Submerged arc welding using very high current - obtd. from several power supplies with automatic control of welding voltage

摘要

Plant for arc- or plasma-welding and/or cutting, esp. for submerged arc welding, uses several individual current sources connected in parallel and with outlets joined to a burner and a workpiece. Each current source is fitted with an adjuster for voltage or current; and each adjuster is connected to the output of a controller fed with a reference value (Vr) and an actual value (Va); and the value (Vr) fed to the first controller can be supplied to the other controllers. Sources supplying a constant voltage are pref. employed, and the actual voltage (Va) is fed to the first controller together with a reference voltage (Vr) supplied by a potentiometer. Alternatively, each controller may have a potentiometer providing (Vr). The controllers are pref. differential amplifiers operating servomotors to adjust. Used to obtain very high currents, e.g. several thousand amps. for submerged arc welding.