Filiz Steel stands out as a premier manufacturer and reliable supplier located in Istanbul, Turkey, with a focus on high-quality ST 35 and ST 35.8 tubing. The company prides itself on its dedication to precision engineering, top-notch materials, and adherence to international quality standards. Filiz Steel caters to a wide array of industries, including energy, automotive, construction, and machinery. They provide both seamless and welded tubing solutions customized to meet client needs, ensuring dependable performance even in the most demanding applications. With a strong emphasis on innovation, customer satisfaction, and global distribution, Filiz Steel has earned a solid reputation as a trustworthy partner in the steel tubing market throughout Europe, the Middle East, and beyond.
ST 35 and ST 35.8 tubing are low-carbon steel grades that are frequently utilized for seamless pressure pipes. These materials typically contain up to 0.17% carbon, 0.35–0.70% manganese, along with trace amounts of phosphorus and sulfur. They are known for their excellent weldability and machinability. In terms of mechanical properties, they boast a tensile strength range of 480–640 MPa and a yield strength of around 255 MPa. With a minimum elongation of 25%, the tubing showcases impressive ductility and toughness. ST 35.8 is often normalized to boost its mechanical strength, making it suitable for high-temperature and pressure applications.
| Grade | En31 |
|---|---|
| Specification | 100Cr6, AISI SAE E52100, 100Cr6, 2258, 100C6 |
| Round bar size | Diameter: 3-~800mm |
| Hex Bar size | 2-100mm A/F |
| Flat bar size | Thickness: 2 -100mm |
| Width: 10 to 500mm | |
| Square bar size | 4 to 100mm |
| Angle bar size | 3mm*20mm*20mm~12mm*100mm*100mm |
| Section | 3.0 to 12.0mm thickness |
| Channel Bar | 80 x 40mm to 150 x 75mm section; 5.0 to 6.0mm thickness |
| Hollow Bar | 32mm OD x 16mm ID to 250mm OD x 200mm ID) |
| Billet Size | 1/2″ to 495mm Diameter |
| Rectangles Size | 33 x 30mm to 295 x 1066mm |
| Finish | Cold (bright) drawn, centreless ground,smooth turned, peeled, slit rolled edge, hot rolled, hot rolled annealed, Rough Turned, Bright, Polish, Grinding, Centreless Ground & Black |
| Tolerance | H8, H9, H10, H11, H12, H13K9, K10, K11, K12 or as per clients’ requirements |
| Surface | Bright, Hot Rolled Pickled, Cold Drawn, Sand Blasting Finished, Polished, Hairline |
| Condition | Hardened & tempered, annealed |
| Technique | en31 Hot Rolled, Cold Drawn, Cold Rolled, Forged Round Bar, Rod |
| Processing | Bar cutting to 650mm |
| Form | en31 Welding Rod, Round, Rod, T-Bar, Channel Bar, Precision Ground Bar, Flat Bar, Square, Blocks, Round Rod, Rings, Hollow, Triangle, Rectangle, Hex (A/F), Threaded, Half Round Bar, Profiles, Billet, Ingot, I/H Bar, Forging etc. |
| Our stockyad location for fast delivery across India | Surendranagar, Rajkot, Ranjangaon, Indore, Ahmedabad, Bhosari, Surat, Baroda, Chennai, Chakan, Hyderabad, Ahmednagar, Ajmer, Kolhapur, Thane, Belgaum, Kadi, Aurangabad, Pune, Hubli Mumbai, Nagpur, Jaipur, Nashik, Navi Mumbai |
| Carbon | 0.95 / 1.10 |
| Manganese | 0.40 / 0.70 |
| Silicon | 0.10 / 0.35 |
| Sulfur | Max 0.050 |
| Phosphorus | Max 0.040 |
| Chromium | 1.20 – 1.60 |
| Thermal Conductivity at °C | 20 | 350 | 700 |
| W/(m*K) | 44.5 | 45.0 | 46.0 |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
| Type | SIZES (mm) | SIZES (Inches) | ISO Tolerance |
|---|---|---|---|
| Cold Drawn and Polish | 3.00 – 75.00 | 1/8″ – 3.00″ | h8-h9-h10-h11 |
| Cold Drawn and Ground | 10.00 – 75.00 | 5/6″ – 2.50″ | h8-h9-h10-h11 |
| Peeled and Polished | 40.00 – 150.00 | 1.50″ – 6.00″ | h11, h11-DIN 1013 |
| Peeled and Ground | 20.00 – 50.00 | 3/4″ – 2.00″ | h9-h10-h11 |
| Cut to size on request (tolerance +2/-0 mm). Standard lengths of en31 Bars 2000 mm up to 6000 mm available | |||
| 5.0 | 45.0 |
| 6.0 | 50.0 |
| 7.0 | 55.0 |
| 8.0 | 60.0 |
| 9.0 | 65.0 |
| 10.0 | 70.0 |
| 12.0 | 75.0 |
| 16.0 | 80.0 |
| 20.0 | 90.0 |
| 25.0 | 100.0 |
| 30.0 | 130.0 |
| 35.0 | 160.0 |
| 40.0 | 200.0 |
The versatility of ST 35 and ST 35.8 tubing makes them popular across various industries due to their strength, thermal resistance, and ability to handle pressure. They are commonly found in applications such as boiler tubes, heat exchangers, superheaters, and pipeline systems in power plants and refineries. In the automotive industry, these tubes are used in hydraulic systems and engine components. In construction and machinery manufacturing, ST 35 tubing is preferred for structural and mechanical applications where reliability and durability are crucial. Its compatibility with welding and forming processes makes it perfect for custom fabrication, while its corrosion resistance under pressure ensures it’s suitable for transporting fluids and gases.
Filiz Steel is a leading manufacturer, supplier and exporter of high-quality Carbon Steel, Alloy Steel, Mild Steel and Galvanized Steel products. Our extensive product range includes Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets and Plates, catering to various industries in Istanbul, Turkey.
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