Why is proper electrode pressure important in STRSW?

Why is proper electrode pressure important in STRSW?

• A. To ensure proper fusion of the metal panels
• B. To reduce noise
• C. To accelerate cooling
• D. To prevent oxidation

Answer: (A)

Proper electrode pressure controls the contact quality where the sheets meet, which is what drives fusion in resistance spot welding. When the pressure is right, the sheets are pressed firmly and evenly, allowing current to flow efficiently across the interface and heat to concentrate where the metal should melt and fuse. That creates a solid weld nugget and a strong joint between the panels. If the pressure is too low, contact is not intimate enough, causing irregular resistance and insufficient heat at the interface, which leads to weak fusion, voids, or incomplete welding. If the pressure is too high, the larger contact area can spread the current too much and reduce heat density, producing a small or weak nugget or causing expulsion. So the primary reason for proper electrode pressure is to achieve proper fusion of the metal panels.

Proper electrode pressure controls the contact quality where the sheets meet, which is what drives fusion in resistance spot welding. When the pressure is right, the sheets are pressed firmly and evenly, allowing current to flow efficiently across the interface and heat to concentrate where the metal should melt and fuse. That creates a solid weld nugget and a strong joint between the panels.

If the pressure is too low, contact is not intimate enough, causing irregular resistance and insufficient heat at the interface, which leads to weak fusion, voids, or incomplete welding. If the pressure is too high, the larger contact area can spread the current too much and reduce heat density, producing a small or weak nugget or causing expulsion. So the primary reason for proper electrode pressure is to achieve proper fusion of the metal panels.