installed at the rolling mill.
Layout of the main equipment of the rolling mill 1700 is shown in Fig. 1.
Figure 1. Flowchart: the main equipment of the rolling mill 1700
According to the project and applicable technology, the rolling mill produces hot
rolling coils weighing up to 9 tonnes, having a thickness of 1.5-9 mm, width of 1000-
1530 mm, depending on the product mix, of steel grades from 08ps (according to
GOST 1050) to 09G2S (according to GOST 19281), S355 of all categories in
accordance with EN 10025-2 and another similar product mix limited to the tensile
strength of no more than 590 MPa.
During the production using TMCP technology, the principal difference is the low
level of chemical elements that provide for the strength properties of the rolled products
(comparison is given in Table 1).
Table 1 Comparison of the values for the products, which are manufactured
under different process conditions
Standards Technology*
Steel
grade
Values / Chemical composition
С max.,
%
Mn
max., %
Nb
max., %
V max.,
%
Ti
max., %
CЕ
max.
KV-20
min., J
EN 10025-2
AR; N
2
S355J2
0.20
1.60
-
1
-
1
-
1
0.45
27
EN 10025-4
TMCP
S355ML
0.14
1.60
0.05
0.10
0.05
0.39
47
EN 10149-2
TMCP
S355MC
0.12
1.50
0.09
0.20
0.15
-
-
* AR – hot-rolled; N – as normalized rolled; TMCP – as TMCP rolled;
1
– it is allowed to use elements;
2
– prevailing condition of the rolled products according to this standard.
Thus, the major difference of the requirements for rolled products manufactured
using TMCP is the lower level of the chemical elements in comparison with other
methods, and also the addition of microalloying elements. In total, such changes
provide for excellent complex of mechanical properties.
1 – reheating furnaces;
2 – roughing train;
3 – heat-saving shields;
4 – rotary shears;
5 – finishing train;
6 – accelerated cooling units;
7 – coilers.
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