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Castrol Transaqua HT2-N

Castrol Transaqua HT2-N

Product description

Castrol Transaqua HT2-N is a water-based hydraulic control fluid specially formulated for use as the control medium in surface and subsea production control system in the Norwegian sector of the North Sea. The fluid incorporates all the features required for operation in a wide range of equipment, and can therefore be used as the operating medium throughout the control system including subsurface safety valve and well control areas.

Castrol Transaqua HT2-N has been developed and qualified under a Quality Management System with ISO 9001:2000 certification and an Environmental Management System with ISO 14001:2004 certification for Research and Development.


- Fully compliant with OSPAR environmental legislation.

- Castrol Transaqua HT2-N has an identical formulation to the field proven Castrol Transaqua HT2 but with the UV tracer and anti-foaming additives removed.

- Essentially identical performance to Castrol Transaqua HT and Castrol Transaqua HT2 with an operating capability up to 180°C (356°F). See Table 1 & Table 2 for detailed physical and performance characteristics.

- Castrol Transaqua HT2-N contains a yellow metal passivator.

- Castrol Transaqua HT2-N is fully compatible and miscible in all proportions with Castrol Transaqua range and most other water-based subsea control fluids.

- As with all glycol based control fluids, Castrol Transaqua HT2-N must never be mixed with control fluids of different base types such as synthetic fluids (e.g. Castrol Brayco Micronic SV/3) or mineral oils (such as the Castrol Hyspin range). Contamination of Castrol Transaqua HT2-N by either of these types of products can seriously affect the product performance.

- Castrol Transaqua HT2-N is resistant to bacterial and fungal growth.

- Castrol Transaqua HT2-N is stable with seawater contamination.

- Castrol Transaqua HT2-N is compatible with a wide range of materials commonly used in subsea control systems, for basic lists see Table 3 & Table 4.

- Proven track record of Castrol Transaqua series chemistry.

- Allows reliable operation of subsea equipment exposed to conventional or HP/HT conditions.

- Compatibility and miscibility properties of Castrol Transaqua HT2-N with other water based control fluids allow for easily managed direct top up and upgrade option programme. For further details contact Castrol Offshore.

- The chemistry of the fluid allows operation at low ambient temperature environments and inhibits hydrate formation.


Castrol Transaqua HT2-N is designed specifically for use in all conventional and high pressure, high temperature applications.

Can operate over a temperature range of -30ºC (-22ºF) to 170ºC (338ºF).

Track record of use in subsea production control systems at tempertures up to 170°C (338°F)

Castrol Transaqua HT2-N is tolerant of the high well temperatures encountered by those parts of the control system located at the well bore.

The low pour point also allows use in areas where low ambient temperatures prevail.

Designed for use within Electro-Hydraulic Multiplex (EH-Mux) or direct hydraulic control systems.

Designed for reliable use throughout the entire production and workover control system, covering Topsides and Subsea applications: both open water and well bore; and Downhole from control of a single SSSV through to complex intelligent well completions.

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