Avoiding Electrical Failures: Potential Risks And Alternatives Of Secondary Crimping With Cold-pressed Pins
In industrial cabling, some operators, in order to save time, often consider crimping the crimp contact male terminals again when faced with terminals that have already been crimped. While this may seem to increase stability, it is actually a typical no-no in electrical connection operations. This indiscriminate application of pressure not only fails to improve contact problems caused by an imperfect initial crimp, but also damages the original physical properties of the metal.
Metal Fatigue and Microstructural Destruction
The core of cold pressing technology lies in the cold plastic deformation of the metal, also known as cold welding. Upon initial compression, the metal wall of crimp socket contact and the conductor core have already undergone molecular-level displacement and fusion. Applying pressure again will cause severe work hardening of the already deformed metal.
This hardening makes the material brittle, making it extremely prone to cracking or even breakage under subsequent vibration or thermal expansion and contraction cycles. The originally dense connection may develop tiny gaps due to secondary deformation, allowing moisture and oxygen to enter and inducing oxide layer buildup.
The Hidden Danger of Increased Contact Resistance
Many people believe that the tighter the crimp, the better the conductivity. The opposite is true; excessive compression reduces the effective cross-sectional area of the conductor core. After being subjected to secondary damage, the stress distribution inside the female crimp contact becomes chaotic.
Uneven stress points create localized high-resistance areas. When current flows through these areas, they heat up rapidly, accelerating insulation aging. Over time, what should be a long-lasting connection becomes a potential ignition point.
The Correct Handling Logic
When encountering improper crimping or failed tensile tests, cutting it off and redoing it is the lowest-cost and lowest-risk option. The damaged section of wire was scrapped, the wire was stripped again, and a brand new male crimp contact was used for standard operation.
Selecting a die matching the wire diameter and crimping it correctly in one go avoids a series of problems such as insulation damage and insufficient insertion/extraction force. Maintaining standardized work practices is far more meaningful than trying to repair a defective product.
