Abstract
Composite insulators provide highly effective insulation support, and their application in power transmission lines has seen rapid growth in recent years. However, every year, a large quantity of composite insulators are scrapped on reaching the end of their service life. Due to the exceptional chemical inertness of the silicone rubber in the insulators, they have poor self-degradation characteristics, and end up filling landfills and occupying a lot of space, which inadvertently endangers the ecological environment. So far, there has not been any effective means to recycle composite insulators. This paper analyzes the material composition and characteristics of the silicone rubber in the core and housing of composite insulators, and proposes a resource utilization approach for the application of the pulverized silicone rubber powder from the insulators in the following three applications: use in producing silicone rubber asphalt at a blending ratio of 15%–18%—the corresponding market demand is large enough to meet the disposal needs of scrapped composite insulators; use in modification of waste rubber powder and blending with ethylene propylene diene monomer rubber (EPDM) at a blending ratio of 10%—as the annual production capacity of EPDM is more than 850,000 tons in China, thousands of tons of waste insulators can be thus disposed; and use as an aggregate for non-slip coatings, which accounts for more than 40% of the coatings material. Thus, there is tremendous scope for recycling waste insulator.
Highlights
Composite insulators have various advantages, such as simple molding and other production processes, low cost, light weight, etc., and when compared with ceramic and glass insulators, they have various advantages that solve the pollution flashover problem of the external insulation for transmission lines in polluted areas, and reduce the workload of transportation and maintenance for pollution cleaning and zero value detection
According to statistics given in Chao et al (2015), the number of composite insulators in operation has exceeded 45% of the total number of insulators on the transmission lines of the State Grid and the Southern Power Grid; in some provinces, the number is more than 70%[1]
The silicone rubber material used in composite insulator is high temperature vulcanized (HTV) silicone rubber, the raw materials of which mainly include polymethyl vinyl siloxane, reinforcing filler, constitution controller, colorant, crosslinking agent, vulcanizing agent, modified additive, etc
Summary
Composite insulators have various advantages, such as simple molding and other production processes, low cost, light weight, etc., and when compared with ceramic and glass insulators, they have various advantages (high mechanical strength, strong hydrophobicity, good pollution flashover resistance and good self-cleaning properties) that solve the pollution flashover problem of the external insulation for transmission lines in polluted areas, and reduce the workload of transportation and maintenance for pollution cleaning and zero value detection. Under the combined effects of temperature, pollution, humidity, partial discharge, or high field strength, aging of rubber occurs, manifesting in the form of fracturing, pulverization, reduced hydrophobicity, cracking, etc., during its operation. This is a serious threat to the insulation performance of power transmission and transformation equipment. Experimental studies and operational experience show that the service life of composite insulator silicone rubber materials is generally 15-20 years under normal design, manufacturing, use, and maintenance conditions[1][9,10]. The comprehensive utilization of scrapped composite insulators has just started and being in the exploratory stage, no clear-cut practical method of treatment has found acceptance as yet
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
