Abstract: A work tank for machine tools for receiving the machining fluid comprising a fixed part and a movable part which retracts to move the tank away from the work area when it is necessary to remove a workpiece.

Abstract: A process and apparatus for accurately controlling the dimensions of a workpiece machined by EDM, by developing a linear function of the average value of the delay between the application of voltage pulses and the flow of electrical discharges through the gap between an electrode tool and an electrode workpiece. The function is linear and is an inverse function of the machining gap width to the logarithm of the average delay time. Two measures effected under well-determined machining conditions permit to develop the function with precision under such conditions, and it is thus possible to instantaneously know the real machining gap width by determining only the average value of the triggering delay.

Abstract: A metallic wire, for cutting a workpiece by electrical discharge machining, coated with at least one layer of a metal having a low temperature of vaporization and a film of a metal oxide on the metal layer. The metallic coating is preferably made of zinc and is subjected to an oxidizing thermal or electrolytic treatment such as to form on the surface of the metallic layer a thin film of zinc oxide.