Harsh environment optical fibers are designed for use at elevated temperatures and pressures in aggressive chemical environments. Typical applications include the oil & gas and geothermal industries, where the fibers are used for real-time downhole temperature and pressure measurements, data transmission, acoustic, seismic and imaging applications. AFL's Verrillon® harsh environment fibers are manufactured with a wide range of polymeric coatings including Polyimide, Silicone, Silicone-PFA and High Temperature Acrylates. In addition, our Verrillon optical fibers are available with a hermetic coating that prevents hydrogen, moisture and acid ingression. The fibers are suitable for operation over a wide range of temperatures from cryogenic up to 500ºC, depending on the coating combination selected. They are also available in a variety of different waveguide designs, including Multimode, Single-mode, Pure Silica Core, Bend-Insensitive and custom profiles.

Carbon Coating Technology: The Ultimate Barrier to Hydrogen Diffusion

AFL’s Verrillon hermetically-sealed optical fibers have been successfully deployed in downhole applications worldwide. The unique composition and method of manufacturing of our carbon coating make it the most reliable barrier against hydrogen for temperatures exceeding 150°C. Our online monitoring system ensures the integrity of the carbon layer throughout the entire length of the fiber. Additionally our state-of-the-art hydrogen testing facility simulates well conditions and provides performance predictions for our customers.

Glass Technology: The Ultimate Resistance to Hydrogen Darkening at High Temperatures

With the development of emerging monitoring technologies such as temperature, pressure, strain, flow, seismic and acoustic, the need for optical fibers and cables that withstand high temperatures (300ºC or higher) and high partial pressures of hydrogen in downhole environments increased dramatically.

Our approach to the high temperature, high hydrogen partial pressures is to modify the glass composition of the optical fiber core to make it inherently resistant to hydrogen attack. This research culminated in the VHM5000 Series of fibers that are completely immune to hydrogen-induced loss. The Verrillon® VHM5000 technology is the result of a uniquely optimized glass design that is exclusively available from AFL.

What makes Verrillon® fiber so reliable?

• Best-in-class hermetic coating ensures that the fiber is highly resistant to molecular hydrogen, water and corrosive chemicals
• Proprietary glass chemistry designs enhance hydrogen resistance and reduce darkening showing negligible loss after extended exposure to hydrogen
• The industry’s broadest range of specialized coatings allow fibers to maintain their reliability from cryogenic temperatures up to 500°C
• Quality control and product certification using proprietary online real-time monitoring technique ensure uniform fiber hermeticity throughout continuous, proof-tested lengths exceeding 20 kilometers
• Large variety of waveguide designs include multimode graded and step-index, single-mode, pure silica core and custom index profiles