Sodick and JauchSchmider Lead the Way for EDM in Aerospace
The French aerospace industry is leading the way in its use of advanced EDM technology for the manufacture of highly engineered components.Â Although long established in the general manufacturing arena, EDM has only recently taken its place among the technologies used by aerospace suppliers - however, those organisations that have taken the plunge are already reaping significant benefits.
EDM technology has been developing at an astonishing pace, led in large part by the work of development engineers at the world's leading EDM supplier, Sodick. A decade ago the company introduced the world's first linear motor drive, high speed CNC EDM machine.Â Last year it celebrated manufacturing its 20,000th linear motor EDM machine and now has factories in Japan, China and Thailand, and a workforce of over 3,500 staff in countries around the globe, supporting distributorships in many countries across Europe, including France, Italy, Germany, Portugal and the UK.
The latest generation of award winning Sodick EDM machines provide, as standard, 5-axis capability, the direct import of 3D solid modelling into the numerical controller, graphite electrode wear rates of less than 0.06%, defined as “nano wear”, and are supported by a unique 10 year accuracy warranty.
However, the development which has proved of most interest to aerospace designers, and a unique feature of the Sodick solution, is the option to upgrade the controller to handle 8-axis simultaneous EDM machining operations. This capability provides the major advantages of eliminating the need for multiple set-up operations while at the same time removing the complexity of integrating additional controllers to achieve the same machining capabilities.
This means that highly complex geometries can be machined out of a single piece of material, providing added strength and integrity, dramatically increasing machining flexibility and enabling the creation of forms whose 3D shape is only limited by the technical imagination of the designing engineer.
EDM is ideally suited for working very hard or “difficult” materials such as hardened tool-steel, titanium, carbide and inconel. Small wonder then that aerospace engineers are adopting the technology which is so ideally suited to their requirements for reliability, extreme precision and fine tolerances.
Integrated Multi-Axis Machining
To create the integrated solutions for which these engineers are searching Sodick and its technical distributors have established a long-term partnership with JauchSchmider, the premier manufacturer of a wide range of high precision rotary tables, which can be supplied with or without a closed loop system fully integrated into the Sodick controller.
JauchSchmider multi-axis rotary tables, used in combination with Sodick wirecut and diesink EDM machines can produce tighter and sharper contours, micro structures, and micro holes with diameters of 80microns, approximately the thickness of a human hair. Indeed, it has been JauchSchmider's experience that the trend in many industry sectors, but particularly in medical and aerospace manufacture, is for component sizes to shrink – the shapes stay the same, but the overall sizes become smaller. The technical challenge is that when the part size is reduced, the tolerance also becomes proportionally smaller.
The complex shapes which are common in the aerospace sector have traditionally been created in several different machining operations, necessitating multiple set up operations, which has inevitably led to inaccuracy. The answer is 8-axis simultaneous EDM machining, which can produce tight tolerances and complex shapes.
Such capabilities have obvious attractions to aerospace companies and recently a team of Sodick engineers in France, together with staff from Celada, their representatives in the country, have prepared, tested and installed two multi-axis Sodick EDM solutions, one a diesink machine, the other a wire machine, complete with robot loaders, for major customers in the aerospace sector, one a key subcontractor, the other in an aircraft motor manufacturer.
Die sinker Drills Ultra-precise Engine Parts
The first machine, which has been installed in the aero engine machine shop, is a Sodick AG55L die sinker, equipped with an LP10 Controller capable of handling 8-axis simultaneous machining through the integration of a JauchSchmider A and B axis (rotary and tilt) on the machine table.
If such an complex integration task would daunt some engineers, it certainly did not overawe the Sodick/Celada team who are highly skilled at integrating components from different manufacturers to create one-off bespoke solutions for their customers.
The tasks carried out by the AG55L are, naturally, highly confidential, but include the machining of ultra-precise components in which a hundred holes of less than 0.8mm diameter are created at different angles. This type of machining is of course extremely time consuming, but one of the great strengths of the AG55L machine in this configuration, which includes a pallet-handling robot, is its ability to run unmanned, greatly boosting its productive capacity, and, with an average work time of two hours per pallet, the machine can be left unattended for a full 24 hours.
Wire Eroder Manufactures Command Components
The second machine, a Sodick AQ327L wire eroder, is providing an equally productive solution for an aerospace subcontract supplier, who is using it to manufacture command components.Â Once again a JauchSchmider horizontal rotation A axis has been integrated to provide 8-axis simultaneous machining capability using a Sodick LP34 controller, ensuring accurate positioning through continuous rotation, to enable the creation of ultra-thin slots and complex precise shapes using very small diameter wire.
This system is also provided with a robot loading system, capable of loading 24 pallets successively and again able to run unattended for 24 hours. In addition a hot air blower system has been integrated to dry components as they leave the machine to avoid the corrosive effects of the dielectric fluid.
EDM, Aerospace and Europe
Jan van Egmond, President of Sodick Europe, believes that there will be a growing demand for high-end EDM in the aerospace market; EDM is already an established technology in the manufacture of surgical and medical items, a sector which is almost as demanding as aerospace in regard to precision and accuracy, and where each component carries a high engineering value-add.
“In aerospace, up to now, engineering companies have had to put up with solutions which were less than perfect, because that was all there was. Now, with Sodick's fully integrated multi-axis machines, engineers can create the high value components on-time, every time, reliably and consistently. No wonder some of them are keeping the secret to themselves.”
“Sodick's market share in Europe has been growing rapidly, from a base of 4 % in 2000 to 20% in 2007, and with 500 machines sold this year in Europe alone. How do we explain this growth? Simple, it is the direct result of Sodick's 32 years of total dedication to creating the very best EDM machines to match its customers' real machining needs.”