Tool selection UKB
How to choose the steel for UKB press brake tooling: 42CrMo4, C45 and 1.2312
What the three UKB press brake tool steels mean, what strength they offer, why the working radius is hardened to 52–55 HRC, and how to choose according to the application.
When you order punches or dies for a press brake, the tool material is not a data-sheet detail — it determines how long the tool lasts under load and how accurate the bend stays over time. This guide explains the three materials UKB GmbH uses and how to choose between them, based on the UKB catalog.
The three base materials
UKB manufactures press brake tooling from heat-treated steels, chosen according to the working load. The strength values below are those given in the UKB catalog:
| Material | Strength (Rm) | Positioning |
|---|---|---|
| 42CrMo4 | 1,100–1,200 N/mm² | The strongest — for heavy loads and high bending forces |
| 1.2312 | 950–1,100 N/mm² | Intermediate — a balance of strength and machinability |
| C45 | 800–850 N/mm² (or 650–800 N/mm²) | Standard — for everyday applications, more economical |
Rm (ultimate tensile strength, in N/mm²) shows the maximum stress the material withstands before fracture. The higher Rm is, the better the tool copes with repeated bending forces without degrading.
Hardening the working radius: 52–55 HRC
Whichever material is used, the part that matters most is the bending radius (intake radius) — the edge that actually comes into contact with the sheet. At UKB, these radii are hardened to 52–55 HRC.
That is a high surface hardness, protecting the edge from wear and from premature marking, and keeping the bending geometry constant across the life of the tool. The rest of the tool body stays tougher (less brittle), which reduces the risk of cracking under shock loads.
What else UKB construction guarantees
Beyond the material, UKB tools are:
- Precision ground — tight tolerances along the whole length.
- Guaranteed interchangeable — a new segment fits the existing ones without adjustment.
- Guaranteed parallel — essential for an even bend along the whole length.
How to choose according to the application
The questions that decide the right material:
- How high is the bending force? Thick sheet or high-strength materials (for example stainless steel, Rm ≈ 700 N/mm²) load the tool harder than mild sheet (Rm ≈ 510 N/mm²). At high loads, 42CrMo4 is the safe choice.
- How often do you use the tool? For intensive production, the stronger material and the hardened radius extend the interval between regrinds.
- What is the budget versus the service life? C45 covers everyday applications at a lower cost; 42CrMo4 costs more but withstands greater loads.
If you send us the thickness and type of sheet you are bending, plus the make and model of the press, we will recommend the right UKB material and system — free of charge. UKB tools are held in stock at the manufacturer within 24 hours, with delivery in 1–3 working days.
See the complete UKB press brake tooling range →
Contact us for a material recommendation →