Carbon STEEL
Delivering trusted steel solutions with unmatched quality and service across India.
Description
Carbon steel is an iron–carbon alloy where carbon is the principal alloying element, typically present in amounts up to 2.5% by weight. Other alloying elements (Mn, Si, S, P) are present in small quantities to control properties, but do not dominate the steel’s characteristics.
Popular Grades
- C45
- MS STEEL
Advantages
- Low cost and high availability.
- Good mechanical strength for most service environments.
- Excellent fabrication properties (welding, machining, forming).
Significance in the Oil & Gas Industry
Carbon steel is the most widely used material in the oil and gas sector.
Over 80% of all components (pipelines, process vessels, storage tanks, platforms, structural members, fasteners, etc.) are made from carbon steel.
Key reasons for its dominance:
Low cost compared to alloy and stainless steels
Abundant availability worldwide
Good machinability, weldability, and formability
Adequate strength and toughness for most service conditions
Because of this, design and process adjustments are often made to allow the use of carbon steels rather than switching to costlier alloys.
Classification of Carbon Steels
| Type of Carbon Steel | Carbon Content (wt%) | Typical Properties | Common Applications |
|---|---|---|---|
| Low Carbon Steel (Mild Steel) | 0.05 – 0.30 | High ductility, toughness, easy welding, and low strength | Pipelines, structural steels, tanks |
| Medium Carbon Steel | 0.30 – 0.60 | Higher strength, moderate ductility, wear resistance | Shafts, axles, gears, machinery parts |
Chemical Composition
| Grade Type | C | Mn | Si | P (max) | S (max) | Fe |
|---|---|---|---|---|---|---|
| Low Carbon Steel (Mild Steel) | 0.05 – 0.30 | 0.40 – 1.00 | 0.10 – 0.40 | 0.040 | 0.050 | Balance |
| Medium Carbon Steel | 0.30 – 0.60 | 0.60 – 1.65 | 0.10 – 0.40 | 0.040 | 0.050 | Balance |
Mechanical Properties
| Grade Type | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) | Hardness (HB) |
|---|---|---|---|---|
| Low Carbon Steel (Mild Steel) | 370 – 500 | 200 – 250 | 25 – 40 | 120 – 180 |
| Medium Carbon Steel | 550 – 700 | 300 – 450 | 15 – 25 | 170 – 240 |
Heat Treatment
| Process | Low Carbon Steel | Medium Carbon Steel | High Carbon Steel | Ultra-High Carbon Steel |
|---|---|---|---|---|
| Annealing | 870 – 910 °C, furnace cool | 840 – 890 °C, furnace cool | 800 – 850 °C, furnace cool | 750 – 800 °C, furnace cool |
| Normalizing | 890 – 940 °C, air cool | 860 – 910 °C, air cool | 830 – 870 °C, air cool | 780 – 820 °C, air cool |
| Hardening (Quenching) | Rarely used | 790 – 840 °C, water/oil quench | 760 – 820 °C, water/oil quench | 750 – 800 °C, oil quench |
| Tempering | – | 540 – 680 °C (reduce brittleness) | 150 – 650 °C (as per hardness requirement) | 150 – 400 °C (caution: brittle at higher C) |
Supply Cities
- Agra, Alwar, Ambala, Anand, Bhiwadi, Dehradun,
- Ghaziabad, Haridwar, Rudrapur, Delhi, Faridabad,
- Kanpur, Noida, Gurgaon, Manesar, Kundali,Chandigarh,
- Waluj , Vadodara, Pimpri - Chinchwad, Rajkot, Jaipur,
- Ahmedabad, Pithampur, Surat, Amravati, Vadodara,
- Indore, Bhopal, Ranchi, Jamshedpur, Howrah,Kolkata,
- Pune, Thane, Nashik, Mumbai, Navi Mumbai, Nagpur,
- Ambattur, Bangalore, Belgaum, Chittoor, Dindigul,
- Hyderabad, Ernakulam, Chennai, Secunderabad,
- Visakhapatnam, Coimbatore, Mysore, Nellore, Kochi,
- Tirupati, Nazarathpet, Kakinada, Kurnool and many
Conclusion
The oil and gas industry, the construction industry, and the manufacturing sector continue to depend on carbon steels, which are cheap and available, and also possess versatile characteristics. By classifying them as low carbon, medium carbon, high carbon, and ultra-high carbon, engineers can select the suitable grade of pipelines, machines, tools, or structural elements. The treatment of carbon steels enables them to offer the desired strength, hardness, ductility, toughness balance, and can, therefore, not be neglected in contemporary industrial uses.
