In order to determine the One-Drop One-Pulse (ODOP) condition of the pulsed gas metal arc (GMA)
welding, the drop detaching phenomenon during the peak time is investigated using the force-displacement
model. The drop detaching criterion is established based on the displacement of the pendant drop, and the
forces exerted on the drop are calculated using the Modified Force Balance Model (MFBM). The effects
of wire melting on the drop size and force are included in the force-displacement model. While the peak
current has most significant effects on the drop detaching time, the initial drop mass prior to the peak
time also influences drop transfer. The calculated results show good agreements with the experimental data,
which implies that the ODOP condition can be predicted using the force-displacement method.