Common causes of poor energy storage spot welding

What causes spot weld defects & discontinuities?

There are many possible spot weld defects and discontinuities that can occur for a wide variety of reasons, but the most common reasons are contaminated parts, improper weld-ing parameters and/ or electrode geometry, poor part fit-up, and electrode wear.

What happens when a weld spot is welded?

When a weld spot is being welded, a part of the current bypasses the welding area and forms another circuit because the workpiece and the welding arm are in contact. Shunting reduces the current flowing through the welding area, resulting in insufficient heating of the weld spot and quality issues such as poor welding.

What causes a weld to separate?

Separation along the original weld plane (rather than tearing at a weld button) occur when stampings are stronger than the weld nugget. The WeldHelp Resistance Welding Troubleshooting Guide is written for operators and engineers to help diagnose and solve common spot welding defects and issues, projection welding and seam welding applications.

Why are my welds missing?

Missing welds may be the result of operator placement mistakes, or the result of machine errors in performance or settings. Undersized welds can be the product of dirty or damaged parts and materials, or of incorrect welding setups.

Do spot welds with welding defects affect mechanical performance?

Microstructure and mechanical performance of spot welds with welding defects were investigated. Although the test results here are limited, following conclusions can still be derived: • Welding defects are easy to occur during resistance spot welding of DP600 steel sheets due to its rich chemistry.

What are the factors affecting the quality of spot welding?

The heat source of spot welding is the resistance heat generated when current passes through the metal being welded. Therefore, the resistance during spot welding and its distribution are critical factors affecting the quality of spot welding.