Monitoring Defect Levels in Steel During the Manufacturing Process.

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Monitoring Defect Levels in Steel During the
Manufacturing Process.

• Iain Baillie
• Mentors Kevin Neailey (WMG)
• Steve Dixon (Physics)

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Contents

• Problem Definition
• Objectives
• Methodology
• Innovations
• The EngD Competences
• Conclusions

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Slab Casting Process Overview
Ladle
Ladle Turret
Tundish
Slab Mould
Torch Cutter
Spray Chamber
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Slabs, Blooms Billets
Slab 2030 x 305 mm
Bloom 755 x 385 mm
Billet 180 mm2
Product length is approximately 6 to 12m
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Some Typical Casting Defects
Plus Scale Oscillation Marks
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Why Use Laser-EMATs?

• Give real time feedback to concast operators.
• Be used to guarantee product quality and
  suitability for downstream Corus External
  customers.
• Reduce the amount of scarfing (yield losses etc).
• Minimise eye-ball inspection.
• Could be linked into plant quality tracking
  software.
• Validate models.
• Size products.
• Ensure no molten core!

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How to Measure Defects?

• Need to consider the environment of a continuous
  casting plant e.g. harsh, hot, dusty, machine
  vibrations.
• No off the shelf product exists.
• It would be beneficial if both surface defects
  and internal defects could be found.

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The Selection of the Optimal Technique.

• Advice was gathered from Corus research
  scientists and from steel plant technical
  personnel. No off-the-shelf technique was
  available
• A review of the literature was conducted to
  assess all the various options available that had
  the potential for use for continuous casting.
• The Laser-EMAT technique was found to be the
  most viable one, but would require significant
  refinement to reach the prototype stage.
• Laser-EMATs use ultrasonics and can therefore be
  used to find both surface and internal defects.

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Laser-EMATs

• An EMAT is an ElectroMagnetic Acoustic
  Transducer.
• It does not need any gel or water coupling as it
  is electromagnetically coupled. The EMAT can be
  positioned a few millimetres above the surface of
  the hot steel.
• Laser generates ultrasound
• EMAT probes can be used to detect it.

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What Happens When the Laser Hits?
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Fundamental Ultrasonics
The laser generates the ultrasound The EMAT
detects the ultrasound
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Laboratory Trials Moving steel (at room
temperature)
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Trolley Based Inspection
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Side view of billet being inspected
LASER
EMAT
Slot
x
Slot
EMAT
LASER
x
LASER
EMAT
Slot
x
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Moving The Steel in 2mm increments
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Moving The Steel at Constant Velocity
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Laboratory Pilot Trials Experiments to ensure
EMATs work efficiently at high temperatures.
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Water-Cooled EMAT
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Water-Cooled EMAT
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Pilot Scale Trials Moving steel (at room
temperature)
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Cold Inspection on TTC Rolling Mill
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Results from cold tests on the rolling mill
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Pilot Scale Trials Moving steel (at 800C)
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Hot Inspection on Blue Bay Rolling Mill
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Results from the hot test on the rolling mill -
800C.
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Caster Installation
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The EngD Competences

• Expert Knowledge of an Engineering Area
• Continuous Casting Process
• Laser EMAT ultrasonics
• Software control and data acquisition via LabVIEW
  software
• The appreciation of engineering and development
  culture
• Working closely with research group within
  Physics Dept at Warwick and at R,DT with Corus.
  Able to work and communicate at all levels to
  explain aims and objectives.
• MSc Modules in this area taken.
• Project and Programme Management Skills
• Wrote EU proposal (RFCS)
• Project leader and coordinator for the RFCS
  project (1M Euro) a multi-national
  collaboration with other steel companies for
  inspection techniques.
• MSc Modules in this area taken.

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The EngD Competences 2

• Teamwork and Leadership
• I work in a matrix R,DT organisation, and lead
  the Laser-EMAT project (which I am also the
  project champion for)
• MSc Modules in this area taken.
• Oral and Written Communication Skills
• Have presented the Laser-EMAT work to EU
  conferences specifically for general steel
  management audiences, dedicated casting
  conferences and for dedicated NDT conferences.
  Winner of IOM3 Lecture Competition.
• Technical Organisation Skills
• Have managed to achieve project objectives good
  design processes of equipment, software
  interpretation modelling, software design,
  practical engineering instrumentation
  experience.
• MSc Modules in this area taken.
• Financial project planning and control
• Have controlled project spending (hours spent,
  capital expenditure, sub-contractors, component
  purchases, EU exchange rates and coordinated EU
  partners forms for the project proposal and
  mid-term financial reporting)

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The EngD Competences 3

• Ability to apply skills in new and unusual
  situations
• The casting process is somewhat unique in terms
  of industrial robustness.
• Laser-EMAT technique very much the cutting edge
• Ability to seek optimal, viable solutions for
  complex engineering problems and to seek out
  relevant information sources.
• Have met with many of the experts in casting, NDT
  and laser-EMAT fields.
• Conferences
• Have produced two in-depth literature reviews
• Have worked hard to ensure prototypes are right
  first time and to ensure the experimental
  research is as rigorous as possible.
• MSc Modules in this area taken.

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Conclusions

• EMAT probes have been optimised and water-cooled.
  They can measure ultrasonic waves at
  temperatures in excess of 1000C.
• A trolley based system has been made that can
  test steel samples easily, with a high degree of
  automation.
• Software has been designed to control the laser,
  trolley system and to acquire the ultrasonic
  data.
• For the first time in the world, Laser-EMAT
  inspection has revealed a defect in hot (800C),
  as-cast steel.
• An enhanced Pilot Plant is due to be finished at
  Corus shortly and the Laser-EMAT prototype can be
  tested on this.