Crimping a wire to a terminal sounds simple, take a wire and terminal and press them together using hand or machine activated tooling. Crimping is much more than that. There is a significant amount of engineering that goes into a terminal and the termination process. The attributes that make up a terminal crimp are well established and contribute to the long term reliability of an device that uses a wire assembly.
Of course there are implications to not applying critical attributes. Implications can be minor or severe but usually mean the premature failure of the electrical device. This article focuses on one attribute that is part of the majority of terminals produced today: the serration.
What is a Serration?
Serrations are precision impressions stamped into the conductor crimp of a terminal. Although different serration designs have been used over time, typically serrations are “lines” perpendicular to the direction of the crimp. Serrations have micro-cut edges which serve a distinct purpose and function.
What is the Function of a Serration?
During the crimp process, wire is compressed into the terminal. Individual strands are compressed into the serrations. The process of compressing the strands into a serration provides a number of benefits:
- Edges of the Serration break through the oxides in a strand, decreasing electrical resistance.
- Wire embedded in a serration improves tensile forces.
- Compressive forces are spread across multiple contact forces. As stress concentration is prevented, reducing the risk of strand damage or cracking of the crimp barrel under load occurs.
Did you know?
- When comparing non-serrated crimps with serrated crimps:
- Pull Out Force (tensile) in the serrated crimp is higher.
- Electrical Resistance is generally reduced.
A Potential Cause of Crimp failure.
Wire Strands that are not embedded in the serration are a potential cause of terminal crimp failure. Failures can include low tensile testing and high electrical resistance.
Without the necessary tools, the source of the failure can be hard to determine. WireProcess Specialties has the resources and knowledge to support your crimping process, including longitudinal cross sections as illustrated above. We partner with you to Achieve More in your business by improving your crimp process.
