EN
In the core field of ultra-high voltage (UHV) power transmission, the performance of porcelain insulators directly determines the safe and stable operation of the power grid, and alumina powder is the key raw material supporting such insulators’ high strength, high insulating property and long service life. Greatsun Aopeng has deep expertise in alumina materials for porcelain insulators. We supply high-performance raw materials for high-voltage and UHV porcelain insulators by virtue of strict internal control standards and precise process control. Every set of test data demonstrates our commitment to quality.
I. Extreme Purity Control: Building a Solid Foundation for Performance from the Source
Our alumina powder specifically for electrical porcelain boasts an ultra-high purity of 99.736% Al₂O₃, far exceeding industry standards. This purity constructs a dense and stable α-Al₂O₃ crystalline framework for electrical porcelain insulators. High purity not only significantly enhances the mechanical strength of the porcelain body but also fundamentally reduces the interference of impurities on insulation performance, providing a solid guarantee for the stable operation of insulators under extreme high voltage and complex environments.
In terms of key impurity control, we have achieved industry-leading levels:
SiO₂ content is only 0.0194%: Lower than the industry threshold of 0.2%. This prevents softening and decreased mechanical strength triggered by excess silicon. The insulators resist cracking under thermal shock, with greatly upgraded thermal stability.
Fe₂O₃ content is as low as 0.005%: We adopt a nearly iron-free control standard. It rules out localized dielectric breakdown stemming from metallic impurities. Meanwhile, it guarantees a pure, even white porcelain body, complying with strict appearance specifications for UHV electrical porcelain set by State Grid.
Na₂O content is 0.15%: Rigorously controlled below 0.2%. It effectively restrains leakage current under high-temperature electric fields, prevents accelerated aging of porcelain parts induced by sodium impurities, and greatly prolongs the outdoor service life of insulators.
II. Precise Particle Size Control for the Full Electrical Porcelain Firing Process Particle size distribution directly affects the shaping, sintering and final performance of electrical porcelain. Greatsun Aopeng realizes precise particle size matching of alumina powder via refined process control: Median Particle Size D50 = 4.82 μm: The value falls exactly within the optimal particle size range of alumina for electrical porcelain. It guarantees favorable sintering activity of powder and avoids agglomeration triggered by overly fine particles, promoting densification of porcelain bodies at firing temperatures ranging from 1280℃ to 1320℃. Uniform and Controllable Particle Size Distribution: With narrow particle size distribution (D10 = 1.82 μm, D90 = 11.05 μm), the product lessens uneven sintering shrinkage stemming from particle size discrepancies. It effectively lowers the risk of deformation and cracking in porcelain components and raises the product yield rate. 325-mesh sieve residue stands at only 0.03%: This near-zero coarse particle control standard thoroughly eliminates latent cracks resulting from coarse impurities inside porcelain bodies, fundamentally removing hidden hazards including insulator fracture under stress and high-voltage breakdown. Raw grain size reaches 3.03 μm: This parameter balances the sintering activity and structural stability of raw materials. It guarantees adequate crystal phase growth while preventing declines in porcelain body strength induced by oversized grains, laying a stable foundation for subsequent ball milling and firing procedures.
III. Stable Physical Properties to Guarantee Batch Consistency
True Specific Gravity: 3.95 g/cm³. High true density correlates with high α-Al₂O₃ crystalline phase content, signifying a stable crystal structure and compact composition of the powder. Fired ceramic components thus boast excellent mechanical strength and weather resistance, readily satisfying the load requirements of 210 kN and 300 kN high-voltage insulators.
Whole-process quality traceability: Every batch of products passes strict tests with professional instruments including X-ray fluorescence spectrometers and laser particle size analyzers. All tests comply with GB/T6609.5-2004 standards. All indicators maintain stable compliance, delivering reliable quality assurance for downstream clients.
