300°C SST Fiber Optic Cable - Fiber In Metal Tube (FIMT) - Communication / Sensing Optical Cable

Aliases: 300°C Corrosion-Resistant Alloy 825 Fiber Cable, 300°C 316L Marine-Grade High-Temp Fiber Unit, 300°C Acid-Proof SST Sensing Cable, Premium Sensing Unit for 300°C DTS, 300°C Vibration-Sensitive Metal-Clad Fiber, Borehole 300°C Armor-Fiber, Hermetic Seamless 300°C Optical Unit, 300°C Hydrogen-Tough SST Fiber Cable, 300°C Double-Barrier High-Temp Fiber

1. Product Overview of OFSCN® 300°C High-Temperature Fiber Optic Cable

The OFSCN® 300°C High-Temperature Fiber Optic Cable is a premium sensing-grade cable engineered for ultra-high temperature and harsh industrial environments. The cable features a single-layer seamless metal tube encapsulation housing specialized OFSCN® 300°C Polyimide Coated Optical Fibers (available in SM and MM). Utilizing 316L Stainless Steel as the standard jacket (with Alloy 825 as an option), this cable provides superior hydrogen shielding and mechanical protection. It is the most reliable sensing unit for Distributed Fiber Optic Sensing (DFOS) systems (DTS, DAS, DSS) operating up to 300℃.

2. Technical Parameters of OFSCN® 300°C High-Temperature Fiber Optic Cable

Key Parameters	Spec A (2.0mm)	Spec B (3.0mm)	Custom Options
Outer Diameter (OD)	2.0 mm	3.0 mm	1/8" (3.175mm) / 1/16" (1.58mm)
Wall Thickness	0.2 mm	0.3 mm	Tailored to requirements
Tube Material	316L SS (Default) / Alloy 825	316L SS (Default) / Alloy 825	316L / 825 / Hastelloy, etc.
Theoretical Weight (316L)	~9.05 kg/km	~20.36 kg/km	Varies by material density
Tensile Strength	> 550 N	> 1200 N	Excellent creep resistance
Crush Resistance	> 100 MPa	> 100 MPa	High-pressure rated
Operating Temp.	-200 to 300℃	-200 to 300℃	Long-term stability
Min. Order Qty (MOQ)	500 Meters	500 Meters	-

3. Internal Fiber Configuration of OFSCN® 300°C High-Temperature Fiber Optic Cable

The cable can be configured with one or more OFSCN® 300°C grade PI-coated fibers:

• Fiber Types:

Single-mode: OFSCN® 300℃ SM Polyimide Optical Fiber

Multi-mode: OFSCN® 300℃ MM Polyimide Optical Fiber

• Coating Material: Enhanced High-Temperature Polyimide (PI), approx. 15μm thickness.
• Connectivity: Available with pre-terminated FC/APC or FC/PC high-temperature connectors, or standard fusion splicing.

4. DFOS Compatibility Analysis (300℃ Optimized) of OFSCN® 300°C High-Temperature Fiber Optic Cable

This product is specifically optimized for distributed sensing applications in 300℃ environments:

4.1 Distributed Temperature Sensing (DTS) — Raman Scattering

• Key Advantage: The 316L seamless tube provides an exceptional barrier against hydrogen darkening, preventing signal attenuation caused by hydrogen ingress at high temperatures. This ensures long-term accuracy and stability of DTS systems at 300℃.
• Thermal Response: The thin-walled metal design ensures second-level response to temperature fluctuations in 300°C environments.

4.2 Distributed Temp. & Strain Sensing (DTSS) — Brillouin Scattering

• Pressure Protection: In deep-well or high-pressure reactors, the 316L tube resists pressures over 100 MPa, protecting the internal SM fiber from micro-bending losses.
• Strain/Temp Separation: Paired with 300°C PI fiber, it enables precise long-distance deformation or temperature monitoring under extreme thermal stress.

4.3 Distributed Acoustic/Vibration Sensing (DAS/DVS) — Rayleigh Scattering

• Acoustic Conduction: The high rigidity of 316L or Alloy 825, combined with the ultra-thin 15μm PI coating, allows acoustic vibrations to reach the fiber with minimal damping. This is ideal for high-temperature pipeline leak detection or seismic data acquisition.

5. Sensing Technology Matching Matrix of OFSCN® 300°C High-Temperature Fiber Optic Cable

Sensing Tech	Principle	Recommended Fiber	Key Advantages
DTS	Raman Scattering	300℃ MM	Hydrogen resistance & rapid thermal response; Ideal for 300℃ industrial furnaces.
DAS / DVS	Rayleigh Scattering	300℃ SM	High rigidity & low acoustic damping; Ideal for high-temp pipeline vibration.
BOTDA / R	Brillouin Scattering	300℃ SM	Robust mechanical protection; Suitable for sensing under extreme pressure.
F-P / FBG	Wavelength Shift	300℃ SM	High-temp grating writing; Alloy 825 provides extreme corrosion protection.