The spark bursts back to life!

Electrical discharge machining (EDM) had its heyday towards the end of the previous century. At that time, 300 – 400 new die-sinking and wire EDM machines were being sold every year in France alone. Now, the technique is far less common in day-to-day operations. It has become a niche with a number of specialists carrying out machining that is almost impossible using other technologies. Machining that is necessary for producing innovative, complex components such as connectors that enable offshore oil drilling.

With a global presence, operations stretching over several sectors, distinctive Texan logo, head office in Le Mans and its name, Deutsch is a truly international company from every aspect.

High added value
Under the financial wings of the French Wendel group, Deutsch is now a recognised champion of innovation. In 2010, having acquired the Carrier company, it moved to its entirely new, 13,000 m² factory in Le Mans. Here, with just over 200 employees, operations have become specialised in components for offshore and rail traffic use.

Manufacture covers a wide spectrum – everything from one-offs to series that run into the hundreds. The company’s castings include copper, aluminium and, occasionally, brass. Duplex steels, Inconel, titanium and PLC are amongst the difficult materials it machines. Common to all these operations is the high added value that is necessary to maintain an edge over competitors.

New technology
Two design departments develop application solutions for their respective areas (offshore and rail). The development perspective is extremely important in the oil drilling sector. “Almost 70 percent of finds still remain to be exploited,” explains Joël Poullelaounen, production manager. “However, exploitation requires new technology.”

Bore holes that are deep or horizontal, go through different strata in the Earth’s crust or involve the injection of various fluids or other materials require systems that are constantly being improved. Better control devices and couplings that are increasingly precise and high-performance are examples. “Each case is unique and we must manufacture each component so that it is right from the start.”

Old technology in new application
Investment in the latest technology for five-axis milling (DMG), vibration-damped pallet systems (System 3R) and multifunction turning have enabled manufacture of ever more complex components to ever tighter tolerances. “Nonetheless, for components in Inconel or other difficult materials, complete shape control at dimensions below 0.3 mm is as good as impossible solely with conventional cutting,” adds Joël. Furthermore, the high added value in these components means that they must be right from the start.

In 2008, the design department called on the production manager and his staff to discover a solution to the above dilemma. Working with their suppliers’ specialists, a surprising solution was found – electrical discharge machining!

Automatic production cell
After “rediscovering” this technology, the methodology and machining department had its proposals accepted by company management and a new way of producing was begun. Joël: “The technical arguments convinced us and the supplier followed up with the training and service package we needed to use the technology optimally.”

In 2009, the new EDM machine, a SodickAG55L with linear motors, was installed along with a WorkPartner 2 (with the Dynafix and Macro pallet systems) from System 3R. In other words, a fully automatic production cell for series production of fibre optical components.

Finding an employee who could rapidly master the new production cell’s possibilities was now crucial. He was already there! A qualified toolmaker with long experience. Very quickly, he became familiar with the machine and the robot. “It’s an excellent configuration and I can now carry out even the most complicated tasks that the design department sets me,” is his concise verdict.

Twenty-four hours a day
Thanks to WorkPartner 2, the cell is now running all around the clock. This includes weekends. The cell’s magazine is fully loaded with blanks before the operator goes home for the break.

For two years now, EDM has been making a substantial contribution to the work done by the design and the production departments. “Because of EDM, we have sometimes been able to considerably improve connector quality. The transitions between different diameters are softer and we thus avoid the risk of, for example, damaging the fibre optics.”

Deutsch has shown that EDM has its place in modern production – but now as a high-quality cutting-edge technology. In micromechanics, EDM maintains its prominent position where small and precise shapes are concerned. These are practically impossible to produce in any other way. Especially when it is a question of difficult materials!