NEPTUNE™ Advanced Subsea Flow Assurance Insulation System

The next wave in flow assurance technology

With global demand for oil increasing but reserves becoming more difficult to reach, Dow Oil & Gas is continually developing innovative solutions to help producers access this valuable resource from more extreme environments – safely and responsibly.

Continuing the strong legacy of the HYPERLAST™ line of flow assurance solutions – used for more than 25 years in over 500 successful projects worldwide – comes the next wave in flow assurance technology: NEPTUNE™ Advanced Subsea Flow Assurance Insulation System.


A breakthrough in response to an unmet market need

The widest use temperature range of any wet insulation system on the market

The NEPTUNE™ Advanced Subsea Flow Assurance Insulation System was designed in response to direct requests from offshore operators for a high-temperature flow assurance insulation system. The result of a multi-million-dollar and multi-year R&D effort led by Dow, the NEPTUNE™ System is engineered to deliver proven performance at operating temperatures from -40°C to 160°C.


Features and Benefits

From the North Sea to the Gulf of Mexico ...
The responsible choice

Complete, End-to-End System

  • Can be used in applications from the wellhead to delivery point (line pipe, field joints and subsea architecture)
  • Simplifies processing across a wide range of environmental conditions using standard industry equipment

Dual-Layer Composition

  • One anti-corrosion coating and one solid, homogenous insulation layer
  • NEPTUNE™ FBE Anti-Corrosion Coating – fusion-bonded epoxy based on patented Dow resin technology
  • NEPTUNE™ Flow Assurance Insulation Coating – proprietary hybrid polyether thermoset

Exceptional Thermal Performance

  • Excellent thermal insulator
  • On-pipe K-factor of 0.152 W m-1 K-1 (SST at 160 °C & 300 bar)
  • High specific heat of 1.2 – 1.7 J g-1K-1 (0 – 160 °C)

Performs Across Temperature Extremes

  • The widest use temperature range of any wet insulation on the market
  • Excellent physical properties enable installation at temperatures to -40°C
  • Excellent hydrolytic and thermal stability for service temperatures to at least 160°C

In-Service Durability

  • Passed the Simulated Service Test at 160°C, including three planned system shutdowns, showing excellent stability in all conditions
  • Passed both the Flexural Fatigue Test and the Thermal Shock Test with no signs of damage or delamination
  • Incompressible to at least 400 bar pressure
See results from rigorous testing

Features and Benefits

Rigorously tested and ready to meet your flow assurance needs

To ensure the NEPTUNE™ System is ready to meet customers’ stringent design requirements, it was subjected to an extensive battery of small- and production-scale testing, performed by Dow and some of the industry’s most respected applicators. Select results are given here. For additional details,download the brochure, watch the video or contact us.

Typical Properties of NEPTUNE™
Advanced Subsea Flow Assurance Insulation System
Installation method Reel, S-lay, J-lay
Depth rating, m At least 4,000
Subsea service temperature, °C -40 to +160
Thermal conductivity under SST conditions(1),W m-1k-1 0.152
Density (ASTM D792, 23°C), g cc-1 1.1
Heat capacity (ASTM E1269, 0 to 160°C), J g-1 k-1 1.2 to 1.7
(1)160ºC at 300 bar for 28 days



NEPTUNE™ Overview
NEPTUNE™ Overview Video
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For Editorial Information

Allison Bushre
Dow Oil & Gas
+1 281 966 4822
Christina Atkinson
Gibbs & Soell Public Relations
+ 1 212 697 2600, ext 1209
NEPTUNE System Illustration

NEPTUNE™ System Illustration
The NEPTUNE™ System features a dual-layer composition: NEPTUNE FBE Anti-Corrosion Coating (thin blue layer), a fusion-bonded epoxy based on patented Dow resin technology, and NEPTUNE Flow Assurance Insulation Coating (thicker yellow layer), a proprietary hybrid polyether thermoset.
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Hydrolic Stability Test

Hydrolytic Stability Test
In the Hydrolytic Stability Test, samples of NEPTUNE™ Insulation Coating were aged at 160°C and a hydrostatic pressure of 300 bar for 3,000 hours (~18 weeks) in an autoclave. The tensile strength of the aged insulation was then compared to non-aged samples, indicating the system's property retention and overall polymer integrity.
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Flexual Fatigue Test

Flexural Fatigue Test
The Flexural Fatigue Test demonstrated the flexibility of the NEPTUNE™ System and its resilience to vibrations that may be experienced during production.
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Thermal Shock Test

Thermal Shock Test
The Thermal Shock Test demonstrated overall mechanical integrity of the NEPTUNE™ System under temperature variations that may be experienced during start-up.
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Simulated Service Test

Simulated Service Test
In the Simulated Service Test, a coated pipe was subjected to hydrostatic pressure of 300 bar, water temperature of 4°C and service temperature of 160°C for 28 days, with three planned system shutdowns. This determined the overall heat transfer coefficient of the NEPTUNE™ System and validated its consistency in cool-down throughout the aging cycle.
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Tensile Test

Tensile Test
The Tensile Test demonstrated the NEPTUNE™ Insulation Coating's strength, flexibility and ability to withstand the rigorous lay process.
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Compressive Strength Test

Compressive Strength Test
The Compressive Strength Test demonstrated the NEPTUNE™ Insulation Coating's resiliency during the coating process, transport and final lay on the ocean floor.
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About Us

Bringing chemistry to the oilfield since the 1920s

Dow Oil & Gas is a business unit of The Dow Chemical Company and its consolidated subsidiaries. That means that you not only get the benefit of in-depth industry knowledge from Dow Oil & Gas, you also get the backing of Dow’s long history as a global chemistry leader and R&D powerhouse.

Dow’s problem-solving process also brings a unique merger of chemistry and engineering experience for a more comprehensive understanding and solution to your challenges. Our innovative, customized and tested solutions are designed to meet the ever-changing needs of the oil and gas industry. In addition, we offer exceptional technical service.

With proven, reliable solutions to maximize the potential of your offshore assets – from exploration to production and processing – we want to be your total solutions provider for flow assurance and other subsea applications. Contact us to discuss how we can help.

Learn more about Dow’s comprehensive solutions and services for applications throughout the oil and gas value chain at

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