Second life for reconditioned gear motors

The interior of electric motors consists largely of sought-after metals such as copper, aluminum, and rare earths such as neodymium. These are materials whose recovery is becoming increasingly important.

In view of growing resource scarcity and rising prices, solutions are needed that reduce existing dependencies. A current example of the shortage of components and raw materials is the increasing chip shortage, which is leading to production losses and delays. Standard components used in the manufacture of solar panels and many other electronic products are now also affected. According to the ifo Institute, the shortage of materials among manufacturers of electronic and optical products increased in October. In a recent survey by the institute, 10.4 percent of the companies surveyed reported bottlenecks – up from only 7.0 percent in July and 3.8 percent in April. Control mechanisms and trade restrictions, e.g., for rare earths, are leading to further shortages and higher costs. The Chinese government has imposed export restrictions that now affect twelve of seventeen different strategically important elements and are having a global impact. In the third quarter, dollar prices for these chemical elements jumped by an average of 8.2 percent compared to the previous quarter (source: Bavarian Industry Association (vbw), current monthly raw material price index). Uncertain supply chains due to fragile geopolitical developments are further exacerbating the situation. So it is not just a question of sustainability and responsible use of resources to focus on the professional processing and resale of used electric motors.

Take-back program for many years

“This approach is nothing new for us,” reports Rolf Treusch, managing director at Rotek, a small motor manufacturer based in Bremerhaven. “We have been working with a major customer for a long time and successfully recondition our motors.”

It all started with a customer in the heating technology sector who purchases large quantities of Robase motors with spur gearboxes. He is one of our top customers, with peak demand of up to several thousand motors per year. The trigger was that, as part of a product improvement, the Bremerhaven-based company had reworked and optimized motors that had been replaced by customer service. “So, we took the opportunity to completely refurbish them,” Rolf Treusch continues.

The customer then got them back. Originally offered as a service, reconditioning is now charged as a service. The customer then pays a significantly lower price for these motors. They sell them as reconditioned motors, i.e., not as new, but as refurbished. Together with this main customer, the Bremerhaven-based company therefore started a take-back program many years ago. Since then, customer service has been collecting the motors and sending them back to Rotek once a year. The delivery is then collectively overhauled.

How does the remanufacturing process work?

During production, the motors are thoroughly tested upon arrival and then mechanically dismantled. Wear parts, primarily ball bearings and capacitors, are replaced. Any visible damage is repaired. All components are then checked, for example to ensure that the gear teeth are still in good condition. The reassembled drive unit undergoes a thorough final inspection to ensure that it is in mint condition and fully functional. The motors are technically flawless, but show signs of wear. This process has proven itself.

Almost all motor components, such as copper windings and magnets, can be reused. Only the few replaced wear parts are disposed of as metal waste. No chemical or physical processing takes place. Both the copper, the copper winding, and the magnets are usually in good condition.

Engine recycling pays off in many ways

Engine recycling at Rotek arose purely from technical considerations. Originally launched as a customer service at cost price, refurbishment has now become a profitable business area for all involved. It is particularly worthwhile for larger customers, who have the opportunity to collect engines from their customers at the end of their service life and pass them on for reconditioning.

For customers, the advantage is that they can purchase technically new engines, which do show signs of wear, at a comparatively low price. And then resell them. A drive does not always have to be brand new to fulfill its tasks.

For Rotek, recycling is worthwhile for two reasons: The company significantly reduces its consumption of raw materials and energy, as key components such as the stator, rotor, and housing can be reused. Every motor that does not have to be manufactured is a relief for the environment. For Rotek, one aspect of sustainability is a durable, high-quality product: At the same time, the returned motors provide valuable insights. “Many have been in use for over ten years, and analyzing them helps us to build our products to be even more durable. This not only has ecological benefits, but also direct benefits for our customers,” explains Rolf Treusch.

The return program currently only exists for one customer and only for motors with self-built spur gears. However, there are also occasional motors that are sent in for repair. In Bremerhaven, they are repaired after a cost estimate has been provided. Rotek would like to expand the option of motor return and reconditioning in the future. It is currently considered a pilot project that will later be offered to other customers.

Engine recycling as a step toward independence

Recycling and reusing raw materials and components is particularly useful for the Rosync and Romotion series motors, which use neodymium magnets. The trade situation on the global market is also leading to a difficult procurement situation at Rotek. Rolf Treusch: “We have two suppliers for neodymium magnets, and one of them has already stopped deliveries due to trade restrictions.” This shows that it is strategically important to reuse the valuable magnetic material from old motors. At the same time, Rotek has also taken precautions in this area and built up stock for several years. In addition, Romotion in particular is currently working on a solution using other magnetic materials in order to be independent of China and its monopoly on certain raw materials.

First step toward a circular economy

Over the next one to two years, Rotek intends to significantly expand this area and offer it to its major customers as a general business model. At the same time, the Bremerhaven-based manufacturer is working on a collaboration with its partner IMS Gear. IMS Gear supplies Rotek with planetary gearboxes, which are used in large quantities. This program is not yet available for all series. The refurbishment program for gearboxes currently only covers the slightly larger series and is in the pilot phase. As soon as it is extended to small gearboxes, the company intends to offer a completely overhauled motor-gearbox unit as a sustainable, joint solution in collaboration with IMS Gear. This is also in line with Rotek's values. One of the company's core values is responsibility, also with regard to future generations: recycling and reusing raw materials and components promotes resource-efficient practices and minimizes the ecological footprint. At the same time, this second life extends the product life cycle and is a first step toward a circular economy.