Case Study 6

Encon Case Study

Recuperator For Jorden Steel


- The Furnace was initially designed by OFAG, Germany.
- Rated Capacity 30 to 32 Ton/hr.
- Bull Nose Design.


- Frequent failures of the 'Roof' and 'Bull-nose' of the Furnace
- High Fuel Consumption (up to 42 ltr/ton)
- Scale loss as high as 2%
- No Auto controls
- Interrupted production


Furnace Modification
  • Except for Hearth and 2 meters of Preheating Zone the complete furnace was redesigned.
  • 'Bull Nose' was changed to 'Camel Hump' design.
  • Change in the design of the Roof Bricks and Hangers for longevity.
Combustion System
  • Soaking zone burners were retained as LAP burners
  • Heating zone burners were changed to High Velocity with their placement done on side walls for uniformty
Level 1 Automation incorporated - Automatic temperature control
  • This was achieved by placing 6 thermocouples in the furnace, 3 Thermocouples were placed in the soaking zone and 3 Thermocouples were placed in preheating zone.
  • The air to fuel ratio was governed by a combination valve.
  • The Furnace controls were divided into 6 zones - 3 in soaking zone and 3 in Preheating zone.


- SFC 32.6 ltr/Ton (earlier 42 ltr/ton)
- Scaling is down to 1%(earlier 2%)
- Continuous operations for 2 years (earlier breakdowns every 3 months)
- Uninterrupted yield of the rated capacity of 33-35 Ton/hr.

ENCON Thermal Engineers