The technical requirements for overhanging are mainly:
(1) The sum of the double suspension angles of the single suspension fixture shall not be less than 300, and the sum of the double suspension angles of the double suspension fixture shall not be less than 600:
(2) The suspension fixture should meet the requirements of vertical load and clamping strength, and the clamping strength is generally 15% of the rated tensile force of the optical cable:
(3) The synthetic rubber parts in the suspension fixture should have good anti-aging properties, as well as the ability to prevent ozone, ultraviolet rays and air pollution;
(4) When the horizontal unbalanced load exceeds the design value, the clamp should slide.
Among them, the single overhang structure is the most commonly used structure for power lines. For suspensions or supports with high pressure drop, line spacing greater than 800 meters or line angle greater than 300, a double suspension structure is usually used.
Also, pre-twisted fittings are a good solution for circuit protection compared to traditional crimp fittings. If the adjacent gear distances increase the load and cause unbalanced force values for some reason, traditional crimp fittings can cause the tower to tip over, the sliding properties of the pre-twisted metal fittings can ensure the safety and line of the tower .
Other Pre-Twisted Accessories
As the advantages of pre-twisted fittings continue to be explored, their use in power lines is increasing. Whereas conventional bolt-type joints slip under long-term breeze vibrations, pre-twisted joints do not. Therefore, pre-twist fittings have been widely used in anti-vibration hammers and anti-corona rings. on power cord assemblies such as spacers. However, the pre-twisted wires of these accessories are tailored to the specific line, and the pre-twisted wires of different lines cannot be replaced with each other.
Pre-twisted connecting strip or repair strip
Often, for some reason, wires or ground wires (including OPGWs) break the stranded wire during operation. The traditional approach is to reconnect the chain near the chain. Since the OPGW has headroom when erected, in most cases wiring can be routed by releasing the remaining fiber optic cable to form a splice in the nearest tension tower, or simply replacing the fiber optic cable between the two towers. If pre-stranded or repaired strips are installed on the strands, the tensile strength will be at or above 95% of normal tensile strength.
Cable accessories
Cable accessories are mainly used to secure the Ramata to prevent the tower from falling due to unbalanced forces. A pull wire fitting is actually a sheet metal fitting that holds both ends of the wire with pre-twisted metal fittings. Because the ends of the tension clips are looped, it is easy to thread through ground anchors or hoop bolts, etc., and the clip wire is very nice on the pull wire.
Compared with the traditional optical cable joint, the pre-twisted optical cable joint has the advantages of high safety, strong applicability, good anti-theft performance, low investment, simple process and flexible operation. Practice has proved that pre-twisted optical cable accessories have the potential of application and promotion.
Pre-twisted fittings for insulated wires At present, in the construction of low-voltage overhead insulated wires, the insulation on the compression tower must be flattened, then crimped with wire clips, and then hung on the pole through insulators.
The original insulated wire was destroyed. Adding insulators is not only time-consuming and expensive, but also inefficient, and the tower can leak in rainy and foggy weather. These problems can be easily solved if the insulated wires are installed directly using pre-tightened connectors. In foreign countries, this kind of application is more common. However, for large cross-section (eg 450mm) or large diameter cables, the design of insulated wire pre-twisted fittings is difficult and there are certain limitations in use.
