication affecting crane deck conditions
Steel wire requires lubrication to manage wear under load. During crane operations, lubricant migrates from the rope onto drums, sheaves and surrounding deck surfaces, necessitating ongoing cleaning and containment measures. As lift cycles accumulate, crane deck conditions require increased housekeeping attention.

Challenge 3: Line mass limiting crane handling proximity
At deepwater lengths, steel wire carries substantial self-weight. During spooling, empty-hook recovery and load transitions, this mass increases the energy present in the crane system and the consequences of uncontrolled movement. As a result, routine handling requires greater separation from the line and limits manual interaction in its vicinity.

In response, Stabbert Maritime began looking for an alternative. Incremental adjustments to steel-based crane systems were assessed but discounted, as scaling capacity for continuous deepwater crane work would have required larger winches, increased deck footprint and tighter operating margins, while introducing risk of schedule loss and commissioning delays. As Daniel Stabbert explains, “We weren’t trying to chase headline performance. We needed a system that behaved predictably every day instead of one that people had to keep compensating for.”

The alternative was TechIce, a hybrid synthetic hoisting rope manufactured by Hampidjan and incorporating Technora aramid fibres from Teijin Aramid. It supports continuous deepwater duty by delivering predictable fatigue behaviour, thermal stability under cyclic bending and handling characteristics that reduce crew exposure during routine crane operations.

The solution

The replacement crane system was selected using a deliberately cautious acceptance approach shaped by the safety and operational consequences of failure. Rather than relying on tighter procedures or theoretical performance gains, Stabbert Maritime evaluated alternatives based on how they behaved during routine deepwater crane operations under representative conditions.

System architecture

To address this operational challenge, Stabbert Maritime turned to Parkburn, an engineering firm specialising in deepwater lifting systems designed for continuous duty.

Parkburn designed the deepwater capstan winch that formed the mechanical core of the crane system. The architecture separates traction from storage and delivers the required lift capability within the vessel’s existing power envelope and deck footprint, without requiring changes to foundations or auxiliary systems.

The fully electric winch is configured for continuous operation with synthetic rope. By limiting stored energy in the crane system and avoiding assumptions associated with steel wire stiffness and mass, the winch reduces the extent to which crane activity influences deck access during operations.

Sam Bull, Business Consultant at Parkburn, explains that the design reflects a different set of priorities than traditional steel-based crane systems. “Designing for continuous duty places emphasis on consistent behaviour over time, rather than on peak performance in isolated lifts,” he states.

He adds that rope performance cannot be understood in isolation: “Fibre and rope companies spend most of their time proving their products outperform competitors in isolation, rather than understanding how they behave within the actual deployment and recovery system. Real performance is governed by the entire operating environment.”

This systems-based perspective set the context for independent testing later conducted by NORCE Research.

Independent verification

To better understand rope behaviour under system-level conditions relevant to deepwater crane operations, Hampidjan commissioned independent cyclic bend-over-sheave testing through NORCE Research. The testing was conducted at the Mechatronics Innovation Lab using repeated cyclic bending at a defined speed and elevated ambient temperature, without external cooling, to represent sustained operational loading.

Ellen Nordgård-Hansen, Senior Researcher at NORCE Research, explains: “Cyclic bending and heat are the primary drivers of hoisting rope degradation in practice.”

The outcome

For crane crews, the difference was immediately noticeable. Spooling and empty-hook recovery settled into routine practice, and line behaviour remained consistent as loads changed. During extended periods of active heave compensation, the rope did not generate the heat or deck contamination typically associated with prolonged crane operations using steel wire.

That consistency influenced how work was organised on deck. With no lubricant transferring onto surfaces and lower line mass to manage, the lifting area did not require repeated clearance during operations. Tasks that would normally be delayed during crane lifts were carried out in parallel.

When the system stops dictating the work

The experience on Ocean Guardian shows that deepwater crane capability does not inherently require lifting systems to dominate deck organisation. When systems are selected based on behaviour during routine use, crane operations can be integrated without continually reshaping how work is carried out.

The independent cyclic bend-over-sheave test data behind this system transition is available at a dedicated platform— including fatigue progression, thermal response and strain behavior under sustained loading conditions.