An average weld takes from three to fifteen cycles. There are three groups of time in resistance welding and they are all important. The time from the application of the electrode until the application of the welding current. The time that pressure remains on the electrodes after the end of the flow of welding current. Pressure Pressure plays a key part in welds.
Pressure assures good electrical contact of the welded part of the sheet.
In projection welding, pressure also forces the projection into the sheet after the metal reaches fusion temperature. Extreme pressure will cause projections to flatten out before reaching weld heat. Not enough pressure causes flashing, spitting, burning and discoloration. All standard OHIO Weld Products, except those with ring projections, require from 300 to 1,200 pounds pressure at the electrodes. A force gauge checks the pressure at the electrodes.