Lincoln Electric IM649 manual Figure A-2. Weld Droplet Transfer

Appendix A PULSE WAVE SHAPING PRINCIPLES A-3

FIGURE A-2. WELD DROPLET TRANSFER.

SPRAY TRANSITION

CURRENT

PEAK AMPS

TAILOUT

BACKGROUND AMPS

T1 T2 T3 T4 T5

WELD

DROPLET

TRANSFER

•From time T1 to T2:

•From time T2 to T3:

•From time T3 to T4:

27850028

Background current maintains an arc, and a weld bead starts to form.

Ramp-up current forms the weld droplet at the tip of the electrode.

Peak current and peak time separate the droplet and propel it toward the weld surface. The arc width and transfer force are controlled by peak current and peak time.

•	From time T4 to T5:	Tailout current controls the heat input to and agitation of the weld
		puddle. Shorter tailout contributes less heat to the weld. (The level of
		background current also affects the weld heat.)
•	After time T5:	The waveform repeats to start the weld droplet transfer process over
		again.

EACH PULSE DELIVERS ONE DROPLET OF WELD MATERIAL 27850029

WAVE DESIGNER