ARK Stainless Inc. is a trusted manufacturer and global supplier of high-performance Alloy Steel Round Bars, meticulously designed to deliver outstanding strength, toughness, and reliability in extreme industrial environments. These bars are engineered to perform exceptionally under high pressure, temperature fluctuations, and mechanical stress, making them a preferred choice for demanding engineering applications.
Our comprehensive range of alloy steel bars includes grades such as F1, F5, F9, F11, F12, F22, F91, and F92 Round Bars, each offering specific advantages depending on service conditions. These grades are alloyed with elements like chromium, molybdenum, vanadium, and niobium to improve hardness, creep resistance, and performance at elevated temperatures. They are ideal for use in thermal plants, chemical industries, refineries, power generation systems, and pressure vessels.
Manufactured in strict accordance with international specifications such as ASTM A182, A336, A479, and relevant ASME standards, our alloy steel bars are available in various diameters, lengths, finishes, and forms such as hot rolled, forged, normalized, or tempered. These bars are known for excellent machinability, weldability, and dimensional accuracy, and are fully customizable to suit specific design and performance requirements.
ARK Stainless Inc. conducts rigorous quality inspections including ultrasonic testing, mechanical testing, PMI, and third-party inspections to ensure the integrity and traceability of every batch. Complete documentation such as Mill Test Certificates (MTC), EN 10204 3.1/3.2 certifications, and heat treatment records are provided. Our Alloy Steel Round Bars are widely acknowledged for their superior durability, consistent performance, and long service life in critical applications.
| Grade | C | Mn | P | S | Si | Cr | Mo | V |
|---|---|---|---|---|---|---|---|---|
| F1 | 0.10–0.20 | 0.30–0.80 | ≤ 0.030 | ≤ 0.030 | 0.50 max | 0.50–0.80 | 0.44–0.65 | — |
| F5 | 0.15 max | 0.30–0.60 | ≤ 0.030 | ≤ 0.030 | 0.50 max | 4.00–6.00 | 0.44–0.65 | — |
| F9 | 0.15 max | 0.30–0.60 | ≤ 0.025 | ≤ 0.025 | 0.50 max | 8.00–10.00 | 0.90–1.10 | — |
| F11 | 0.05–0.15 | 0.30–0.60 | ≤ 0.025 | ≤ 0.025 | 0.50–1.00 | 1.00–1.50 | 0.44–0.65 | — |
| F12 | 0.05–0.15 | 0.30–0.61 | ≤ 0.025 | ≤ 0.025 | 0.50–1.00 | 0.80–1.25 | 0.44–0.65 | — |
| F22 | 0.05–0.15 | 0.30–0.60 | ≤ 0.025 | ≤ 0.025 | 0.50 max | 1.90–2.60 | 0.87–1.13 | — |
| F91 | 0.08–0.12 | 0.30–0.60 | ≤ 0.020 | ≤ 0.010 | 0.20–0.50 | 8.00–9.50 | 0.85–1.05 | 0.18–0.25 |
| F92 | 0.07–0.13 | 0.30–0.60 | ≤ 0.020 | ≤ 0.010 | 0.20–0.50 | 8.50–9.50 | 0.30–0.60 | 0.18–0.25 |
| Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) | Hardness (HBW) |
|---|---|---|---|---|
| F1 | 380–585 | 205 min | 22 | ≤ 197 |
| F5 | 415–585 | 205 min | 22 | ≤ 197 |
| F9 | 585–760 | 415 min | 20 | ≤ 241 |
| F11 | 415–585 | 205 min | 20 | ≤ 217 |
| F12 | 450–655 | 275 min | 20 | ≤ 217 |
| F22 | 620–795 | 415 min | 20 | ≤ 235 |
| F91 | 620–825 | 415 min | 20 | ≤ 250 |
| F92 | 620–860 | 450 min | 20 | ≤ 250 |
Alloy Steel F1 Round Bars are low-alloy steel bars formulated with chromium and molybdenum, designed to deliver superior performance under high-temperature and pressure conditions. These bars are commonly used in the fabrication of boilers, heat exchangers, pressure vessels, and piping systems in industries such as power generation, petrochemical, and oil & gas.
The combination of mechanical strength, good corrosion and oxidation resistance, and excellent weldability makes Alloy Steel F1 Round Bars suitable for both structural and high-stress environments. The material’s stability under thermal cycling and creep resistance also makes it highly reliable in long-term service at elevated temperatures.
All bars undergo rigorous quality checks such as ultrasonic testing, tensile and hardness testing, and chemical analysis to meet stringent international specifications and ensure safe, reliable performance.
| STANDARD | Werkstoff / DIN | UNS | EN |
|---|---|---|---|
| ASTM A182 Grade F1 | 1.5415 | K12822 | 15Mo3 |
Alloy Steel F5 Round Bars are high-performance chromium-molybdenum alloy bars designed for applications requiring elevated temperature strength and excellent resistance to oxidation and corrosion. These round bars are widely used in heat exchangers, pressure vessels, nuclear power systems, and refinery equipment, where high mechanical strength and thermal stability are essential.
The alloy composition of F5, with 5% chromium, enhances its ability to resist scaling and oxidation at high temperatures while maintaining strength and ductility. It also offers good weldability and machinability, making it a preferred material in demanding industrial environments.
All F5 Round Bars are manufactured under stringent quality controls and tested for dimensional accuracy, chemical composition, tensile properties, and ultrasonic integrity to meet international standards and ensure long-lasting performance.
| STANDARD | Werkstoff / DIN | UNS | EN |
|---|---|---|---|
| ASTM A182 Grade F5 | 1.7362 | K41545 | X11CrMo5 |
Alloy Steel F9 Round Bars are high-strength, low-alloy chromium-molybdenum steel bars primarily used in high-temperature service environments such as power generation, petrochemical, and refinery sectors. These bars offer outstanding mechanical strength, hardness, and resistance to oxidation, scaling, and corrosion under elevated temperatures and pressures.
With 9% chromium and 1% molybdenum, Alloy Steel F9 delivers enhanced creep resistance, superior thermal stability, and long service life, making it suitable for fabricating components like boiler tubes, headers, valves, and pressure vessels. Its chemical structure also supports excellent weldability and machinability.
Each F9 round bar undergoes thorough testing for dimensional accuracy, chemical integrity, mechanical strength, and ultrasonic flaw detection to ensure compliance with international quality standards and reliable performance in critical applications.
| STANDARD | Werkstoff / DIN | UNS | EN |
|---|---|---|---|
| ASTM A182 Grade F9 | 1.7386 | K90941 | 10CrMo9-10 |
Alloy Steel F11 Round Bars are chromium-molybdenum steel bars designed for high-temperature and high-pressure applications in industries such as power generation, petrochemical, refineries, and thermal processing. These bars exhibit excellent strength, toughness, and resistance to oxidation and scaling at elevated temperatures.
With a chemical composition that includes chromium and molybdenum, Alloy Steel F11 provides superior corrosion resistance and improved tensile strength. These properties make F11 round bars ideal for use in fabricating components like heat exchangers, boiler drums, superheaters, valves, and pressure vessels.
Every batch of Alloy Steel F11 round bars undergoes comprehensive quality checks including dimensional verification, ultrasonic inspection, mechanical and chemical testing to ensure compliance with ASTM/ASME standards and customer-specific requirements.
| STANDARD | Werkstoff / DIN | UNS | EN |
|---|---|---|---|
| ASTM A182 Grade F11 | 1.7335 | K11597 | 13CrMo4-5 |
Alloy Steel F12 Round Bars are chromium-molybdenum alloy steels known for their enhanced mechanical properties, excellent heat resistance, and corrosion resistance. These bars are primarily used in high-temperature and pressure environments such as steam boilers, heat exchangers, and power plants.
The presence of chromium and molybdenum enhances the strength and high-temperature oxidation resistance of Alloy Steel F12, making it ideal for service in extreme industrial applications. Its weldability and machinability also make it a preferred choice for fabricators working on heavy-duty engineering components.
All F12 round bars produced by ARK Stainless Inc. are subjected to stringent quality control procedures such as ultrasonic testing, chemical analysis, mechanical testing, and dimensional inspections to ensure conformity with international specifications and reliability in critical operations.
| STANDARD | Werkstoff / DIN | UNS | EN |
|---|---|---|---|
| ASTM A182 Grade F12 | 1.7338 | K11564 | 12CrMo19-5 |
Alloy Steel F22 Round Bars are high-performance alloy steels that exhibit exceptional strength, toughness, and resistance to high temperatures and pressures. These bars are composed primarily of chromium and molybdenum, providing excellent resistance to oxidation, corrosion, and creep, making them ideal for demanding environments such as pressure vessels, heat exchangers, and power plant components.
The F22 grade is widely used in the petrochemical and energy sectors due to its ability to maintain dimensional stability under severe thermal conditions. It also offers excellent machinability and weldability, ensuring efficient fabrication and extended service life.
ARK Stainless Inc. ensures every F22 round bar meets the highest standards through rigorous quality testing, including ultrasonic inspection, mechanical testing, chemical analysis, and dimensional checks. Our bars are certified and fully traceable to provide maximum assurance and performance.
| STANDARD | Werkstoff / DIN | UNS | EN |
|---|---|---|---|
| ASTM A182 Grade F22 | 1.7380 | K21590 | 10CrMo9-10 |
Alloy Steel F91 Round Bars are premium-grade alloy steels engineered for high-temperature, high-pressure service, especially in power generation, petrochemical, and thermal processing industries. These bars are known for their excellent creep strength, oxidation resistance, and mechanical stability at elevated temperatures, making them ideal for critical components such as superheaters, reheaters, and boiler tubes.
Composed of chromium, molybdenum, and vanadium, F91 bars provide superior hardness, corrosion resistance, and thermal fatigue strength. Their advanced metallurgy ensures long service life under stress-rupture conditions, meeting stringent performance standards in aggressive environments.
ARK Stainless Inc. supplies F91 round bars in a variety of dimensions, conditions, and finishes, with thorough quality testing and complete traceability. All bars are subject to mechanical testing, ultrasonic inspection, and chemical analysis to ensure compliance with ASTM and ASME specifications.
| STANDARD | Werkstoff / DIN | UNS | EN |
|---|---|---|---|
| ASTM A182 Grade F91 | 1.4903 | K91560 | X10CrMoVNb9-1 |
Alloy Steel F92 Round Bars are advanced high-performance alloy steels primarily used in ultra-supercritical power plants, petrochemical refineries, and high-temperature pressure vessels. Known for their outstanding creep rupture strength, high oxidation resistance, and excellent thermal stability, F92 bars are suitable for service at temperatures up to 620°C (1150°F).
These round bars are a part of the modified 9Cr-1Mo family and are composed of enhanced levels of chromium, molybdenum, tungsten, vanadium, and niobium, offering greater resistance to oxidation, steam corrosion, and stress-related deformation. Their microstructure stability ensures long operational life in high-pressure, high-temperature environments.
ARK Stainless Inc. delivers F92 round bars in various sizes, conditions, and finishes to meet the stringent demands of modern power and process industries. Each bar undergoes strict quality checks including ultrasonic testing, mechanical testing, and spectrochemical analysis for full compliance with international standards.
| STANDARD | Werkstoff / DIN | UNS | EN |
|---|---|---|---|
| ASTM A182 Grade F92 | 1.4901 | K92460 | X10CrWMoVNb9-2 |
