High-speed rail catenary is an important carrier for train power transmission. Because of its high strength and good electrical conductivity, ACSR conductors have become common conductors for catenary bearing cables and contact lines. However, in the high-speed rail operating environment, ACSR conductors are facing various challenges such as vibration fatigue, mechanical wear, electrical corrosion and severe weather erosion. At this time, preformed armour rods for ACSR conductor relies on structural advantages and performance characteristics to become an important metal tool to ensure the safe operation of the catenary.
The application of preformed armour rods for ACSR conductor in high-speed rail catenary is manifested in the protection of key connection parts. In the catenary system, the connection point between the ACSR conductor and the insulator, wrist arm, bearing cable seat and other metal fittings is the stress concentration area. The disturbance of air flow generated by the high-speed operation of the train will cause high-frequency vibration of the conductor, which can easily lead to fatigue cracks or even fractures in the connection parts under long-term action. Preformed armour rods for ACSR conductor adopts multi-strand high-strength aluminum alloy or galvanized steel wire preformed and formed. When installed, it is tightly wrapped around the connection point and the surface of the nearby conductor by spiral winding. Through the design principle of stress dispersion, the concentrated stress is evenly transmitted to a wider range of conductors, reducing the peak local stress.
Preformed armour rods for ACSR conductor also play an important role in wire damage repair and reinforcement. Long-term exposure of the high-speed rail catenary to the outdoor environment may cause local wear and tear of the ACSR conductor, broken strands, etc. due to lightning strikes, foreign body impacts, bird pecking, or accidental construction injuries. If not treated in time, the damaged area will produce electrical corrosion due to the concentration of current, accelerate the aging of the conductor, and even cause disconnection accidents. The traditional repair method requires the wire to be cut off and reconnected, which not only has a long construction cycle, but also affects the normal operation of the train. Preformed armour rods for ACSR conductor can choose the corresponding specifications according to the degree of damage, and wrap directly around the damaged area. Through the mechanical fastening force of the joint box structure and the conductor, an integrated force system is formed, and the mechanical strength and electrical conductivity of the conductor are quickly restored.
In addition, in the strengthening of protection in harsh environments, preformed armour rods for ACSR conductor also showed strong adaptability. High-speed rail lines often pass through alpine, high-humidity, coastal or sandy areas, and ACSR conductors are susceptible to low-temperature frostbite, salt spray corrosion, and sand and dust wear. For salt spray corrosion in coastal areas, armored protective lines made of galvanized steel or anticorrosive aluminum alloy are used. The dense oxide layer or galvanized layer formed on the surface of the protective line can effectively isolate the contact between seawater and the conductor and delay the corrosion rate. In windy and sandy areas, the spiral structure of the guard line can reduce the direct scouring of sand and dust particles on the surface of the conductor and reduce the degree of wear. At the same time, in the anchor joints, curve sections and other complex parts of the catenary, preformed armour rods for ACSR conductor can also be used with other metal fittings to enhance the tensile and bending resistance of the conductor, adapt to the dynamic force changes when the train passes, so that the catenary can operate stably under complex working conditions.
In short, the preformed armour rods for ACSR conductor provide safety protection for the ACSR conductors of the high-speed rail catenary by dispersing stress at important connection sites, quickly strengthening in damaged areas, and strengthening protection in harsh environments.