2. Hot Rolling Mill
Fig. 16 – General layout of a large capacity hot strip mill (Sollac Fos sur Mer)

3. Dofasco #2 Hot Strip Mill
Coilers
Runout Table
Finishing Mill
Rougher
Reheat Furnaces
Strip
mm thick
mm wide
Transfer Bar
~30 mm
Slab
216 mm

4. Advanced Hot Mills

5. Gallatin Steel (CSP)

6. Thin Strip Casting

7. Figure 3.8 Walking beam furnace at SSAB, Domnarvet.
Reheating Furnaces
Figure 3.8 Walking beam furnace at SSAB, Domnarvet.
Figure 3.9 Evaporative cooling system on walking-beam furnace at SSAB, Domnarvet.

8. Figure 3.7 Sketches illustrating operation of a walking-beam furnace
Reheating Furnaces
Figure 3.7 Sketches illustrating operation of a walking-beam furnace

9. Slab Reheating Figure 3.5 Heating time as a function of slab thickness
Figure 3.6 Furnace heating capacity as a function of slab thickness

10. Table 3.3 Basic Data For 68-Inch Hot Strip Mill
Hot Mill Layout
Table 3.3 Basic Data For 68-Inch Hot Strip Mill
Stand or Unit
Stand Type
Roll Sizes (in.)
Speed (fpm)
Drive Power (hp)
Remarks
Vertical edger
First rougher
2-hi 46
48 x 68
250
220
1500 ac
4500 ac
Back-passing provision
hydraulic roll changing
Second rougher with 33 inch vertical edger
Space available for future back passing
Third rougher with 33 inch vertical edger
4-hi
42 & 56 x 68
330
8000 ac
Gear drive and pinion stand. Gear type spindles and hydraulic roll changer
Fourth rougher
dc drive for speed
Foundations only for future installation
Fifth rougher
Crop shear
Scale breaker
658
250/500
Six finishing stands (F1-F6)
28 & 56 x 68
3240 out of F6
7000 (each)
Rapid work-roll changing electric loopers, AGC
Seventh stand
3740 out of F7
Future installation
Two X-ray gages
Width gage
Runout table
Two coilers
500 each
About 500 ft long 3-blocker roll type

11. Roll Stack
Bending system
Four-high mill

12. 4 high mill system in Mae West design
Mill Stand
4 high mill system in Mae West design

13. Mill Housing

14. Figure No. 3 Mill Stand Elevation

15. Strip Edge Drop Edge drop compensation
Elastic deformation of roll assembly under rolling condition

16. Strip Shape
Shape Calculation

17. Continuously Variable Crown (CVC)
CVC Crown Control
Continuously Variable Crown (CVC)

18. Figure 7.1 Construction of PC mill (Tsukamoto and Matsumoto)
Pair Cross Mill
Figure 7.1 Construction of PC mill (Tsukamoto and Matsumoto)

19. Physical Forces within the Roll Bite
Roll Bite Forces
Physical Forces within the Roll Bite

20. Sims Diagram

21. Typical layout and material flow of a cold rolling mill
Cold Mill Layout
Typical layout and material flow of a cold rolling mill

22. Table 6.3 Design Characteristics of a Modern Pickling Line
DIMENSIONS
LINE SPEEDS
Strip thickness: 1 to 6 mm
Strip width 1000 to 1850 mm
Coil OD maximum: 2200 mm
Coil ID entry: 620 to 850 mm
Coil ID exit: 600 mm
Coil weight: 39 tons
Entry speed: 600 m/min
Speed in pickling: 220 m/min
Exit speed: 350 m/min
Acceleration time: 10 Seconds
Emergency stop: 5 seconds
Line length: 200 meters

23. 4-high reversing cold rolling and temper mill
Cold Rolling Mill
4-high reversing cold rolling and temper mill

24. Main equipment of tandem cold mill

25. Thickness control for tandem cold rolling mill
Gauge Control
Thickness control for tandem cold rolling mill

26. Cleaning Line
Figure 23.1 Schematic arrangement of a typical electrolytic cleaning line

27. Figure 23.12 Time-temperature cycles
Batch Annealing
Figure Single-stack coil-annealing furnace with base, fan, inner cover and fan coils with convectors (Rao et al.).
Figure Time-temperature cycles

28. AlN Precipitation During Coiling
Role of AlN precipitation during subsequent annealing:
Batch annealing: AlN precipitation during annealing preferred
Continuous annealing: AlN precipitation during coiling preferred

29. Continuous Annealing

30. Continuous Annealing
Table Fukuyama Works No. 1 Continuous Annealing Line*
Material
Thickness
Width
Entry and delivery coils
ID and OD
Weight
Line speed (cold rolled strip)
Entry section
Furnace section
Delivery section
Line speed (black plate for tinning)
Capacity
Cold rolled strip
Black plate for tinning
Cold rolled mild steel strip
0.15 to 0.8 mm
457 to 1067 mm
508 x 2440 mm
32,000 kg max
188 m/min
150 m/min
572 m/min
457 m/min
24 tonnes/hr (0.6 mm x 800 mm)
44 tonnes/hr (0.254 mm x 813mm)
Table Mechanical Properties, 0.8 mm Strip
Continuous annealing
Batch annealing
Yield stress (kg/mm2)
Tensile strength (kg/mm2)
Elongation (%)
Erichscn value (mm)
r-value
CCV, mm
22.0
32.9
45.0
10.1
1.51
37.8
22.2
32.0
46.5
10.4
1.26
37.9
Table Properties of soft tinplate, 0.32 mm thick
Continuous annealing
Batch annealing
Yield stress (kg/mm2)
Yield point elongation (%)
Tensile strength (kg/mm2)
Elongation (%)
Erichscn value (mm)
Hardness (hr 30T)
ATC (µA/cm2)
IYV (µg/3 in2)
PLT (s)
28.1
2.1
34.3
36.6
8.9
54.8
0.02
3.5 3
33.0
5.4
36.4
37.0
9.3
55.0
0.07
7.7 5
*Note: Capacity for cold sheet can be increased through additional heat input of the accelerated over-aging zone.

31. Microstructure Evolution During Cold Rolling
Deformation
Work hardening
Ferrite (a) / Pearlite

32. Microstructure Evolution During Annealing
Preheat
Soaking
Cooling
Over-aging
Final Cooling
Recovery
Recrystallization
Grain growth

33. Figure 24.3 Yield strength variation with elongation
Temper Rolling
Figure 24.3 Yield strength variation with elongation
Figure 24.2 Stress-strain curves: (a) box-annealed rimmed deep-drawing steel; (b) diagram illustrating offset method for determining yield strength

34. Temper Mill
Figure Layout of temper and processing line (TPL) facility (Fujiwara et al.).

35. Fig. 18 - Layout of an electrolytic tinning line

36. Hot Dip Galvanizing General characteristics
Material:
cold rolled mild steel strip
Entry YS 800 MPa maxi-200 MPa mini
Exit YS 140 MPa mini
Strip width:
Mini 750 mm
Maxi 1850 mm
Strip thickness:
Mini 0.30 mm
Maxi 1.6 mm (2 mm with allowance)
Coil dimension Entry Exit
Line speed
Engagement 0 to 60 m/mm
Entry 20 to 200 m/mm (240)
Treatment 40 to 150 m/mm (180)
Exit 20 to 200 m/mm (240)
Commissioned in 1991
Outside diameter mini 1200 mm mini 1200 mm
maxi 2100 mm maxi 2100 mm
Inside diameter mm mm
Weight kg kg
Fig. 4 - Schematic layout of a hot dip galvanizing line