Internal Corrosion Damage Mechanism And Residual Life Prediction Of Strain Clamp Of Overhead Line

In the process of transmission,strain clamp is bound to rely on a large number of transmission wire and hardware as wires are key hardware during the period of service,and is exposed outside,transmission when the temperature is high,and prone to corrosion,clamp process in damage,because of poor construction defects,design problems and operation environment caused by the failure phenomenon also happen from time to tome,affected the normal operation of the transmission line,research on clamp failure has become a important direction and hotspot in the research of the power transmission system.So the service line strain clamp of long-term corrosion damage mechanism and damage evolution,developed a set of indicators for temperature strain clamp of the residual life model for evaluation and guidance of transmission line operation condition,etc.It is of great significance.This paper had analyzed the failure mode of strain clamp,and studied the failure mechanism.The dry and wet alternation corrosion test was designed.The relationship between corrosion rate and environmental factors was studied.The relationship between the temperature and the surface corrosion rate was studied according to the temperature rise experiment.According to the corrosion data,the function model between the corrosion degree and the corrosion time was studied.Through the noise vibration experiment,the fault signal of the aluminum wire in the compression area was studied.Based on the above results,a method to establish the prediction model for the residual life of the strain clamp with temperature was studied.The results are as follows:(1)The reason for the failure of the strain clamp is that clamp failure mode for electric breakdown caused by arc burning,its pressure outlet has obvious arc burn marks.Strain clamp corrosion due to the early broken stocks fluid enter the accelerated corrosion process within clamp.(2)Because of the corrosion liquid in the inner surface of the strain clamp,the resulting corrosion products accumulate in the defect part and then spread gradually.And after clamp the internal corrosion liquid drying,corrosion layer micro cracks resulting from dehydration,these cracks gradually accumulate,when reaches a certain thickness,the surface layer of loose parts peeling off,after corrosion liquid will be attached to the surface again,cycle of the above process,the final form stacked corrosion layer.Clamp of the corrosion rate is closely related to the natural environment,this paper also explores the three kinds of factors affecting corrosion clamp: pH,corrosive liquid concentration,temperature,found that when the concentration increased,the temperature increasing,acid,strain clamp with aluminum corrosion rate increased.(3)The temperature rise of the temperature with the surface corrosion rate increases with the increase of the surface corrosion rate,and the temperature change rate increases successively.(4)By a laser vibration experiments verify the clamp are aluminium wire broken stocks signal found that pressure parts aluminum wire broken stocks defects in laser vibration spectrum figure high frequency phase(2000-5000 hz)appear obvious peaks,the basis of a signal can be used as clamp broken stocks.According to the corrosion data line between degree of corrosion and the corrosion time of function model,combined with the strain clamp temperature rise experiment surface corrosion rate and temperature function relation,clamp the critical parameters with temperature as the failure criterion of strain clamp residual life prediction model.