The focus in hardening is on dimensional accuracy

Shorter model life-cycles and increasing demands on quality, accompanied by many technological innovations, are driving developments in high-tech industries –
such as car or aircraft manufacture – ever harder. The effect this has on the production environment is best shown by the example of hardening. Many of their key components go through this process at one stage. It is a process that has to be not only highly accurate. It also has to guarantee unvaryingly good component quality.
It is for this reason that the specialists at eldec have committed themselves wholeheartedly to the required standard of reproducibility. Their MIND modular hardening machines stand for exceptional precision and economic processes.

“Reproducibility“ is an inalienable word in car production. After all, the car as a product is reliant on the unvarying component quality of the drive shaft. In this context, the focus is on the indispensable hardening process.  It is well to remember that during this process the component‘s micro structure undergoes a change that considerable improves its stability. It is the reason why this key process has to guarantee constant reproducibility.

Where quality matters ...
The eldec experts are very well aware of the fact that the interaction between key components – such as inductors, generators and coolant systems – and a multitude of other components – such as indexing tables, spindle drive and control system – is of the utmost importance. Over the last three decades, the company – with headquarters in Dornstetten, near Freudenstadt, Germany – has further developed their hardening technology. And in February eldec became a part of the EMAG Group. Precision and the integrity of the production process are important to the eldec experts, as Dr Christian Krause, Head of Application Technology, makes plain: “We are frequently contacted by companies that require their components to be of exceptional quality. We can guaranteed that with our system technology.“ At the centre of it is the MIND (Modular Induction) hardening machine, offered in the variants MIND, MIND-M and MIND-S and their different sizes. Generally speaking, using modular technology, the machines are configured to suit individual workpiece dimensions, hardness profiles and production requirements. The modular system ensures that only well proven components are used. This increases machine stability and guarantees that the technology can be offered at an advantageous price-performance ratio. “Engineering of the machine is, of course, greatly influenced by the workpieces to be hardened“, explains Herr Krause. “Requirements are discussed in detail with the customer. This is followed by the gradual assembly of the eldec MIND-system, selecting the required key components: basic machine, energy source, inductor, coolant system and – where required – the automation components.”

High efficiency, precision dosing
For every machine component, the machine builder relies on quality details and the accumulated know-how. The result is a machine that considerably improves the economic viability of the process.

• Example: basic machine. The base is constructed of massive, high-precision welded components and includes the main column for the Z-axis. The vibration resistant construction ensures great machining accuracy. Depending on the clamping system used, eldec machines can accommodate workpieces of up to
  1,200 mm diameter.
• Example: generator. Available are micro-processor controlled single- or dual-frequency generators with a capacity of 5 to 3,000 kW. They are highly efficient and allow for the required energy to be adjusted with great precision. Their performance also adjusts itself automatically, and with equally great precision, to that of the inductor used. 
• Example: inductor / tools. These are manufactured according to customer specification, using 3D-CAD software. They are of micrometric accuracy and made with the help of state-of-the-art machinery and experienced staff.

Even the simplest performance data of the MIND-technology from eldec is bound to impress. For instance, a driving pinion is processes in as little as 14 seconds.
The component is inserted into the indexing table of the machine either automatically (for instance by robot) or manually. Depending on the workpiece, the hardening process takes between 100 milliseconds and a few complete seconds. After quenching, the hardened steel is gradually tempered. The machining cycle is completed with the subsequent cooling process. “Of decisive importance to us is not just the enormous speed of the process, but also the precision of the hardening operation”, explains
Herr Krause. “For instance, on eldec machines the variation in effective hardening depth is no more than ±0.1 mm – an extremely low value when it comes to hardening.”

Benefitting from the general trends
With this background, it is hardly surprising that eldec is benefitting from the general trends in the automotive and aviation industries. The geometries of many components are becoming more complex and, at the same time, the pieces tend to get smaller.  The hardening process has to keep pace with this development and guarantee the required quality despite more demanding basic conditions. With their MIND series of machines the experts have made a brilliant start. The eldec machine builders have even lent more flexibility to the workflow by providing a suitable degree of automation. Their machines are now available in versions ranging from manually loaded stand-alone solution to fully integrated in-line hardening cells for the soft and hard machining of components.  

It is in the emerging markets in Asia in particular, where the highly flexible use of these machines scores heavily. Here, large automobile manufacturers put their faith in
eldec machines when they are building their new production facilities. “In China, for instance, the production quality of components has to be on par, in every respect, with that in Europe or the USA. And we offer the hardening machine technology they need. It is a technology that impresses with its economic processes“, concludes Herr Krause.