TopTech, a premier TMT bar manufacturer in West Bengal, has received quality certifications from Jadavpur University and National Test House Kolkata for its products. The certifications stand a testimony to the quality of the products manufactured by the company.
TopTech’s products were tested on various physical and chemical parameters and all of them were found to be perfect. The parameters were mass/length, tensile strength, elongation, total elongation at max force, bend test, rebend test, percentage of carbon, sulphur, phosphorus along with sulphur and phosphorus combined.
Tensile, elongation, bending and rebending properties play a crucial role in determining the robustness of a TMT bar in challenging conditions. Similarly, presence of carbon, sulphur, phosphorus too determines the purity of a bar.
Here are the various certifications received by the firm:
NTH Test Certificate for 8 & 10 mm
| Parameters | Observed Value | Limit | |
| 8 mm | 10 mm | ||
| Mass/Length (kg/m) | 0.366 | 0.583 | 8mm-0.363; 10mm-0.568 Min. |
| 0.2 % Proof Stress/ Yield Stress (N/mm2) | 590.0 | 606.0 | Min 500.0 |
| Tensile Strength (N/mm2 | 674.0 | 691.0 | Min 565.0 |
| Elongation (%) | 20.0 | 24.0 | Min 16.0 |
| Total Elongation at max force (%) | 7.5 | 8.0 | Min 5.0 |
| %C by mass | 0.21 | 0.21 | Max 0.25 |
| %S by mass | 0.030 | 0.029 | Max 0.040 |
| %P by mass | 0.024 | 0.026 | Max 0.040 |
| % (S+P) by mass | 0.054 | 0.055 | Max 0.075 |
| Bend Test (Mandrel Dia:3D of Nominal size) | Satisfactory | Satisfactory | No rupture or cracks visible on the bend portion. |
| Rebend Test (Mandrel Dia:4D of Nominal size) | Satisfactory | Satisfactory | No rupture or cracks visible on the bend portion. |
NTH Test Certificate for 12 & 16 mm
| Parameters | Observed Value | Limit | |
| 12 mm | 16 mm | ||
| Mass/Length (kg/m) | 0.852 | 1.565 | 8mm-0.835; 10mm-1.485 Min. |
| 0.2 % Proof Stress/ Yield Stress (N/mm2) | 543.0 | 560.0 | Min 500.0 |
| Tensile Strength (N/mm2 | 631.0 | 656.0 | Min 565.0 |
| Elongation (%) | 25.0 | 25.0 | Min 16.0 |
| Total Elongation at max force (%) | 8.0 | 8.5 | Min 5.0 |
| %C by mass | 0.20 | 0.21 | Max 0.25 |
| %S by mass | 0.026 | 0.032 | Max 0.040 |
| %P by mass | 0.028 | 0.026 | Max 0.040 |
| % (S+P) by mass | 0.054 | 0.058 | Max 0.075 |
| Bend Test (Mandrel Dia:3D of Nominal size) | Satisfactory | Satisfactory | No rupture or cracks visible on the bend portion. |
| Rebend Test (Mandrel Dia:6D of Nominal size) | Satisfactory | Satisfactory | No rupture or cracks visible on the bend portion. |
Test Report from Jadavpur University for 8,10,12 & 16 mm
| TMT Bar Dia (mm) | Unit/Wt (Kg/M) – Value Obtained | Unit/Wt (Kg/M) Standard Obtained | Tensile Strength (N/mm2)- Value Obtained | 0.2 % Proof Stress/Yield Stress (N/mm2) – Value Obtained | Elongation (%) – Value Obtained | Bend & Re-bend Test |
| 08 | 0.380 | 0.395 | 625 | 573 | 22.50 | OK |
| 10 | 0.607 | 0.617 | 668 | 624 | 21.67 | OK |
| 12 | 0.857 | 0.888 | 642 | 535 | 25.00 | OK |
| 16 | 1.558 | 1.580 | 657 | 557 | 18.75 | OK |
The permissible limit for 0.2% Proof stress/Yield stress (N/mm2) was 500, tensile strength (N/mm2) was 565 and Elongation (%) was 16.00. Bending and re-bending test for each bar was found to be satisfactory without any rupture or cracks on the surface of the bent.
