Our Products

stainless and mar­tensitic strips 0.08 - 0.8 mm

Hardening

of strip steel and flat­wire of 2 - 30 mm width

Cutting

of steel, aluminium, copper and brass strips

Production

cutting, deburring, hardening and lacquering

Production

Innovative machines for strip steel production. Developed by Cobra Engineering.

Slittering Line

Circular Shears

High performance slittering line with 10 coiling units and integrated deburring
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Hardening

H-Hardening Plant

Hardening and heat treatment of strips with inert gas atmosphere up to 1200 °C
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Edges and Surfaces

Polishing Plant

Edge and surface polishing starting from 2 mm width
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Lacquering

Lacquering Plant

Continous bilateral strip coating for up to 30 mm width
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Cambering

Profiling machine

Cold profiling of strips for up to 0.2 mm width
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Spooling

High Performance Spooling

Innovative coiling for up to 1000 kg coil weight
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Strip Steel Coil Calculator

Use our Cobra Coil Calculator to get you coil weight and length easily.

mm x mm  ≙ g/m

Enter strip width and thickness

kg   ≙

Resulting length

Ø inner mm   Ø outer mm

Inner and outer diameter of single coil

Coil weight: kg

Resulting weight of single coil

in. x in. ≙ oz./ft.

Enter strip width and thickness

lb.  ≙

Resulting length

Ø inner in.   Ø outer in.

Inner and outer diameter of single coil

Coil weight: lb.

Resulting weight of single coil

Imperial units
Auto run

Also check out our handy Camber Calculator to get the non-linear deviation of straightness for any strip steel length.

Specifications

Our products for your application.

  • Width: 2 – 30 mm
  • Thickness: 0.06 – 0.8 mm

Width tolerance

  • Standard tolerance: + 0.1 – 0.15 mm
  • Extended tolerance: ± 0.02 mm

Thickness tolerance

  • In accordance with EN 10140
  • Optional extended tolerances T3, T4

Surface

  • bright hardened
  • yellow/blue tempered
  • phosphate treated, lacquered
  • bright polished
  • brushed

Edges

  • neat cut
  • deburred
  • rounded

Cold rolled and und hardened strip steel (stainless)

  • Tensile strength 500 – 1000 N/mm2 unhardened carbon steel
  • Tensile strength 1000 – 2100 N/mm2 for hardened spring steel and stainless tape measure strips
  • Tensile strength 500 – 2100 N/mm2 für stainless strips

Flatness

  • < 0.02 mm / 10 mm width

Straightness

  • < 0.8 mm / 1000 mm
  • Extended tolerance: 0.3 mm / 1000 mm

Hardened steel

No.DINAISI
1.1231Ck 671070
1.1248Ck 751075
1.1274Ck 1011095

Stainless martensitic steel

No.DINAISI
1.4021X 20 Cr 13416
1.4028X 30 Cr 13420
1.4034X 46 Cr 13420

Austenitic stainless steel

No.DINAISI
1.4310X 10 Cr Ni 18-8301
1.4401X 5 Cr Ni Mo 17122316
1.4301X 5 Cr Ni 18-10304
1.4571X6 Cr Ni Mo Ti 17122 
1.4541X6 Cr Ni Ti 18-10321
1.4404X2 Cr Ni Mo 17132316 L
1.4372  

Single coils

  • Inner diameter: 230 – 400 mm
  • Outer diameter: 600 – 800 mm

Coil winding

  • Inner diameter: 300 mm, 400 mm or 500 mm
  • Maximum weight: 1000 kg

Bars / pieces

  • Length: 2 – 2000 mm

References

Our customers rely on Cobra Bandstahl.

Contact

Your way to the most innovative solutions for high performance strip steel.

Contact details

Cobra Bandstahl GmbH
Kinzigstr. 12
63607 Wächtersbach

phone +49 (0) 6053 30 16
telefax +49 (0) 6053 30 19

web cobra-bandstahl.de
mail info@cobra-bandstahl.de

Tensile Test (DIN EN 10002)

The tensile test is a standard procedure in material testing. It serves to test the material behavior at uniaxial, constant pull.

In this test, the steel strip is fixed to an all-purpose testing machine and is pulled until it breaks. This way the tensile strength or the maximum load subject to the cross-section area is determined. Once the tensile strength is determined, we know at what point there will be material failure and the steel strip will break.

Vicker's Hardness Test

With the Vicker’s Hardness Test (according to DIN EN ISO 6507-1), the tip of a diamond of quadrangular pyramid shape with a 136° ankle is pressed into the material with a predetermined force. This test is for thin, small pieces and materials with surface finishing.

With a microscope it is possible to determine the length of the diagonal of the indentation and thus to calculate the surface of the indentation.

Looptest

The Looptest is a simple but effective method for evalutating the ductility of quenched steel strips. To perform the testing, a steel loop is pulled through defined slots.

“Breaks at x mm.”

Optionally, a vice test can be performed. The looped strip is clamped in a vice with measuring scale. The “bend value” is defined as the threshold where the first fissures occur in the strip. 

Straightness Test

The camber deviation is determined by examining the light diffraction of a sample strip on a test bench. Unfortunately, this method only enabled us to make a qualitative statement about straightness. 

To evaluate the camber deviation quantitatively, our digital measuring microscope is used.