METHOD OF MANUAL ELECTRIC ARC WELDING ROOT JOINT USING CURRENT MODULATED CONSUMABLE ELECTRODE Russian patent published in 2009 - IPC B23K9/173 B23K9/09 

FIELD: electricity.

SUBSTANCE: invention relates to the method of manual electric arc welding with current modulated electrodes with root joint coating and can be used for welding thin objects in different spatial positions. Additional current pulses with frequency of not less than 50 Hz are superimposed on current pauses. Duration of the additional pulses is set in the range from 2 to 7 ms, based on the diametre of the electrode and its specific type. Main current pulses, which are burning pulses, are generated in form of series of additional pulses. Duration of additional pulses in the series is set such that it is equal to duration of additional pulses in the current pause interval. Frequency of additional pulses in the series is set in the range 200…130 Hz. The number of additional pulses in the series is limited to a value which provides for formation of a key hole. Key hole formation is controlled by varying frequency of the series of additional pulses according to a schedule or automatically, in inverse proportion to the relationship between deviation of average arc voltage from a given value, equal to the nominal value for each diametre of the electrode and its specific type. Amplitude of additional pulses in the series and in pulses superimposed on current pauses with frequency of not less than 50 Hz, is set equal to nominal welding current for each diametre of the electrode and its specific type.

EFFECT: reduced size of welding baths at constant arc force, smooth melting of electrode metal and metal of the object, high physical arc stability and stability of the welding process.

2 dwg, 2 ex