Triple Stranded FIMT (TST)

Undersea Fiber Optic Cable

The Triple Standard Tube is ideal for vertical installation purposes in harsh environments, thriving in ultra-high temperatures of 600°C. Its innovative design prevents gravity from taking a toll on the optical fibers. The helical arrangement of the tubes protects the optical fibers from elongation, maintaining the excess fiber length in the cable.  

The design allows for separation between the optical fiber and potential copper wiring, making it perfect for integration in hybrid lines. The outermost layer is made of highly anti-corrosive steel, giving the undersea fiber optic cable durability in harsh environments. 

undersea fiber optic cable
  • 07-Downhole Downhole optimised
  • 03-Upstream Designed for O&G
  • 24-High Strenght pressure resistant ​


Product abbreviation TST
Cable usage Data Transm. & Sensing
Outer diameter 5.75 mm or 6.35 mm (1/4”)
Dimension of one inner tube 2.35 mm x 0.20 mm
Cost effective steel grade mixing Wide range possible
Outer tube material High anti-corrosive mat.
Approx. Cable weight 76 kg or 123 kg per km
Hydrostatical pressure rating Up to 3 500 bar (calc.)
Maximum continuous length Up to 15 km
Operational temperature range -60°C up to +800°C
Excess Fiber Length (EFL) Exceeds 0.6 %
Perfect usage for Vertical installation

All values, product specifications and other given data are subject to change without notice to improve reliability, function, design or otherwise. Information contained in this data sheet are up-to-date as at the date of issue. As NBG cannot control or anticipate the conditions under which this product may be used, each user should review the information in specific context of the planned use. To the maximum extent permitted by law, NBG will not be responsible for damages of any nature resulting from the use or reliance upon the information contained in this data sheet.

Product overview created by Patrick Weissinger – 21.03.2019

Optical fibers

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Metal tube

undersea fiber optic cable


Thomas Kozlowski

Fiber Optics Solution Specialist.
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