24B1 Stainless Steel Tube Optical Fiber Unit

As the inventor and owner of the technology for placing optical fibers into stainless steel tubes, GL offers a range of tube sizes and fiber counts for a variety of applications. Each tube is flooded with a thixotropic filling compound and hermetically sealed to protect the enclosed fibers from environmental degradation. This product is sometimes referred to as FIST (Fiber in Steel Tube) or FIMT (Fiber in Metal Tube).

Applications:

OPGW

Umbilical Cables

Downhole Cables for Oil & Gas

Towed Arrays

High Temperature Cables

Hybrid Cables

Sensor Cable

1. Scope

This specification covers general requirements and performance of Stainless Steel Tube Fiber Unit，including optical characteristics and geometrical characteristics

2. Specification

2.1 Steel Tube Specification

Item	Unit	Description
Material		Stainless steel tape
Inner diameter	mm	2.60±0.05mm
Outer diameter	mm	3.00±0.05mm
Filling component		Water repellent, thixotropic jelly
Fiber number		24
Fiber types		G652D
Elongation	%	Min.1.0
Fiber excess length	%	0.5-0.7

2.2. Fiber Specification

The optical fiber is made of high pure silica and germanium doped silica. UV curable acrylate material is applied over fiber cladding as optical fiber primary protective coating. The detail data of optical fiber performance are shown in the following table.

G652D Fiber
Category	Description	Specification
Optical Specifications	Attenuation@1550nm	≤0.22dB/km
Optical Specifications	Attenuation@1310nm	≤0.36dB/km

2.3 Color Identification Of Fiber In the stainless steel tube unit Color code of fiber in the steel tube unit shall be identified referring to the following table:

Typical number of fiber: 24

Remark	Fiber No. & Color
1-12 Without color ring	Blue	Orange	Green	Brown	Grey	White
1-12 Without color ring	Red	Nature	Yellow	Violet	Pink	Aqua
13-24 With S100 color Ring	Blue	Orange	Green	Brown	Grey	White
13-24 With S100 color Ring	Red	Nature	Yellow	VIolet	Pink	Aqua
Remark: If G.652 and G.655 are used synchronously, S.655 should be laid ahead.