Terminal crimping is a critical process in creating secure, long-lasting electrical connections. Understanding its theory and performance helps ensure safety, conductivity, and reliability in electrical systems.
What Is Terminal Crimping?
Terminal crimping refers to the process of mechanically compressing a terminal onto a wire to create a strong electrical and mechanical bond. It is widely used in automotive, industrial, and electronic applications.
Wire Construction and AWG Standards
Wires consist of a conductive core (solid or stranded) and insulation. Wire sizes follow the American Wire Gauge (AWG) system. Common sizes include:
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24AWG (small)
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18AWG (medium)
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12AWG (large)
A key concept is CMA (Circular Mil Area), used to calculate the cross-sectional area of conductors:
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Single-core wire: CMA = D²
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Stranded wire: CMA = D² × N
(D = wire diameter, N = number of strands)
Example:
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D = 0.162 → CMA = 26,244 → equivalent to 6AWG
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D = 0.0152, N = 7 → CMA = 1,575 → equivalent to 18AWG
Types of Crimp Terminals
Terminal design varies based on application and wire type. Common terminal types include:
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Open-barrel terminals
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Closed-barrel terminals, such as:
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PIDG terminals (triangular insulation crimp, square/crescent conductor crimp)
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FASTON terminals (D-shaped crimp)
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Terminal Materials
High-performance terminals are often made of:
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Nickel
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Bronze
These metals provide low resistance, high hardness, и temperature resistance, making them ideal for harsh environments.
Crimping Performance and Electrical Integrity
Crimp quality is influenced by pressure, crimp height, и wire contact:
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Increased pressure → lower crimp height
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Lower crimp height → stronger mechanical bond и better electrical conductivity
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Proper crimping reduces resistance и voltage drop
Key takeaway: Correct crimping ensures long-term reliability and minimizes risk of failure in electrical systems.