Silicone rubber aging performance evaluation method

Silicone rubber aging performance evaluation method

Silicone rubber can be long-term reliable operation in power system, the aging resistant performance is critical. As a result, improve the aging resistance performance of the silicone material is very important. And correct evaluation of silicone rubber material in the harsh environment under the condition of aging is one of the important indicators of performance tracking and electric erosion performance, it is closely related to the service life of the insulator. Natural aging evaluation index of the cycle is long, the artificial accelerated aging experiment correct simulation in the operation of the actual tracking and electric erosion aging phenomenon, in a short period of time to evaluate the long-term performance of silicone rubber material is the problem of people remain to be researched. At present, the world widely used methods of artificial accelerated aging test method, 1 000 h salt spray method and 5 000 h aging test, the test conditions between them, test procedure, test, test results and the test evaluation are not the same.

Experiment judge evaluation: method classification ways to evaluate the aging properties and related standards should reach at least level TMA4.5, experimental conditions are easy, the experimental data in different laboratories comparable. Current standard DL/T864-2004 for insulator tracking and electrical erosion resistance of the judgment is each product flow interruption times no more than three tries, no marks, no corrosion damage to the mandrel, the umbrella skirt not breakdown.

Salt spray method is actually a longer defile the withstand voltage test, because of the corrupt liquid salt mass concentration for 10 kg/m after arc discharge dispersivity is bigger, is not easy to form a centralized ablation hot; So the assessment of tracking and electric erosion aging performance test of the quality of the liquid salt concentration or flow rate should be adjusted to a reasonable value, in order to achieve in a short time, the aging of the insulator long running performance for the purpose of a correct evaluation. Sample (s) in our hospital for large conducted the test, the results are to achieve the requirement of the trial judge, only a certain number of pitting and cracking. Not yet quantified proposed allowing erosion crack number, should further accumulation of test data, related to the operation experience of judgment is put forward.

5000 h aging experiment method of judgement and salt spray method is the same, there is also the question of arc discharging dispersion large. In addition, according to the requirements of IEC publication cycle artificial rain, rain resistance string for range is up to 15%, in the rain of the horizontal and vertical component differs also can amount to 50%, there is no doubt that cause of insulator aging performance of each laboratory evaluation of discrepancy is bigger.

Three test methods have their own characteristics, can correctly represent the natural aging process of silicone rubber, in a short period of time to evaluate the long-term performance, should further accumulation of laboratory data, and combining with the operating experience 1 000 h salt spray method and 5 000 h aging test method slops salt mass concentration and velocity of reasonable test conditions and is not stated in the current standard allows the number of pitting cracking test, so as to achieve by artificial accelerated aging to assess insulator long-term operating performance.