Spot Welding
Questions and Answers
SINGLE AND DOUBLE BENDS CAN REACH THAT EXTRA DISTANCE IN RESTRICTED AREAS
Sometimes we have to reach inside a box or over a feature in a part that stretches our imagination. A double bend electrode might be the answer but a single bend electrode might also get us that extra distance. Both can be water cooled and deliver good force into restricted areas.
Reference: RWMA - Resistance Welding Manual 4th Edition
Electrodes are available in many sizes and shapes to fit most needs in industry. To choose many considerations come to mind. The first decision would be full size vs cap electrode. Are you a job shop or highly automated usually decides this.
Force is the "P" in PCT - Pressure Current and Time.The Force component of a weld schedule is required to hold the two work pieces being welded together during the welding operation. This prevents any arcing due to the parts being loose. If not held tightly molten material would be expelled during the weld operation. It also provides a forging action as the weld solidifies and cools. This forging action greatly improves the final weld strength.
AIR CYLINDER
When welding galvanized and other coated materials a layer of oxides and brass builds up on the face of the electrode. During the first twenty five to fifty welds while this layer builds up and develops equilibrium, the welding results can be inconsistent. This period is called conditioning.
EXTREME MUSHROOMING
All spot welding electrodes mushroom during use and when this happens the resultant weld eventually is unacceptable. Before this happens most operations either dress or change the electrode to get the face back to original operating conditions.
EXTREME MUSHROOMING
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