Fiber optic cable laying using air blowing method

Fiber optic cable blowing uses high-speed airflow combined with mechanical pushing to efficiently install cables through pre-installed ducts or conduits.

Overview of the Blowing Method

Fiber optic cable blowing, also called air-assisted installation or jetting, involves pushing the cable into a conduit while injecting compressed air behind it. The air flow helps the cable "float" inside the duct, reducing friction and minimizing the risk of damage or jams. This method is preferred over traditional pulling for long or complex duct routes because it allows rapid deployment and reduces labor requirements .

Key Components

• Blowing Head: Attaches to the cable and seals it to allow air pressure to push the cable through the conduit .
• Air Compressor: Provides the high-pressure airflow needed to move the cable. Compressors must be powerful enough to handle long distances and bends in the duct. For example, the MOBILAIR M17 delivers up to 15 bars of pressure and 1.6 m³ of air per minute at 7 bar .
• Duct/Conduit: The pre-installed pipe through which the cable is blown. The conduit should be slightly larger than the cable to reduce friction and allow smooth installation .
• Cable Carrier or Parachute (optional): Sometimes used to guide the cable and maintain slack during installation .

Installation Procedure

1. Prepare the Duct: Ensure it is free of obstructions and pressurized to check integrity .
2. Attach the Blowing Head: Connect the cable to the blowing head, ensuring a tight seal.
3. Initial Push: Mechanically push the cable a few hundred meters into the duct using a tractor or traction rollers .
4. Inject Compressed Air: Begin blowing air behind the cable to float it through the duct. The air reduces contact with the duct walls, minimizing friction and potential damage .
5. Monitor Progress: Track cable length and ensure smooth movement. Adjust air pressure or pushing force as needed.
6. Completion: Once the cable reaches the endpoint, disconnect the blowing head and secure the cable.

Advantages

• Minimizes cable damage and stress.
• Reduces risk of jams in bends or long ducts.
• Faster installation over long distances.
• Can handle microduct and standard fiber optic cables, including armored and unarmored types .

Considerations

• Cable Flexibility: Stiffer cables perform better in straight ducts, while flexible cables navigate bends more easily .
• Bend Radius: Respect the minimum bend radius to avoid kinking or damage.
• Distance Limitations: Extremely long ducts may require multiple compressors or intermediate access points.
• Lubrication: Low-friction cables or blowing lubricants can improve performance . Fiber optic cable blowing is a highly efficient method for modern network installations, especially in urban or long-distance deployments, providing speed, safety, and reduced labor costs compared to traditional pulling methods .