NOV to supply its first actively heated flexible pipe system

This certified heated flexible pipe enhances flow assurance, efficiency, and operational flexibility.

Current is passed through the stainless steel carcass (high resistance = heating) and returned in the carbon steel tensile armor wires (low resistance = low to no heating), ensuring that ~95% of the heat is dispersed through the carcass. Closed loop system – no additional layers are introduced, and everything happens internally in the pipe and end fitting. Hence, corrosion assumptions still apply in accordance with standard industry practice for flexible pipes.
May 01, 2024

In March 2024, NOV’s Subsea Production Systems (SPS) business unit signed a contract with an undisclosed customer to deliver an actively heated flexible pipe system for a gas project in the Black Sea. NOV will supply its first active heated pipe system in 2025, introducing a proprietary technology solution of electrically heating the bore of the pipe through the resistance of the pipe’s inner carcass layer.

NOV’s heated pipe technology is designed to tackle wax and hydrate issues in subsea energy operations. This innovative method eliminates traditional, costly, time-sensitive, and potentially ineffective mitigation techniques - and offers a more compact footprint compared to other heating technologies.

The heated pipe system uses the properties of a standard flexible pipe, bringing a range of flow assurance benefits to operations. It aims to increase operational flexibility, reduce costs, prevent or remove hydrate plugs, and facilitate transporting viscous fluids over long distances.

This certified technology comes with standard power components, leading to lower installation, lifetime, and operational costs than competing technologies. The electrical current simply passes through the inner stainless steel carcass layer and returns via the metallic armor layers.

The original idea for this technology came from our engineers, who realized that conventional unbonded flexible pipe in its nature is also a coaxial cable, with its mixture of metallic and polymeric layers. We spent several years in the laboratory and on detailing the design of end connectors to create a robust and fully certified solution, ready for deployment. Dissipating the heat directly in the bore, like your electric kitchen kettle, brings maximum energy efficiency.

Jan Rytter

R&D Director, NOV’s SPS

This achievement by our New Product Development and Commercial teams represents a significant advancement in addressing flow assurance challenges, specifically in eliminating wax deposits and hydrate formations within a flexible pipe riser. Notably, our solution operates 50% more efficiently than traditional methods, delivering targeted heating only when needed, without requiring additional insulation or modifications to the flexible pipe design. Furthermore, it empowers the customer with comprehensive monitoring and control capabilities for both regular operations and shutdowns.

Torbjörn Weywadt Nilsen

Vice President Sales, NOV’s SPS

Learn more here.