Page 53 - MetalForming Magazine June/July 2022 80th Anniversary Issue

FABRICATION
Resistance
Welding
“Gotchas”
and How to Avoid Them
While the resistance-welding process is robust, reliable, and generally forgiving, basic knowledge of the “gotchas” of the process leads to simple, cost-effective troubleshooting.
BY TOM SNOW
The resistance welding (RW ) process, whether the spot, pro- jection, crosswire or seam ver- sion, is a tried-and-true method of join- ing sheet metal. Often the fastest and least expensive joining option, RW finds
Tom Snow is chairman of T. J. Snow Co., Chattanooga, TN; www.tjsnow.com.
As most RW machines are water-cooled, do not overlook water flow rate and temper- ature as key process variables. RW machines are thirsty and adequate water flow typi- cally is more important than water temperature.
wide use in the automotive, appliance and aerospace industries, among others. Since the RW process is robust, reli- able and generally forgiving, metal for- mers may tend to ignore the process— until quality problems occur. Then, expensive product recalls can result in
an ill-advised, kneejerk desire to switch to assembly alternatives such as expen- sive screws, rivets, adhesives or mechanical clinching.
However, basic knowledge of the “gotchas” of the RW process leads to simple, cost-effective solutions.
50 MetalForming/June/July 2022
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