ADSS (All-Dielectric Self-Supporting) cable is an all-dielectric self-supporting optical cable specially designed for power systems. It can be safely and reliably erected on high-voltage transmission lines to achieve communication and data transmission in power systems. In order to ensure the stability and safety of ADSS optical cables under complex electric field environments, wind loads, temperature changes and other factors, a series of special fittings need to be used. The following is an introduction to the main types of ADSS optical cable fittings and their functions:
1. Anti-halation
Purpose: On transmission lines with voltage levels of 110KV and above, when the ADSS optical cable enters a higher space potential, it may be affected by corona discharge, which will not only cause damage to the performance of the optical cable, but may also cause electromagnetic interference. The anti-halo ring is installed at the contact point between the optical cable and the hardware to protect the optical cable from corona damage by improving the electric field distribution and reducing the occurrence of corona discharge.
2. Tension-resistant hardware
Purpose: Tension-resistant hardware is mainly used to withstand the tension generated during the erection and operation of ADSS optical cables, and to safely and evenly transfer it to the tower or support structure. Tension-resistant hardware is usually installed at terminal towers, tension-resistant towers and optical cable connection towers to ensure that the optical cable remains stable under large-span and high-load conditions and to prevent damage or breakage of the optical cable caused by excessive tension.
3. Hanging hardware
Purpose: Suspension fittings are used to hang ADSS optical cables on linear towers so that the optical cables maintain a certain sag under normal working conditions and can swing flexibly under wind load. The hanging fittings fix the optical cable through the inner and outer twisted wire structure, and at the same time provide appropriate buffering to reduce the stress concentration on the optical cable caused by wind vibration or temperature changes.
4. Fasteners and connecting hardware
Purpose: These fittings include but are not limited to anchoring clamps, wedge clamps, U-shaped hanging rings, PD-type hanging plates, etc. They are responsible for reliably connecting ADSS optical cables to fittings, fittings to towers or other supporting structures. Fasteners and connecting hardware ensure the stability of optical cable installation and prevent loosening or falling off due to vibration, wind swing and other dynamic loads.
5. Pre-twisted wire
Purpose: Pre-twisted wire is a common component in ADSS fittings. It is used to wrap optical cables, provide uniform grip, and protect the outer sheath of optical cables from excessive stretching and wear. The pre-twisted wire is divided into inner twisted wire and outer twisted wire. The inner twisted wire is in direct contact with the optical cable, which reduces uneven stress on the optical cable by increasing the contact area and dispersing stress. The outer twisted wire is connected to the tower through connecting hardware such as an insert ring. , bear the line load.
6. Anti-corrosion treatment
Purpose: In order to ensure the long-term service of the hardware in harsh outdoor environments, anti-corrosion treatment, such as hot-dip galvanizing, is usually performed to improve the corrosion resistance of the hardware and extend its service life.
7. Technical parameters
Important indicators: The selection of ADSS optical cable fittings needs to consider parameters such as the ultimate tensile strength, operating span, outer diameter, maximum allowable tension, daily operating tension, and lateral pressure resistance strength of the optical cable. The hardware should be able to provide sufficient grip strength (generally required to be no less than 95% of the ultimate tensile strength of the optical cable) and adapt to the specific twisting direction of the optical cable.
8. Ordering and selection
Note: When ordering ADSS Cable Fittings Manufacturer, you need to provide the specific parameters of the optical cable in order to match the appropriate fitting model. For different application scenarios (such as urban 10kV distribution network), there may be specially designed hardware, such as tension clamps with a grip strength of 15kN. Such hardware often has a simplified structure, is easy to install, and helps reduce project costs.
To sum up, ADSS optical cable fittings are a series of accessories specially designed to support, fix, protect and connect ADSS optical cables. They work together to ensure the safe and efficient operation of optical cables in power transmission line environments. The selection and correct use of standard fittings is crucial to ensuring the long-term stability and reliability of the optical cable system.