Manufacturing systems and services for the series production of metallic bipolar plates for fuel cells and electrolyzers.
Gräbener Maschinentechnik GmbH & Co. KG
Netphen-Werthenbach (headquarters)New on Amplifa
About Graebener Bipolar Plate Technologies
Gräbener Maschinentechnik, with its business unit Graebener® Bipolar Plate Technologies, develops and manufactures in Netphen systems and production lines for the manufacture of metallic single and bipolar plates – the heart of fuel cells and electrolyzers. Founded in 1921, this medium-sized mechanical engineering company supports customers from plate design analysis and CAD engineering through toolmaking to single systems for forming, cutting, welding and straightening, as well as scalable series production lines from coil to finished plate. In its own production laboratory, prototypes and small series of up to 50,000 parts per year are produced; materials from a foil thickness of 25 µm and plate sizes up to 2,500 cm² are processed. In addition, a stack press supports the technical testing of fuel cell and electrolysis stacks. Customers come from hydrogen technology, automotive as well as the steel, fertilizer and gas industries; over 100 plate designs have been implemented, and more than 125,000 plates have been manufactured on the company's systems.
- Site
- Netphen
- Processes
- Forming (metallic single/bipolar plates, hydroforming press with sandwich tool, multiple, Laser melt cutting, Laser scanner welding, Contactless straightening (elimination of stress-induced curvatures), Measuring/testing by means of cross-section preparation, Leak testing (leakage test, 100% tightness testing), Coating, Prototyping/verification of the manufacturability of plate designs
- Materials
- Stainless steel, Titanium, Copper, Clad materials, Pre-coated materials, Metal foil from 25 µm thickness, Hydroforming, Laser melt cutting
- Founded
- 1921
- Industries
- Hydrogen (fuel cells/electrolysis), Automotive, Steel, fertilizer and gas industry, Shipbuilding, Hydroforming, Tubes
- 01
Engineering (plate design analysis, CAD implementation, process consulting)
- 02
Tool engineering
- 03
Prototyping in the production laboratory
- 04
Forming (hydroforming press with sandwich tool)
- 05
Laser melt cutting
- 06
Laser scanner welding
- 07
Contactless straightening
- 08
Coating
- 09
Measuring/testing and leak testing
- 10
Construction of scalable production lines including assembly, commissioning and
Materials and processes
Stainless steel
Most common material for metallic single and bipolar plates in fuel cells.
Titanium
Used primarily for plates in PEM electrolysis.
Copper
For bipolar plates with special requirements regarding electrical conductivity.
Clad materials
Combine mechanical and corrosion-protective properties in one plate.
Pre-coated materials
Processing of fuel-cell-suitable base materials verified in the PreCoat project.
Hydroforming
Forming process with a sandwich tool that produces several plates per stroke.
Laser melt cutting
Precise cutting without tool wear, even with complex structures.
Laser scanner welding
Deflectable laser optics enable high speeds and the smallest spot sizes in channel structures.
Contactless straightening
Eliminates stress-induced curvatures without affecting surface and geometry.
Locations
Netphen-Werthenbach (Bhf.)
DEHeadquarters, engineering, production systems engineering and production laboratory
- Part weight / size
- Plates up to 2,500 cm²
- Lot size
- Smallest lot sizes up to small series of 50,000 parts/year
- Materials
- Stainless steel, titanium, copper, clad and pre-coated materials from 25 µm
- Hydroforming press with sandwich tool
- Cutting system (laser melt cutting)
- Welding system (laser scanner technology)
- Straightening system (contactless)
- Stack press
- Scalable production lines from coil to finished plate
Components
Inside the production
Industries
Processes & technical limits
| Processes | Tolerance | Max. part | Weight | Lot size | Materials |
|---|---|---|---|---|---|
| Forming (metallic single/bipolar plates, hydroforming press with sandwich tool, multipleForming | – | Plate sizes up to 2,500 cm² | – | smallest lot sizes – Small series up to 50,000 parts/year | Stainless steel, Titanium, Copper, Clad materials, Pre-coated materials, Foil from 25 µm |
| Laser melt cuttingMachining | – | – | – | – | Stainless steel, Titanium, Copper, Clad materials, Pre-coated materials |
| Laser scanner weldingJoining | – | – | – | – | Stainless steel, Titanium, Copper |
| Contactless straightening (elimination of stress-induced curvatures)Forming | – | – | – | – | Stainless steel, Titanium |
| Measuring/testing by means of cross-section preparationTesting | – | – | – | – | – |
| Leak testing (leakage test, 100% tightness testing)Testing | – | – | – | – | – |
| CoatingSurface | – | – | – | – | – |
| Prototyping/verification of the manufacturability of plate designsEngineering | – | up to 2,500 cm² | – | – | Stainless steel, Titanium, Copper |
| Plate design analysis, CAD modeling, systems engineering, process consultingEngineering | – | – | – | – | – |
| Technical testing of fuel cell/electrolysis stacks (stack press)Testing | – | – | – | – | – |
6 Anlagen & Maschinen
| Machine | Manufacturer / model | Quantity | Working area | Year built | Site |
|---|---|---|---|---|---|
| Hydroforming press (forming press) with sandwich tool | Graebener | – | Plate sizes up to 2,500 cm², material from 25 µm foil thickness | – | Netphen / production laboratory |
| Cutting system (laser melt cutting) | Graebener | – | – | – | Netphen / production laboratory |
| Welding system (laser scanner technology) | Graebener | – | – | – | Netphen / production laboratory |
| Straightening system (contactless) | Graebener | – | – | – | Netphen / production laboratory |
| Stack press | Graebener | – | – | – | Netphen |
| Scalable production lines for bipolar plates (from coil to finished plate) | Graebener | – | – | – | – |
Additional services
Reference customers
History
- 1921
Company founded; since then metal processing and mechanical engineering
- 2014
Completion of project BREEZE!: market readiness of the system technology demonstrated; 30 kW range extender for the Fiat 500 with metallic bipolar plates from Graebener