Going beyond: APL’s proven fluid swivel technology reaches a new level

Full-scale testing qualifies APL’s game-changing technology to larger dimensions, high flow volume, more pressure, and higher temperature , ensuring reliability and versatility while reducing risk in harsh environments.

Image of a swivel TQP in a facility, with an NOV employee wearing branded PPE in the forefront
Feb 29, 2024

NOV’s APL group has received technology qualification program (TQP) certification from DNV for its largest swivel. The swivel TQP developed by APL is a game-changer for fluid swivels for oil, gas, e-fuels, and CO2 transfer.

The TQP was developed to meet the increasing demand for larger swivel designs that can withstand higher pressures and temperatures. Large swivel stacks are used for floating production vessels to connect the processing system on the weathervaning vessel with the geostationary subsea installation.

Without the swivel stack, there is no flow of oil or gas on the FPSO. The swivel stack needs to operate 24/7, providing uptime in the harshest weather conditions. The cash flow for the customer starts and stops with the production flow through the swivel.

Sigmund Larsen

Manager Swivel Systems, APL

The qualification program for the swivel TQP was established in cooperation with DNV, an independent verification body. It consisted of a desktop exercise of critical parameters as well as an extensive long-term test program. The test programs were performed with full-scale test swivel units to ensure the testing represented actual project conditions.

A full-scale TQP was completed for one of the largest gas FPSOs ever made, including months of dynamic testing to ensure the technology was fit for purpose. The TQP certification was also used to qualify our swivel technology for a planned FPSO in the sub-arctic region. This huge vessel requires a production swivel solution for up to 560 bar and 120°C (248°F), with a record number of large flow paths and flow capacity.

Prior to this project, APL had qualified its utility swivel for small bore lines for pressures up to 1,380 bar.

“We achieved all our goals, demonstrating that our swivel technology is fit for purpose and can be used for the most demanding future FPSO projects,” said Larsen.

Our swivels provide a qualified, proven, and easy-to-use solution that reduces project risk and improves safety in various applications. The swivel stack can be part of the turret delivery, minimizing external interfaces and keeping them within the NOV scope of work. The APL swivel provides a compact swivel stack design that integrates well with our Submerged Turret Production (STP™) design.

Our STP and Submerged Turret Loading (STL™) technologies are unique, flexible, and cost-effective turret mooring systems for shuttle tankers, storage vessels, or production vessels. APL has delivered more than 23 STP and 21 STL projects in the last 30 years.

Learn more here or contact [email protected].

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