Exit
 

Heat-Treating and Metal Finishing Analyzers

Gas analyzers can be used for monitoring atmosphere gases and flue gases in steel finishing and heat treating furnaces in steel mills.

After molten steel is produced by the melt shop, it usually then requires shaping and finishing in rolling mills, bar mills, blooming mills, wire mills, etc. Gas analysis in these mills are generally classified as being either flue gases or atmosphere gases. Many mills also require gas monitoring of the ambient air around furnaces for safety purposes.

Flue Gas

Molten steel may be directly cast into slabs or continuously rolled out into strips. The slabs and strips may be further processed into other finished products such as bars, billets, beams, or wire. The slabs may be stored and processed later, while continuous strip lines produce a finished coil. In either case, a reheat furnace will be required to bring the steel back up to even temperature for finishing. An even temperature profile in the steel is desirable to promote even rolling and finishing. The steel needs to ‘soak’ in the heat. Re-heat furnaces are therefore also frequently called heat soak furnaces.

rolling-mills

The heat is usually produced by burning natural gas through a series of isolated burners in the furnace. The flames are contained in a series of tubes in the furnace and are isolated from the furnace atmosphere. The heating is indirect because it radiates out the tubes and into the furnace. Analysis of flue gas emerging from the tubes is used to determine if the fuel is being efficiently and safely burned. It is also useful in determining if a tube has cracked and is leaking into the furnace atmosphere. A gas analyzer will provide this measurement. The NOVA 7200 Series will provide continuous analysis of common flue gases such as oxygen, carbon monoxide, carbon dioxide, nitrogen dioxide, and others.

Nova 7200 Series Continuous Flue Gas Analyzers

  • Continuous analysis of flue gases
  • O2 / CO / CO2 / NO
  • Long-life sensors / detectors
  • Sample conditioning built into analyzer cabinet
  • Microprocessor control with push button calibration
  • Easy-to-maintain modular layouts
  • Built-in sample motivation included
  • 4-20mA recorder outputs

re-heat-furnace
reheat-furns

Atmosphere Gases

Coils or strips produced by the finishing mills may be further processed into specialty steel products with specific finishes, sizes, or hardness. One example is annealing. After rolling operations, the steel will be work-hardened and will need to be annealed to restore the desired ductility. Annealing furnaces require heat and a specific operating atmosphere to remove the carbon from the steel. Carburizing furnaces use heat and specific atmospheres to add carbon and hardness to manufactured steel parts. The specific atmosphere will depend on the type of heat treating. Heat treat furnaces are different from re-heat in that the produced atmosphere is in direct contact with the steel instead of being isolated.

Heat treat atmospheres may be comprised of oxygen, carbon monoxide, carbon dioxide, hydrogen, or methane. The specific atmosphere will depend on the type of heat treating. The NOVA 7900 Series can be configured to provide measurement of all of these gases in the single instrument.

annealing-furns2

 

NOVA 7900 Series Heat Treat Gas Analyzer

  • Continuous analysis of atmosphere gases
  • O2 / CO / CO2 / CH4 / H2 / Dew Point available
  • Long-life sensors / detectors
  • Sample conditioning built into analyzer cabinet
  • Microprocessor control with push button calibration
  • Easy-to-maintain modular layouts
  • Built-in sample motivation included

 

bell-anealling3

Safety Monitoring

The atmospheres and products of combustion associated with many steel-making operations contain toxic gases that can cause injury or death to nearby staff. This is especially the case in confined spaces and areas where gases are stored in tanks and cylinders. A gas may be directly harmful because of its chemistry, or it may be indirectly harmful because it displaces oxygen.

The NOVA 500 Series Monitors can monitor ambient air for various gases. A visible and audible alarm will alert nearby staff that a potentially dangerous condition exists.

NOVA 500 Series Ambient Air Monitors

  • Continuous monitoring of ambient air
  • O2 deficiency, CO, CO2 and others available
  • Long-life sensors / detectors
  • Sensors are easy to replace when needed
  • Built-in sample motivation included if needed
  • 4-20mA recorder outputs
  • Two-point alarm package available with horn and strobe light

Personnel-Safety

Ready for the next step?  Please contact our Sales team for more information or view products here.

 

NOVA-+-TNOVA2

Top
View Our
Product Catalog
Have a question?
Contact Us
Ready to get started?
Request Quote