After rolling, the coils were processed at the accelerated cooling unit, see Fig. 1.
Actual thermomechanical parameters of the pilot batch production are shown in
Table 5.
Table 5. Actual thermomechanical values of the rolling process
Parameter
Unit
Parameter value
Slab reheat temperature
°C
1260-1280
Heat time
hours-minutes
2-12
Rolling temperature behind the stand 4а
°C
1105-1117
Rolling temperature behind the stand 10
°C
880-887
Coiling temperature
°C
623-644
Number of sections, which are used for accelerated cooling
pcs.
14
Cooling rate
°C/s
60.2
Comparison of the target and actual data according to the average metal
temperatures behind the stands 4a, 10, and coiling temperatures are shown in Fig. 3.
Figure 3. Comparison of target and actual metal temperatures based on the
process operations
In fact, the obtained thermomechanical parameters are slightly higher than the
target ones, which is associated with the regulation of parameters during the rolling,
and also the technology refinement. It is worth mentioning that in order to obtain the
necessary mechanical properties, increase in the rolling finishing temperature at the
stand 10 and the coiling temperature were compensated by using maximum number of
cooling sections, which has contributed to increase in the cooling rate of the rolled
products.
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