Stranding Process Optimization for Large-Cross-Section 8030 Aluminum Alloy Conductors

To overcome the issues of high susceptibility to wire breakage during drawing, significant fluctuations in electrical resistance, and non-uniform post-annealing properties in the production of large-cross-section 8030 aluminum alloy conductors for medium-voltage cross-linked cables, and to achieve stable and efficient industrial manufacturing, optimization experiments covering the entire process chain of drawing, stranding, and annealing were conducted. A die matching formula incorporating slip and thermal expansion corrections, a quantitative model correlating stranding parameters with electrical resistance, and an annealing temperature model adapted to the conductor cross-section size were established. The experimental results indicate that the monofilament breakage rate is reduced to below 0.15 times per ton, the minimum DC resistance at 20 °C reaches 0.0456 Ω/km, the conductor tensile strength ranges from 113 to 121 MPa, and the elongation at break ranges from 15% to 16%. The manufactured 35 kV, 630 mm² medium-voltage cross-linked cable exhibits a partial discharge level of only 1.4 pC, with all performance indicators surpassing the requirements of national standards. The proposed process optimization methods effectively resolve the production challenges associated with large-cross-section aluminum alloy conductors and provide a reliable technical solution for the large-scale application of aluminum alloy cables in medium-voltage power transmission.