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 challenging 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 of material | X52 / L390 (N, M, Q, R) |
| X52 Steel LSAW / DSAW | 16’OD TO 54″ OD (8 MM TO 50 MM THK) |
| Standard | ISO 3183 L390/ API 5L X52 |
| API 5L X52 Seamless Pipe (OD) | 21.3 – 660mm ( Inch 1/2” – 26”) |
| X52 SAW | 16″ – 100″ NB |
| API 5L X52 PSL2 ERW and HFW | 1/2” NB – 24” NB |
| API 5L X52 PSL2 Pipe end | Square Cut, Chamfering, Grooved, Buttweld, Thread Cutting, Squared Ends, Deburring, Flanged Ends, Beveled End (BE), Socket, Cut Grooves, Vibrator Grinding, Coupling, Plain end (PE), Threaded Ends (Male & Female), Pub Joints, Screwed |
| Origin of X52 material | European, Chinese, Africa, Gulf, Asian, Turkey, Russian, American, Japan, Ukraine, Japanese, Indian, USA, Latin-American, Korean, |
| API 5L X52 Wall Thickness | SCH-STD, SCH160, SCH-XXS, SCH40, SCH-XS, SCH80 |
| Equivalent Standards | JIS, ANSI, EN, DIN, IS, UNI, ISO, AWWA, SS, AISI, NFA, BS, GOST, SA, KS, API, C ASTM, SAE, GB, |
| PSL Level | |
| Coating for API 5L X52 Line Pipe | Galvanized, 3PP, Varnished, 3LPE, lined pipe, Black Painting, 3PE, CRA clad, FBE, Anti-Rust Oil |
| Carbon Steel Grade | Mass fraction, % based on heat and product analyses | Carbon Equiv a | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| C | Si | Mn | P | S | V | Nb | Ti | Other | CE IIW | CE Pcm | |||||||||||
| max b | max | max b | max | max | max | max | max | max | max | ||||||||||||
| X52N | 0.24 | 0.45 | 1.4 | 0.025 | 0.015 | 0.1 | 0.05 | 0.04 | d,e,l | 0.43 | 0.25 | ||||||||||
| Pipe Grade | Tensile Properties – Pipe Body of SMLS and Welded Pipes PSL 2 | Seam of Welded Pipe | |||||
|---|---|---|---|---|---|---|---|
| Yield Strength a | Tensile Strength a | Ratio a,c | Elongation | Tensile Strength d | |||
| Rt0,5 PSI Min | Rm PSI Min | R10,5IRm | (in 2in) | Rm (psi) | |||
| Af % | |||||||
| Minimum | Maximum | Minimum | Maximum | Maximum | Minimum | Minimum | |
| X52 | 52,200 | 76,900 | 66,700 | 110,200 | 0.93 | f | 66,700 |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
| API 5L X52 Pipe types | API 5L X52 Pipe Size (mm) | Tolerances | |
|---|---|---|---|
| Hot rolled API 5L X52 Seamless Pipe | OD | <50 | ±0.50mm |
| ≥50 | ±1% | ||
| WT | <4 | ±12.5% | |
| ≥4～20 | +15%, -12.5% | ||
| >20 | ±12.5% | ||
| Cold drawn API 5L X52 Seamless Pipe | OD | 6～10 | ±0.20mm |
| 10～30 | ±0.40mm | ||
| 30～50 | ±0.45 | ||
| >50 | ±1% | ||
| WT | <1 | ±0.15mm | |
| >1～3 | + 15%, – 10% | ||
| >3 | + 12.5%, – 10% | ||
Filiz Steel is a leading supplier of high-quality Carbon Steel API X52 5L PSL 2 Pipes products in Istanbul, Turkey. We focus on steel solutions and offer a variety of products. This includes Carbon Steel, Alloy Steel, Mild Steel, and Galvanized Steel. Our products are Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets, and Plates. We are known for our good delivery and excellent customer care. We aim to provide strong and durable steel materials for many industrial uses. We work hard to meet high standards, making us a trusted partner for your steel needs.
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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