Analysis of Strain Clamp Failure on 500 kV Transmission Line
- 1 State Grid Liaoning Electric Power Research Institute, Shenyang, China
- 2 State Grid Shenyang Electric Power Supply Company, Shenyang, China
- 3 State Grid Liaoning Electric Power Research Institute, Shenyang, China
- 4 State Grid Liaoning Electric Power Research Institute, Shenyang, China
- 5 State Grid Liaoning Electric Power Research Institute, Shenyang, China
Abstract
In this work, the main reasons for the breakage of 500 kV transmission line are studied. Under low temperature condition, the coverage of the ice results in the disconnection between the aluminum tube and the steel anchor of strain clamp. Using macroscopic analysis, structure stress analysis, force analysis and mechanical property test, the fractured strain clamps are investigated. The crimping of the aluminum tube on the polished rod not on the grooves of the steel anchor leads to the damage of the strain clamps, which is defined as improper crimping. When improper crimping emerges, there will be only friction force between the aluminum tube and the steel anchor without shear force, and the tension of the conductor will be mainly supported by the steel strands which should be supported by both the aluminum tube and steel stands. Therefore, the breaking force of the strain clamp will greatly decrease. The failure analysis helps to promote the proper hydraulic crimping process and the safe operation of the transmission line.
- Ma, X.Ch., Gao, L., Zhang, J.X. and Zhang, L.Ch. (2017) Fretting Wear Behaviors of Aluminum Cable Steel Reinforced (ACSR) Conductors in High-Voltage Transmission Line. Metals, 7, 373. https://doi.org/10.3390/met7090373
- Aggarwal, R.K., Johns, A.T., Jayasinghe, J.A.S.B. and Su, W. (2000) An Overview of the Condition Monitoring of Overhead Lines. Electric Power Systems Research, 53, 15-22. https://doi.org/10.1016/S0378-7796(99)00037-1
- Liu, C., Xiong, L., Chen, H.D. and Li, X. (2010) Fracture Analysis of Steel Anchor for Tension Line Clamp of 500kV Transmission Line. Shanghai Electric Power, 4, 264-266.
- GB/T 3428-2002. Galvanized Steel Wires for Overhead Stranded Conductors.
- GB/T 1179-2008. Round Wire Concentric Lay Overhead Stranded Conductors.
- Huang, N., Zhang, Y., Pan, L.B. and Yang, L.Z. (2012) Analysis of Strain Clamp Fracture in 500 kV Transmission Line. Guangxi Electric Power, 35, 63-65.
- Zeng, X.J., Luo, X.L., Lu, J.Z., Xiong, T.T. and Pan, H. (2012) A Novel Thickness Detection Method of Ice Covering on Overhead Transmission Line. Energy Procedia, 14, 1349-1354. https://doi.org/10.1016/j.egypro.2011.12.1100
- Wang, Z.J. (2017) Recent Progress on Ultrasonic De-Icing Technique Used for Wind Power Generation, High-Voltage Transmission Line and Aircraft. Energy and Buildings, 140, 42-49. https://doi.org/10.1016/j.enbuild.2017.01.072
- Chen, G.H., Wang, X., Wang, J.Q., Liu, J.J., Zhang, T. and Tang, W.M. (2012) Damage Investigation of the Aged Aluminum Cable Steel Reinforced (ACSR) Conductors in a High-Voltage Transmission Line. Engineering Failure Analysis, 19, 13-21. https://doi.org/10.1016/j.engfailanal.2011.09.002
- Hu, J.R., Liu, C., Ouyang, K.J., Xie, Y., Mou, S.Z. and Chen, Y. (2012) Analysis on Cracking Failure of Strain Clamp on 500 kV DC Transmission Line. Electric Power Construction, 7, 82-85.
- Li, X.H., Wu, H.L., Ding, H. and Zhu, C.L. (2014) Simulation and Failure Analysis of Strain Clamp Failed Caused by Deterioration of Contact Resistance. Recent Advances in Structural Integrity Analysis—Proceedings of the International Congress (APCF/SIF-2014), 212-217.