Thermotech - Shaping New Frontiers in Heat Processing

• Mark K. HemsathVice President
  

• Thermotech Industries, Inc.

Processing with Thermotech FurnacesThe Batch Experts

• Bell Annealing of Strip, Wire and Rod Coils

• Heat Treating in Atmosphere with Vacuum Purging 

Bell Annealing with Hydrogen3%-100% H2

• Faster Heating (depending upon heat input availability)

• More Uniform Product (+/- 3.5°F)

• Much Faster Cooling (up to 2 times)

• Cleaner Surface

• Reduction in Decarburization

• More Expensive Equipment Costs (25-50%) and Installation Costs

HydrogenFaster Heating

• Furnace Design Limits Heat Input - Difficult to double input

• Due to Initial Nitrogen Purge, Benefits not immediate

• Soak Time can be less - Provided no Metallurgical Limits Exist

Hydrogen Bell Annealer

Hydrogen Bell Annealer

Air/Water Cooling Bell

More Uniform Product

• Coils Heat more Uniformly

• Final Uniformity is easier (shorter soaks)

• Better Uniformity can be achieved - New Product Grades obtainable

Better, Clean Product

• Hydrogen reduces oxides

• Hydrogen accelerates oil removal

• Hydrogen limits decarburization due to water vapor

ExampleStrip coils, 62”OD, 26” Wide, 70,000 lbs.

• 9 hrs
  

• 19 hrs
  

• 28 hrs.
  

• Heat Time
  

CoolingStrip coils, 62”OD, 26” Wide, 70,000 lbs.

• 5 hrs to 700°F
  

• Water on
  

• 9 hrs to 200°F
  

• 14 hrs cooling
  

• 25-30 hrs with Nitrogen
  

Customer Has Since Reduced Soak Time

• Was at least 19 hours

• Is now around 14 hours

• Metallurgical requirements limit reduction further on certain grades

• Some products have cut soak time in half

Cooling is Faster

• Cooling is dependent on heat removal (Cooler)

• Hydrogen makes coil much more conductive

• High Convection removes heat from coil faces

• High Convection transfers heat to inner cover walls

• External water cooling removes heat from inner cover

High HydrogenCost Comparison

• Production can be close to 100% higher with very large, dense coils (I.e. 78” OD, 60” Wide steel) and higher stacks

• Operating costs are comparable to Nitrogen - Need for oil removal increases costs

• Installation costs are higher, Capital Costs Higher

• Electrical consumption for internal convection is lower - Lighter Gas

Vacuum Annealing with Convection Heating

• Gas-Fired
  

• Can Use Hydrogen

• Can be Electrically

• Heated

Future of Gas Fired Vacuum

• Workhorse below 1950°F

• High Convection Atmosphere Processing, I.e. Nitrogen and Hydrogen

• Hydrogen for Cooling

• Batch means Quality

• Sophisticated Controls

Large Heat Treat Loads Require High Input, High Convection

Large Heat Treat Loads Require Hydrogen for Heating and Cooling

Smaller Heat Treat Loads Require Hydrogen for Brightness and Quenching

Repeatable Processing Requires Sophisticated Computer Control

Hydrogen Processing Requires Sophisticated Computer Control

PLC and Wonderware for Advanced Control

We Build

We Deliver

Fast Cooling - The Future of Hydrogen Processing