The Research On Surface Contact And Wear Of Overhead Transmission Wires

Overhead transmission wires are often under high-frequency vibration state when they work in wind load. Therefore minuscule relative motion would happen between wires. That can cause wear and friction, accelerate the crack initiation and expansion, and significantly reduce the fatigue life of the wire. The main research topic is stress distribution between the contact surface of aluminum wire in different layers and the wear mechanism caused by Aeolian vibration. Theoretical and experimental basis for enhancing wire operational life and reducing the wire wear have been provided.In this paper, based on the wire wear simulation test, the wear mechanism of ACSR has been studied by finite element method and micro-wear analysis method. (1) Stress research shows that stress concentration and wear state on the wire around clip are more serious because of the effects of tension and self-weight. (2) When wire tension is 0.08 times, 0.16times and 0.25 times the calculation breaking force, the complex stress distribution, contact pressure and friction shear force in aluminum wires contact region have been calculated by Abaqus software. That provide data infrastructure for wear mechanism analysis. (3) Wire vibration under 0.08 times the calculation breaking force has been simulated. After 105,106,107 times vibration frequency test, the microstructure of wear region and wear dusts on the ACSR have been observed. Wear process and mechanism have been analyzed. Experiments show that, by the influence of wire contact stress, vibration amplitude and vibration angle etc, the superficial aluminum layer in contact region desquamates and migrates in early stage of wire fretting, then the next layer turns. Plastic flow, hardening and physical properties changes occur on that superficial layer because of higher contact stress. That layer is more easily to slip, break off and turn to wear dusts by disintegration and transportation when the vibration happens. One part of dusts moves out of contact region. Other part of dusts moves into contact region, and disintegrates into smaller dust and aggravates wear. The ware state turns to stable stage after 107 vibration frequency.The analysis results in this paper have a certain value of theoretical guidance for reducing wire wear and improving the fatigue life of wire. Those results can also provide experimental and theoretical basis for optimization of conductor design and optimization of line construction process.