Flat springs

Our flat springs, stamped parts, and bent components are primarily manufactured from carbon steel spring strip. Special materials can be used upon request.

Processing is carried out using eccentric presses with a pressing force of up to 63 tons, as well as Bihler stamping and bending machines (RM30, RM50, and GRM 80E), offering a punching capacity of 30 tons and a bending capacity of 5 tons. These machines can handle material thicknesses from 0.10 mm to 1.00 mm and widths from 2.00 mm to 60.00 mm. As part of our process-controlled development, the required tools are designed and manufactured in our in-house tool shop. This ensures that planning and production are closely aligned from the outset. Modern software such as Autodesk AutoCAD, Inventor, and FEM-based simulations is used in the tool design process. Many flat springs undergo heat treatment after production. Depending on customer requirements, a wide variety of surface coatings is available.

Materials

Surface Treatment

Tools

Data Formats

Contact Person

Designation	Material Description	Load, Properties, Applications
DIN EN 10088 – 1.4301	(X5CrNi18-8)	Stainless material for use at elevated temperatures; lower cold work hardening than 1.4310; not spring-hard.
DIN EN 10151 – 1.4310	(X10CrNi18-8)	Stainless material suitable for use at elevated temperatures.
DIN EN 10151 – 1.4401	(X5CrNiMo17-12-2)	Non-magnetic, more corrosion-resistant than 1.4310.
DIN EN 1654 CuSn	Bronze	Non-magnetic, electrically conductive.
DIN EN 1654 CuZn	Brass	Non-magnetic.
DIN EN 1654 CuNiZn	Nickel Silver	Corrosion-resistant and electrically conductive.
DIN EN 10132	Carbon Steels (C-steel)	Soft or pre-hardened.

Other materials for special applications are available upon request.

The above information is for guidance only and is not intended to be exhaustive.

When using stainless spring wires and strips, additional corrosion protection is generally not required. However, if a non-corrosion-resistant material is selected for technical or economic reasons, appropriate corrosion protection should be applied afterward, if necessary.

Shot peening enhances the fatigue strength of springs but does not provide corrosion protection. Any required corrosion protection must therefore be applied separately. Below is a selection of surface treatments we offer. If the specific treatment you require is not listed, please don’t hesitate to contact us:

Surface Treatment	Note
Zinc Plating	Electrolytic zinc plating is the most commonly used and cost-effective corrosion protection method for technical springs.
Zinc Plating with Passivation	Zinc plating followed by passivation offers cost-effective corrosion protection for technical springs.
Nickel Plating	Nickel plating is a decorative surface treatment with good sliding properties and high corrosion resistance.
Chrome Plating	Chrome-plated parts are decorative and offer excellent heat and corrosion resistance.
Pickling	Pickling removes chemically bound impurities from the surface.
Copper Plating	Often used as a base layer for other coatings but also for color marking of springs.
Bluing (Black Oxide)	Forms an iron oxide layer with a deep black surface; oiling adds corrosion protection.
Phosphating	Used for corrosion protection and as a primer for paint coatings or KTL (cathodic dip coating).
Zinc Flake Coating	An environmentally friendly, chrome-free system with high corrosion resistance, temperature stability, and minimal hydrogen embrittlement.
KTL Coating (Cathodic Dip Coating)	A high-quality immersion coating that provides outstanding protection against corrosion and underfilm rusting.
Powder Coating	Offers scratch- and impact-resistant surfaces with excellent corrosion protection.
Gleitmo	Air-drying lubricant coating based on PTFE, resistant from -180°C to +250°C, provides low friction, is non-greasy, clean, and food-safe.
Tin Plating	The primary advantage of tin plating is good solderability.
Silver and Gold	High-gloss and premium surfaces for decorative and technical purposes.
Shot Peening	Improves fatigue strength of technical springs but provides only limited or no corrosion protection.
Trowalizing/Vibratory Finishing	Removes burrs from stamped or cut parts through mechanical surface finishing.
Surface Coating	Surface coatings provide corrosion protection when non-corrosion-resistant materials are used. Additionally, they can enhance the functional or aesthetic properties of the spring (e.g., sliding layers, etc.).

If the surface treatment you require is not listed above, please do not hesitate to contact us

Our spectrum ranges from progressive tools for series parts to bending dies for individual parts. We use tool steels, PM steels, and carbide as materials. Our state-of-the-art grinding, EDM, and milling machines enable us to mill workpieces up to 800 mm x 500 mm x 400 mm or erode workpieces with maximum dimensions of 600 mm x 400 mm x 300 mm. If required, active elements can be coated to extend their service life.

We obtain the necessary production data from your CAD files (STP, IGS, DWG, DXF), sketches, or samples. Upon request, we are also happy to take over the design implementation for you.