Consistent quality testing for transparency and process reliability

• Cold heading and cold extrusion steels to EN 10263-2, 3 and 4
• Modified steels for cold heading high strength bolts up to strength class 16.9 (on request 18.9)
• Cold extrusion steels optimised for supplementary machining
• AFP steels to EN 10267 and bainitic steels to SEW 605
• Roller bearing steels to EN ISO 683-17 and optimised qualities for special bearing applications
• Spring steels to EN 10080 and also optimised spring steel qualities with non standard classification
• Chain steels for manufacturing forged or butt-welded chains
• Case hardening steels to EN 10084
• Quenched and tempered steel to EN 10083 and optimised qualities for improved through-hardening
• Ferritic/pearlitic and pearlitic steels for pre-stressing steels, tyre cord, profiled section wire for flexible pipes, and ultra-high-strength ultra-fine wires
• Hard drawing qualities to EN ISO 16120-2 – steels for technical springs and wire cable
• Basic drawing qualities and mild drawing qualities to EN ISO 16120-2 and 16120-3
• Structural steel and fine-grained steel to EN 10025-2/-3

• Drawing stock for weld metals
• Special qualities using special measures in the area of secondary steel making
• Super clean qualities with limited steel inclusions specifically in the surface area
• High-purity qualities for situations where the route via ESU and VAR is economically unattractive

• Round bloom 230, rectangular 270 x 360 or 330 x 440 mm
• Billet 150 x 150 mm
• Drawing stock 5.0 to 52 mm
• Cold-drawn wire 0.5 to 49 mm
• Wet-drawn wire 0.04 to 0.50 mm
• Surface textured wire 0.09 to 0.175 mm
• Profiled section wire from 2 to 200 mm²
• Braided wire with filament diameters up to 8 mm
• Cords with single filament diameters up to 0.5 mm

• Hot-rolled wires to DIN EN 10017
• Drawn wires to DIN EN 10278

In the rolling process we utilise the following methods:

• Stelmor cooling (fast cooling, standard cooling, active slow cooling)
• Thermomechanical rolling
• Bainitic transformations from the rolling heat
• Water cooling on the Garrett line

In the drawing shops we have a large number of other processes available according to diameter, which are performed open to air or under inert gases:

• Annealing to spheroidal cementite (+AC)
• Tempering
• Soft annealing
• Annealing to specified strength/hardness
• Lead-bath patenting
• Homogenising (>1100 °C) for segregation conditioning
• Homogenising (>550 °C) for surface transformation
• Stress relieving

We are constantly developing new solutions for surface treatments. Our ambition is to produce carbon-neutral coatings for all application scenarios. To that end we maintain close development partnerships with private and public-sector research establishments.

For drawing stock we offer the following options for best-possible surface qualities:

• Hard-rolled for mechanical or chemical de-scaling
• Pickled
• Phosphatised
• Phosphate-free
• Limed, soaped, polymer-coated

To ensure the quality of the drawing stock surface, we maintain a fully automated high-rise racking warehouse. In that way we can reduce the risk of mechanical damage, corrosion spots, securing and simplifying transport logistics.

The range of drawn wires is diverse and follows the requirements of subsequent wire use:

• Pickled
• Phosphatised
• Phosphate-free
• Limed, soaped, polymer-coated
• Copper, brass, nickel and zinc-based galvanic and chemical coatings
• Hot-dip galvanising

• Format: 1 kg - 3000 kg
• Packing: all types, including special solutions for
  extreme environments and custom delivery formats

• ISO 9001 (Quality Management)
• ISO 14001 (Environmental Management)
• OHSAS 18001 (Occupational Health & Safety)
• ISO/IEC 17025 (Testing Laboratories)
• ISO 45001 (Health & Safety Management)
• ISO 50001 (Energy Management)
• EMAS III (EU Environmental Audit) audited
• For our customers in the automotive sector, we are certified to IATF 16949 (automotive industry quality management systems)

In addition, we hold many other specific individual certificates (for particular products or countries), e.g. GL, DNV, etc.

In this particular area we rely on the use of optical testing methods and artificial intelligence. It starts right from the rolling of the billets, continues with the precise measurement of the billet geometry in the hot-rolling mill, the documentation of the surface condition and the optical testing along the production line. At critical points, the system is supported by thermography or eddy current testing.

Methods employed along the value-added chain include:

• Thermography
• Eddy-current testing
• Optical testing assisted by AI
• Acoustic testing assisted by AI

Internal flaw tests are carried out on billets to verify core density and absence of cracking.

• In-line ultrasonic testing
• Ultrasound immersion testing for critical materials
• Manual testing for final verification

For dimension checks we rely on laser and optical spectrometry. The testing parameters applied are diameter, ovality, angular offset in the case of rectangular cross-sections, and evenness in the case of surface-textured products.

To be able to offer the highest standards of laboratory testing, we have established centralised, accredited (EN ISO/IEC 17025) laboratories which are available both for production approvals and stress-proof test results in research programmes.

The list of laboratory tests covers a wide range:

• Optical microscopy examinations (available at all our sites)
• Tensile tests (available at all our sites)
• Scanning electron microscope examinations for microstructure assessments, phase analyses, element analyses, lattice orientation, slag charts and much more
• Dilatometer examinations as the basis for optimised heat treatments
• Physical testing on a thermal-mechanical testing device (temperature, tension/compression. torsion)
• And much more

The operational optimum is constantly sought by round robin testing for all testing equipment. Comparative testing with the nearby universities provides a juxtapose with other state-of-the-art technologies.