How to choose the right crimping tool?
A crimping tool joins conductor and contact by controlled cold forming into a gas-tight connection. This guide explains the ratchet action, interchangeable dies, the gas-tight joint per DIN EN 60352-2 and how to select by contact type and cross-section.
View crimping toolsHow does a crimping tool work?
When you crimp, the tool cold-forms the contact around the bare conductor until strands and barrel become one solid, permanent unit. No solder and no heat are involved - the mechanical pressure creates both the mechanical hold and the electrical contact at once.
A ratchet mechanism ensures the tool only releases after the full press stroke is completed. Every connection is therefore made with the same force and deformation, regardless of how hard the operator squeezes. This is the basis of repeatable, reliable quality.
What is a gas-tight connection?
A correctly executed crimp is gas-tight: the pressure cold-welds the metal surfaces of conductor and contact so tightly that no air or moisture reaches the contact zone. As a result no oxide can form there, which would otherwise raise the contact resistance over the years.
The requirements for such joints are defined in DIN EN 60352‑2 (solderless crimped connections). What matters is the correct combination of contact, cross-section and crimp profile, plus a tool that reliably reaches the specified crimp height.
Which tool suits which contact?
Selection depends on the contact type and the conductor cross-section. Wire-end ferrules, insulated cable lugs, uninsulated tab contacts and machined round contacts each call for a different crimp profile - trapezoidal, four-indent (square), hexagonal or roll crimp.
- Wire-end ferrules: square or hexagonal profile, typically 0.08 to 16 mm² for fine-stranded wires.
- Insulated cable lugs: colour-coded (red 0.5‑1.5 mm², blue 1.5‑2.5 mm², yellow 4‑6 mm²) with insulation crimp.
- Uninsulated contacts and round pins: trapezoidal or four-indent profile, often with a positioning locator.
- Coaxial and modular connectors: dedicated tools with a matching hexagonal nest.
- Always match contact manufacturer and tool profile to each other.
Interchangeable dies make one tool versatile: the ratchet frame stays, and only the crimp nest is swapped for the task at hand. This pays off when several contact types occur. For a single ferrule size, a fixed tool is often faster and cheaper.
Frequently asked questions
What is the point of the ratchet action?
The ratchet locks the tool until the full press stroke is reached and only then releases it. Every crimp is made with the same force, so the connection is repeatable regardless of the operator's hand strength.
When do interchangeable dies make sense?
Whenever you process different contact types or cross-sections. The ratchet frame stays and only the crimp nest is swapped. For a single ferrule size a fixed tool is usually enough.
How do I recognise a gas-tight crimp?
By even deformation without cut individual strands and by a pull-out force that meets the values of DIN EN 60352‑2. The cold weld prevents oxide formation and keeps the contact resistance low long term.
Can one tool crimp all cross-sections?
No. Each crimp nest covers a limited cross-section range. Conductors that are too large are not pressed enough, those too small are over-pressed. Always match nest and cross-section.
Looking for the right crimping tool?
We supply ratchet crimping tools with interchangeable dies for ferrules, cable lugs and tab contacts - for gas-tight connections to DIN EN 60352-2.
Standard-compliant
Tools for gas-tight crimps to DIN EN 60352-2.
Repeatable
Ratchet lock for consistent crimp height.
Versatile
Interchangeable dies for many contact types and sizes.
Expert advice
Our specialists help you choose the right tool.