Aluminium casthouses are being asked to use more recycled metal without compromising melt quality, recovery rates or production efficiency, and lighter feedstock makes that harder. Post-consumer recycled aluminium, lightweight scrap and machining chips are difficult to introduce into conventional melting furnaces, making efficient scrap feeding and submergence central to recycling performance. Circulation and stirring equipment must also support heat transfer and consistent temperature and composition across the bath while limiting interruptions and metal loss.
Immersed hardware and its limits
Conventional mechanical pumps, though widely used, depend on immersed rotating components that can deteriorate through exposure to molten aluminium, dross accumulation and refractory debris. Zmag America, Ltd. works in this specialised corner of casthouse technology, developing magnetic engineering solutions for molten-metal circulation, furnace stirring and scrap recovery.
The company's roots are in industrial magnets and magnetic circuits, tracing to magnetic engineering and commercialisation of eddy-current separation, which recovers non-ferrous metals from mixed streams. It later moved into molten-metal applications, developing its patented zPMC (Zmag Permanent Magnetic Circuit) as the basis for equipment that stirs, circulates and submerges material. Unlike conventional electromagnetic stirring, the zPMC uses a permanent magnetic circuit to generate the moving field, producing what Zmag calls a virtual impeller — circulation without immersed mechanical impellers.
In an August 2025 interview with AL Circle, Zmag America president Eishin Takahashi named limited familiarity with the technology as a barrier to wider US adoption, observing that aluminium producers globally tend to be conservative and prefer equipment and processes they already know.
MagStir targets furnace homogenisation
MagStir is a non-contact stirring system for melting and holding furnaces that uses the permanent magnetic circuit to move the bath and support homogenisation of temperature and alloy composition. Zmag offers configurations for furnaces of 15 to 200 metric tons; with no immersed mechanical stirring component, the system is pitched at casthouses seeking better melt circulation without extra moving parts in the molten-metal environment. New Zealand Aluminium Smelters installed it in a casting furnace and later extended it to other furnaces, and a 2017 technical case study of those installations reported improvements in temperature control during furnace preparation. A MagStir unit was fitted to a casthouse furnace at Rio Tinto-operated Boyne Smelters in Queensland, Australia, in 2019.
MagPump as a non-impeller alternative
MagPump extends the same approach to pumping and circulation. It fits a standard pump well without furnace modification, has no physical impeller and is marketed as a nearly hands-free option with no consumable parts and minimal downtime. At the TANDEM Division of US secondary producer TST Inc. in Fontana, California, a seven-week trial replaced an existing mechanical pump in a production furnace; findings described smooth operation and reduced disturbance to the molten-metal surface, and plant management reported the system avoided the splashing seen with conventional pumping as metal level fell during draining. The technology was presented at TMS 2023, covering its use in side-well, multi-chamber furnaces and potential roles in gas injection and scrap submergence.
Typhoon for difficult scrap
Typhoon targets scrap submergence and chip melting, drawing lightweight scrap and machining chips beneath the molten-metal surface rather than letting them float; its magnetic circuit generates vortex-like movement that pulls material into the melt, supporting heat exchange and recovery. At Neuman Aluminium's Marktl facility in Austria, the system formed part of a furnace modernisation to expand processing of low-density post-consumer scrap, including fractions of about 375 kg/m³ bulk density that had challenged conventional charging and melting. Neuman had targeted one metric ton per hour while continuing to melt solid charge in the same furnace; the Typhoon system processed almost twice the planned scrap quantity within the expected time without disrupting normal operations, with low operator involvement and, according to the company, no negative effect on melt or finished-product quality. The published technical account says it operates at 5-15 kW including its air-cooling blower, can submerge up to five metric tons per hour of machining chips, and allows vortex intensity to be adjusted to keep metal moving when scrap is not being charged.
Competitive landscape
Established suppliers populate the market, though not all offer direct equivalents. ABB supplies AL-EMS electromagnetic stirring for melting, holding and alloying furnaces and reports more than 430 installations; in April 2026 it announced a further Arconic order for a fifth stirrer at a Hungarian casthouse. Presezzi Extrusion Group's Melting Technology division offers the L.E.C. (Low Energy Consumption) Stirrer. Pyrotek covers electromagnetic pump systems and its LOTUSS (Low Turbulence Scrap Submergence) technology, which uses a circulation pump and refractory well; its UK operations include EMP Technologies Ltd. Rockwell Automation works in adjacent industrial automation, including furnace and ladle-shop control systems for Mozal Aluminium's casthouse.
As producers take on harder recycled feedstock, managing molten-metal movement without conventional immersed mechanical components may become a more relevant consideration.