ENVIROSOL USF04 is a low viscosity environmental oil based umbilical storage fluid for both thermoplastic and steel tube umbilicals, with a wide operational temperature range between -40 °C to 200 °C / 392 °F.

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Did you know...

Using USF04 can offer significant project savings in many instances by negating the need to flush umbilical lines when using SURF Chemicals.

Product Overview

ENVIROSOL USF 04 is an environmental oil based umbilical storage fluid offering maximum mixed fluid stability towards wellbore chemicals in aggressive HPHT (and less demanding) environments.

ENVIROSOL USF04 can offer significant cost savings during umbilical commissioning due to its superior compatibility with SURF (Subsea, Umbilical, Riser, Flowline) chemicals and can negate the need for Topside or Subsea intervention for the interface requirements to First Oil or for Future Extensions.

ENVIROSOL USF04 has undergone chemical compatibility testing far beyond any previous industry standards for USF’s, including a wide range of temperatures and mix ratios and extended service related testing. Testing includes blockage flow tests and HPHT testing of mixtures to ensure stability in extreme situations and minimisation of potential issues in service.

ENVIROSOL USF 04 is designed to have the lowest viscosity profile possible for an ‘oil based’ product with the key physical properties outlined below.

ENVIROSOL USF04 is environmentally acceptable for use in OSPARCOM countries, boasting a 'Yellow' status (Norway) an OCNS Class E (UK) and meets GOM toxicity requirements.

Key properties

Significant Commissioning and Project Savings

Can Negate Topside or Subsea Intervention

Low Viscosity Profile for an Oil Based Product

Superior Compatibility with SURF Chemicals

Extensive Mixed Fluid Compatibility Database

Yellow / OCNS Class E for Discharge

Meets GOM Toxicity Requirements

Excellent Metal and Elastomer Compatibility

Typical physical properties

Note these properties are typical for the product but do not constitute a specification.



Pour Point (C)

< -40 C

Upper Temperature (C)

200 C

Density @ 5 C

0.827 gcm

Viscosity @ 5 C

10.5 cst

Viscosity @ 40 C

3.9 cst

Water Solubility


Product Support

Office based technical support system

Technical support during the fluid selection process and ongoing in the field is a crucial element of our service and we are here to support you and help you make informed decisions on our products.

Product Range

We offer a wide range of environmental oil based subsea production control fluids, subsea actuator fluids and umbilical storage fluids.

We offer a wide range of environmental oil based hydraulic fluids for both topside and subsea applications to suit all budgets and applications.

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