Crimp Connection
A crimp is the terminal barrel being deformed onto the conductor with a controlled force. Done correctly, no air gap is left between the copper and the terminal and a metal-to-metal contact resembling a cold weld is formed. It is the standard connection method for vehicle and machine installations subject to vibration.
The aim in crimping is not to hold the cable but to weld two metals to each other. The tool die brings the barrel to a specific profile; the strands are pressed against each other and against the barrel so hard that the oxide layer between them breaks and clean copper surfaces join.
- Signs of a correct crimp: the barrel is symmetrically deformed, a few millimetres of insulation are visible behind the barrel, the strand ends protrude slightly at the front, and it does not come apart when pulled by hand.
- A wrong crimp: a barrel that is squashed but not compressed, a half-seated terminal, or a barrel crimped over the insulation.
- Two-zone terminals: in good terminals one zone grips the conductor and the other grips the insulation; the second carries the mechanical load.
The advantage of a crimp over solder is that it does not create a stiffness transition: the crimped zone is rigid while the area right behind it is still flexible, and the vibration load spreads over the whole cable. That is why crimping is preferred on crane, tractor and machinery harnesses.
Context in which this term is used: Installation, redundancy and field continuity