The production of TMT rebars involve a combination of plastic deformation of steel in austenitic stage followed by quenching and further tempering. The process controls at each critical operation ensure uniform properties in each rebar and provides the TMT rebars with a soft ferrite and pearlite fine grained core, a strong and tough tempered martensite layer imparting it with high ductility as well as strength thus making it ideal for high rises, dams, bridges, individual houses and any critical structures where high yield strength is required without compromising on the elongation properties.
The TMT rebars are conforming to the latest BIS-1786: 2008 specifications and are available in Fe 500, Fe 500D in normal, where Fe 500D grade is highly suitable for seismic prone areas.
Comparison of BMM 500D and ISI Standards
MECHANICAL PROPERTIES |
BIS : 1786 |
BMM STANDARDS |
GRADE |
Fe 500D |
Fe 500D |
Proof / Yield strength N/mm2 (min) |
500 |
540 |
Tensile strengthN/mm2 (min) |
565 |
625 |
Elongation % (min) |
16% |
16 |
Total Elongation % (min) |
5% |
– |
Bend Test (upto 20mm) |
3D |
3D |
Bend Test (above 20mm) |
4D |
4D |
Re Bend test (upto 10mm) |
4D |
4D |
Re Bend test (above 10mm) |
6D |
6D |
Sizes & Optimum weight of BMM TMT 500
Type |
Section |
BIS Standards |
BMM Standards |
TMT |
Size in mm |
Area in Cm2 |
Kg/mtr |
Area in Cm2 |
Kg/mtr |
8 |
50.3 |
0.395 |
48.54 |
0.381 |
10 |
78.6 |
0.617 |
75.92 |
0.596 |
12 |
113.1 |
0.888 |
110.32 |
0.866 |
16 |
201.2 |
1.58 |
196.05 |
1.539 |
20 |
314.3 |
2.47 |
309.43 |
2.429 |
25 |
491.1 |
3.85 |
483.57 |
3.796 |
32 |
804.6 |
6.31 |
792.23 |
6.219 |
40 |
1018.3 |
7.99 |
982.17 |
7.71 |
FLATS |
1 |
spring steel flats |
EN45, EN45A, 55 Si 7, 65 Si 7, SUP9, SUP11A |