ASTM A335 P91 Alloy Steel Seamless Pipes Manufacturer Supplier & Exporter
Amardeep Steel Centre is a premier Manufacturer, Supplier, and Exporter of high-performance ASTM A335 P91 Pipes. Recognized as a leading Creep Strength Enhanced Ferritic (CSEF) steel, our A335 P91 Alloy Steel Pipe products are engineered for exceptional reliability in the most demanding high-temperature, high-pressure environments, particularly in advanced power generation and process industries. Trust Amardeep Steel Centre for Seamless alloy steel pipe P91 that meets rigorous international standards and delivers unparalleled performance.
What are ASTM A335 P91 Alloy Steel Seamless Pipes?
ASTM A335 P91 Alloy Steel Seamless Pipes, commonly designated by their UNS number K91560 Pipe, represent a highly sophisticated grade of P91 Ferritic alloy steel. This material, often sought after as Alloy Steel P91 Pipes, is engineered as a modified 9% Chromium, 1% Molybdenum steel, further enhanced by precisely controlled additions of Vanadium, Niobium, and Nitrogen. The specific P91 material composition and subsequent heat treatment are paramount to achieving its renowned high-temperature performance. Often referred to as Chrome moly P91 pipe, Grade P91 develops a fine, tempered martensitic microstructure through a carefully executed normalizing and tempering process. This specialized microstructure, directly resulting from its unique P91 chemical composition, provides exceptional high-temperature strength, superior long-term creep resistance, and enhanced fatigue life when compared to conventional chromium-molybdenum steels. The seamless construction of these pipes ensures maximum structural integrity, which is critical for their intended service in demanding conditions.
The ASTM A335 Grade P91 standard, and its ASME equivalent ASME SA335 P91 Pipe, outlines the requirements for these High-temperature steel pipe products, which are primarily used in power generation and petrochemical industries. A key distinction within this grade is the existence of two types:
ASTM A335 P91 Type 1
ASTM A335 P91 Type 1 was the original formulation of this advanced 9Cr-1Mo-VNb steel. It laid the groundwork for the exceptional creep strength and high-temperature performance associated with the P91 grade. While still covered under the UNS K91560 designation, Type 1 established the foundational chemistry and property targets. However, advancements in steelmaking practices and a deeper understanding of the micro-alloying effects led to further refinements.
ASTM A335 P91 Type 2
ASTM A335 P91 Type 2 is the more contemporary and predominantly specified version of this grade in modern applications. It builds upon the foundation of Type 1 with often more stringent controls over the p91 material composition (particularly the balance of micro-alloying elements like Vanadium, Niobium, and Nitrogen, as well as certain residual elements) and potentially more refined processing and heat treatment parameters. These optimizations in P91 Type 2 are aimed at achieving even more consistent and superior creep rupture strength and toughness, making it the preferred choice for new constructions in ultra-supercritical (USC) power plants and other critical high-temperature, high-pressure services. Unless a specific project dictates Type 1, references to "P91" or Alloy Steel P91 Pipes in new applications typically imply P91 Type 2.
The primary advantage of ASTM A335 P91 Alloy Steel Seamless Pipes, particularly Type 2, lies in their capacity to operate reliably and efficiently at significantly higher temperatures and pressures. This capability is indispensable for enhancing the thermal efficiency, reducing emissions, and ensuring the operational integrity of advanced thermal power plants, especially in components like main steam lines and critical sections of USC boilers.
Key Properties & Advantages of ASTM A335 Grade P91 Pipes
Choosing Amardeep Steel Centre's ASTM A335 P91 Pipes (typically Type 2 for optimal performance) provides critical benefits for high-stakes applications:
- Exceptional Creep Strength: Maintains mechanical integrity under long-term stress at very high temperatures (up to approx. 600-620°C / 1112-1150°F).
- Superior High-Temperature Strength: Offers significantly higher allowable stresses at elevated temperatures compared to lower alloy steels like P22.
- Good Oxidation Resistance: The high chromium content provides good resistance to scaling and oxidation in high-temperature steam and flue gas environments.
- Lower Thermal Expansion Coefficient: Compared to austenitic stainless steels, leading to reduced thermal stresses in cyclic operations.
- Higher Thermal Conductivity: Compared to austenitic stainless steels, allowing for better heat transfer.
- Thinner Wall Designs: The high strength of A335 P91 Alloy Steel Pipe allows for thinner pipe walls for a given design pressure, reducing weight and material costs.
- Improved Resistance to Thermal Fatigue: Due to the combination of strength and thermal properties.
- Weldability: While requiring specialized procedures, P91 is weldable, allowing for complex piping systems. Supplier expertise in handling and fabrication is key.
ASTM A335 P91 Pipe Specifications
Amardeep Steel Centre, a leading Supplier and Manufacturer in the P91 market, provides ASTM A335 P91 Pipes (primarily Type 2, the industry standard for new constructions) manufactured to precise international standards. Understanding the p91 material composition is critical to appreciating its high-temperature capabilities.
| Specification Attribute | Details for ASTM A335 P91 Pipes |
|---|---|
| Primary Standard | ASTM A335 / ASME SA335 |
| Grade | P91 (Type 1 and Type 2, with Type 2 being predominantly used) |
| UNS Designation | UNS K91560 Pipe (Covers both Type 1 and Type 2) |
| Material Type | P91 Ferritic Alloy Steel (Creep Strength Enhanced Ferritic - CSEF) |
| Manufacturing Process | Seamless (Hot Finished or Cold Drawn). Seamless alloy steel pipe P91 construction is mandatory for this grade under A335. |
| Outer Diameter (OD) | NPS 1/2” to NPS 24” (21.3mm to 610mm). Larger diameters may be available as custom orders. |
| Wall Thickness (WT) | Schedule 20 through Schedule XXS, and heavier walls as required by design pressure. Common schedules include SCH 40, 80, 120, 160. |
| Length | Single Random Length (SRL), Double Random Length (DRL), and Custom Cut Lengths up to specified maximums (e.g., 12-14 meters). |
| End Connections | Plain End (PE), Bevelled End (BE) as per ASME B16.25 for welding. |
| Testing & Certification | Includes hydrostatic testing, non-destructive examination (NDE), tensile tests, hardness tests. Mill Test Certificate (MTC) to EN 10204 3.1 or 3.2 provided, detailing the p91 chemical composition and confirming grade type if specified. |
P91 Chemical Composition (Typical wt % as per ASTM A335 for Type 1 & Type 2)
The exceptional performance of ASTM A335 P91 Pipes is directly attributed to its meticulously controlled p91 chemical composition. This specialized p91 material composition is designed to deliver superior creep strength and stability at high temperatures.
| Alloy Steel P91 | C (Carbon) | Cr (Chromium) | Mn (Manganese) | Mo (Molybdenum) | P (Phosphorus) | S (Sulfur) | Si (Silicon) | V (Vanadium) | Nb (Niobium) | N (Nitrogen) | Al (Aluminum) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Content (wt %) | 0.08 - 0.12 | 8.00 - 9.50 | 0.30 - 0.60 | 0.85 - 1.05 | 0.020 max | 0.010 max | 0.20 - 0.50 | 0.18 - 0.25 | 0.06 - 0.10 | 0.030 - 0.070 | 0.02 max* |
Mechanical Properties of ASTM A335 P91 Pipes
| Property | Value |
|---|---|
| Tensile Strength | 85,000 psi (585 MPa) minimum |
| Yield Strength (0.2% offset) | 60,000 psi (415 MPa) minimum |
| Elongation in 2 inches (50 mm) | 20% minimum |
| Hardness | 250 HBW / 25 HRC (maximum) |
ASTM A335 P91 Pipe Equivalent Materials
| Standard/Designation | Details |
|---|---|
| ASME | SA335 P91 |
| Common Material Designations | T91 (tube equivalent), X10CrMoVNb9-1 |
| EN (European Norm) | EN 10216-2 (often grade X10CrMoVNb9-1 or 1.4903) |
| DIN (German) | Approximately 1.4903 (X10CrMoVNb9-1) |
| Other Equivalent Standards (for similar chemistry/application) | ASTM A213 T91 (for seamless tubes), GOST 550-75, NBR 5603 |
Comparison with Other ASTM A335 Grades
| ASTM A335 Grades | BSi Equivalent Ref. | Material Focus |
|---|---|---|
| Gr. P5 | 3604/625 | 5% Cr 1/2% Mo |
| Gr. P9 | 3604/629 | 9% Cr 1% Mo |
| Gr. P11 | 3604/621 | 1 1/4% Cr 1/2% Mo |
| Gr. P12 | 3604/620 | 1% Cr 1/2% Mo |
| Gr. P22 | 3604/622 | 2 1/4% Cr 1% Mo |
| Gr. P91 | N/A (Modern CSEF) | ~9% Cr 1% Mo + V, Nb, N (Modified) |
ASTM A335 P91 Pipe Size Chart
The outside diameter and tolerances for ASTM A335 P91 Seamless Pipes are governed by standards such as ASTM A335 itself and the general requirements specified in ASTM A530/A530M. Below are typical OD tolerances based on Nominal Pipe Size (NPS):
| O.D.(mm) x Thk(mm) | O.D.(mm) x Thk(mm) | O.D.(mm) x Thk(mm) |
|---|---|---|
| 38.1 x 3.2 | 57.0 x 4.9 | 76.2 x 4.0 |
| 38.1 x 4.0 | 57.0 x 6.3 | 76.2 x 5.0 |
| 38.1 x 6.3 | 57.0 x 7.9 | 76.2 x 6.3 |
| 42.4 x 3.2 | 60.3 x 3.2 | 82.5 x 4.5 |
| 42.4 x 4.0 | 60.3 x 3.6 | 88.9 x 3.2 |
| 44.5 x 3.2 | 60.3 x 5.0 | 88.9 x 3.6 |
| 44.5 x 6.3 | 63.5 x 3.2 | 88.9 x 4.0 |
| 48.3 x 3.2 | 63.5 x 3.6 | 101.6 x 3.6 |
| 48.3 x 3.6 | 63.5 x 4.0 | 101.6 x 4.5 |
| 50.8 x 4.5 | 63.5 x 6.3 | 101.6 x 6.3 |
| 51.0 x 3.2 | 63.5 x 7.9 | 114.3 x 3.6 |
| 51.0 x 3.6 | 70.0 x 3.2 | 114.3 x 5.0 |
| 51.0 x 6.3 | 70.0 x 3.6 | 139.7 x 4.0 |
| 57.0 x 3.2 | 70.0 x 6.3 | 139.7 x 5.0 |
| 57.0 x 3.6 | 76.2 x 3.6 | 139.7 x 6.3 |
Manufacturing & Heat Treatment of ASTM A335 P91 Pipes
The superior performance of P91 boiler pipe and steam piping, particularly P91 Type 2, hinges on meticulous manufacturing and, critically, precise heat treatment to develop the properties dictated by its p91 chemical composition.
Manufacturing Process for ASTM A335 P91 Pipes:
- Premium Raw Material: Starting with high-quality alloy steel billets with tightly controlled chemistry conforming to ASTM A335 Grade P91.
- Seamless Manufacturing: Employing hot piercing and rolling, or hot extrusion, followed by optional cold drawing for tighter tolerances and improved surface finish of the Seamless alloy steel pipe P91.
Heat Treatment Process for ASTM A335 Grade P91:
- Normalizing: Pipes are uniformly heated to a temperature not less than 1040°C [1900°F], held for sufficient time based on thickness to achieve complete austenitization and dissolution of carbides/nitrides, and then cooled in air or by accelerated cooling (e.g., forced air).
- Tempering: After normalizing and cooling, pipes are reheated to a temperature not less than 730°C [1350°F], held for an appropriate time (again, thickness dependent), and then cooled. This tempering step precipitates fine, stable carbides and nitrides (MX type, M23C6) which are key to the high-temperature strength and creep resistance derived from the p91 material composition.
Amardeep Steel Centre employs advanced, calibrated heat treatment furnaces and strict process controls to ensure every P91 pipe (primarily Type 2) achieves the desired microstructure and mechanical properties.
Alloy Steel P91 Seamless Pipe Wall Thickness:
| NPS [DN] Designator | Tolerance, % from Specified | |
|---|---|---|
| Over | Under | |
| 1/8 to 2 1/2 [6 to 65] incl., all t/D ratios | 20.0% | 12.5% |
| Above 2 1/2 [65], t/D < or = 5% | 22.5% | 12.5% |
| Above 2 1/2 [65], t/D > 5% | 15.0% | 12.5% |
| (t = Specified Wall Thickness; D = Specified Outside Diameter) | ||
Applications of ASTM A335 P91 Pipes
The exceptional high-temperature capabilities of ASTM A335 P91 Pipes, derived from its specialized p91 material composition (especially Type 2), make them the material of choice for the most demanding sections of modern thermal power plants and other high-temperature process industries:
- Main Steam Piping: Carrying superheated steam from the boiler to the turbine in ultra-supercritical (USC) and advanced ultra-supercritical (A-USC) coal-fired power plants.
- Hot Reheat Piping: Transporting reheated steam back to the turbine.
- Headers & Manifolds: Distributing high-pressure, high-temperature steam.
- P91 Boiler Pipe: For critical boiler components like superheater and reheater outlet sections.
- Heat Recovery Steam Generators (HRSGs): In high-efficiency combined cycle power plants.
- Petrochemical & Refining: High-temperature process piping where conditions exceed the capabilities of lower alloy steels like P22.
- Other High-Temperature Industrial Processes: Applications requiring robust High-temperature steel pipe with excellent creep resistance.
The use of ASTM A335 P91 Alloy Steel Seamless Pipes enables power plants to operate at higher temperatures and pressures, leading to increased thermal efficiency and reduced emissions.
Why Choose Amardeep Steel Centre for Your ASTM A335 P91 Pipes?
Amardeep Steel Centre is your trusted Manufacturer and Supplier of ASTM A335 P91 Pipes in India and for global export, offering distinct advantages:
- Specialized Expertise in P91: Deep understanding of the metallurgy, manufacturing intricacies, critical heat treatment, and application requirements of ASTM A335 Grade P91, including its vital p91 chemical composition. We primarily supply P91 Type 2 for its enhanced properties.
- Precision Seamless Manufacturing: Advanced facilities to produce Seamless alloy steel pipe P91 with consistent quality, dimensional accuracy, and superior metallurgical properties.
- Stringent Heat Treatment Control: Our heat treatment processes are meticulously controlled to ensure the development of the optimal tempered martensitic microstructure essential for P91 performance based on its p91 material composition.
- Global Exporter with Proven Reliability: As experienced P91 pipe exporters from India, we ensure timely and secure delivery worldwide, adhering to international standards for packaging and documentation.
- Competitive Price & Lifecycle Value: We offer an optimal Price for premium quality Chrome moly P91 pipe, considering its long-term performance and contribution to plant efficiency.
- Uncompromising Quality Assurance: Our ISO 9001 certified processes, comprehensive testing (including NDE), and detailed MTCs guarantee that every A335 P91 Alloy Steel Pipe meets or exceeds specifications.
- Dedicated Technical & Fabrication Support: Our experts provide guidance on material selection, welding procedures (critical for P91), and fabrication best practices for P91 Ferritic alloy steel.
Related Products to ASTM A335 P91 Pipes
Amardeep Steel offers a comprehensive range of alloy steel pipes and tubes for diverse high-temperature and high-pressure applications. Alongside our premium ASTM A335 P91 Pipes, explore these other common ASTM A335 grades and related products:
Other ASTM A335 Chrome-Molybdenum Alloy Steel Seamless Pipes:
- ASTM A335 P1 Alloy Seamless Pipes
- ASTM A335 P2 Alloy Seamless Pipes
- ASTM A335 P5/P5b/P5c Seamless Pipes
- ASTM A335 P9 Alloy Seamless Pipes
- ASTM A335 P11 Alloy Seamless Pipes
- ASTM A335 P12 Alloy Seamless Pipes
- ASTM A335 P22 Alloy Seamless Pipes
- ASTM A335 P23 Alloy Seamless Pipes
- ASTM A335 P92 Alloy Seamless Pipes
Equivalent Tube Grades:
Explore our full range of Alloy Steel Pipes & Tubes for comprehensive solutions.
Get Your ASTM A335 P91 Pipes Price & Consultation
For the latest Price, detailed technical specifications, or to discuss your critical project requirements for ASTM A335 P91 Pipes (Type 1 or the more common Type 2), contact the high-performance alloy experts at Amardeep Steel Centre today. We are committed to providing the highest quality ASTM A335 P91 Alloy Steel Seamless Pipes, with a clear understanding of its critical p91 chemical composition and p91 material composition, tailored to your most demanding applications.
ASTM A335 P91 Pipe Price in India
Please note that the following prices are indicative and subject to change based on market fluctuations, quantity, specific dimensions, make, and other factors. For the most current Price and a customized quotation for your ASTM A335 P91 Pipes requirements, we strongly encourage you to contact us directly.
| Size | MSL Make (₹) | ISMT Make (₹) | JSL Make (₹) |
|---|---|---|---|
| 1/2" | 4,264.71 | 4,257.35 | 4,272.06 |
| 3/4" | 4,044.12 | 4,036.76 | 4,051.47 |
| 1" | 3,897.06 | 3,889.71 | 3,904.41 |
| 1.25" | 3,852.94 | 3,845.59 | 3,860.29 |
| 1.5" | 3,750.00 | 3,742.65 | 3,757.35 |
FAQ’s About ASTM A335 P91 Alloy Steel Seamless Pipes
1. What is ASTM A335 P91 material?
A335/SA335 P91 is a ferritic alloy steel that has extremely high strength and does not degrade over time, allowing it to have creep resistant properties. It is also known by the name 9 Cr 1 Mo steel, or chrome moly pipe, based on its chemical composition.
2. What is the difference between A335 P91 Type 1 and Type 2?
ASTM A335 P91 Type 1 & Type 2 primarily differ in Mn, S, Si, N, Sn and Sb content and Type 2 has stricter controls on element content than Type 1. When discussing P91 type 1 and type 2 they both must achieve a hardness of 190 - 250 [HBW] or 196 - 265 [HV] or 91 HRBW to 25 HRC.
3. What is the hardness of A335 P91?
P91 maximum hardness shall not exceed [250 HB/265 HV or 25HRC]. Bend Test Notes: The bend test shall be used instead of the flattening test for pipe whose nominal diameter exceeds NPS 25 and whose diameter to wall thickness ratio is less than or equal to 7.0.
4. What is the temperature range for A335 P91?
ASTM A335 P91 shall be heat treated with normalize and temper, or quench and tempering, normalize temperature [1040-1080℃] 1900 - 1975℉ range, subcritical anneal or temper minimum, or temperature ranging from [730-800℃] 1350-1470℉.