In recycling yards, scrap aluminum can bales are dense and irregularly shaped, making them difficult to process with ordinary crushers. Choosing the right shredder affects not only throughput but also the purity of the final aluminum chips. Based on real cases, Haoxing Machinery Factory has summarized three points worth paying attention to.
1. Matching bale size with feed opening
Aluminum can bales are typically 300–500 mm square, with a density of about 0.3–0.5 t/m³. If the shredder’s feed opening is smaller than the bale’s diagonal length, pre‑cutting is required, increasing labor costs. It is recommended that the feed opening width be no less than 600 mm, and a hydraulic pusher be installed to reduce jamming stops. In actual feedback, lines with smooth feeding can produce 1.5–2 tons more per day than ordinary models.
2. Rotor structure and tearing ability
The aluminum layers inside the bale are tightly compressed, requiring strong tearing force to open. A single‑shaft shredder with a V‑shaped rotor is a common choice. The blade material should be high‑toughness alloy steel (e.g., Cr12MoV) with a hardness not lower than HRC55. If the bale contains small amounts of iron nails or plastic, a wear plate can be installed under the rotor to reduce damage from hard objects. When the blades wear down to about two‑thirds of their original height, they should be replaced; otherwise, output fineness will noticeably deteriorate.
3. Screen mesh size and output control
The shredded aluminum chips typically need to be controlled at 20–40 mm for subsequent magnetic separation or grinding. The screen mesh size should be selected at 1.2–1.5 times the target output size. For example, if the required aluminum chip size is ≤30 mm, a round hole screen of φ36–40 mm can be used. When processing oily or wet bales, the screen tends to clog. Adding a heating or knocking device can be considered. Some small retrofits can extend the screen cleaning interval from half a day to more than three days.
Overall, choosing the right feed opening, rotor, and screen configuration can significantly improve the shredding efficiency of scrap aluminum can bales. Haoxing Machinery Factory provides customized solutions based on different bale densities and output requirements. Feel free to bring a bale sample for a test run.
