EDM Magnetic Chucks Enhance Productivity Through Palletization
As with most magnetic work holders, EDM chucks provide uniform, full magnetic holding coverage through the entire surface with the work piece. CNC programming is simplified since setup, changeover and destroy rates are drastically reduced.
The EDM process is popular by moldmakers, but is also used to manufacture prototypes, parts of complex shapes, difficult materials with close tolerances, or low quantity production parts within the aerospace, automobile and electronics industries. Traditionally, EDM work pieces were clamped and strapped onto plates. This caused more setup time, an inability to position multiple work pieces on a single plate, a failure to automate and caused more complex CNC programs. EDM magnetic chucks remove the unproductive unwanted effects of mechanical clamping.
Introduction to EDM Magnetic Chucks
EDM magnetic chucks are created from encapsulated ceramic or Neodymium (rare earth) permanent magnets and can be controlled mechanically or electronically depending on the application. They employ a low magnetic height to attenuate secondary erosion. A fine magnetic pole distribution offers a uniform magnetic holding force that permits for sparking parts nearer to the chuck surface to eliminate interference through the magnetic field from distorting the EDM process. Additionally, the fine pole design will not obstruct flushing. Like all magnetic work holders, EDM chucks provide uniform, full magnetic holding coverage over the entire surface area of the work piece. CNC programming is simplified since setup, changeover and destroy minute rates are drastically reduced.
EDM magnetic chucks might be controlled manually using a lever that turns the magnetic force off or on. No electrical power is needed, passing on portability and an intrinsic failsafe feature. They can also be controlled electronically, giving the chuck an adjustable holding force, in two ways: electro-permanent and electromagnetic control.
Electromagnetic chucks are constructed with electrical coils wound around a steel core embedded in the chuck. To energize the electromagnetic field, a chuck controller is utilized to develop a variable DC voltage inside the chuck's coils. The chuck's poles are magnetic provided that voltage is used. The operator can adjust the controller's DC voltage to alter the potency of the magnetic field, which, consequently, provides variable holding force.
Electro-permanent magnetic chucks (commonly called electroperms) are a hybrid from the permanent and electromagnetic chuck types. They may be made with a coil wound around magnet material embedded in the chuck plate. When a DC voltage is applied, the magnetic materials are charged, that can take about 1 second, and props up workpiece even after power is removed. They have got variable holding power capability comparable to electromagnetic chucks. Power is needed is de-energize the magnetic field. This provides both of them a failsafe advantage over electromagnetic chucks and eliminates the accidental discharge of work piece.
The benefit Automation
EDM magnetic chucks tend to be flexible and taking machining multiple parts with one setup or several parts of varying dimensions. Conventional chucking would require much more setup time and energy to get ready for the EDM process. Another advantage of magnetic workholding is palletization. In one setup, EDM pallets could be moved from a 5-axis machine, to the EDM, drilling operation, or some other machine that is build for pallets.