Why is proper electrode pressure important in STRSW?

Why is proper electrode pressure important in STRSW?

• A. To prevent oxidation
• B. To ensure proper fusion of the metal panels
• C. To cool the weld quickly
• D. To improve mold release

Answer: (B)

In STRSW, the electrode force is what makes the weld possible. The two electrodes clamp the sheets and pass current through the joint, so the pressure they apply creates and maintains intimate contact at the interface. This contact concentrates heat where the metals meet, allowing the materials to melt and fuse together into a solid nugget that ties the panels into one piece. If the pressure is too low, there’s poor contact, gaps, and uneven heating, which leads to weak, inconsistent fusion. If the pressure is too high, you can crush the sheets or cause excessive electrode wear and burn-through, degrading the weld. So the correct reason for proper electrode pressure is to ensure proper fusion of the metal panels. Oxidation prevention, rapid cooling, or mold release aren’t the primary roles of electrode pressure in this welding process.