Yuhong Group Co.,Ltd
| WT | SCH 10S to SCH XXS |
| Application | Power Plant, Petrochemical, Boiler tube, Oil & Gas Industry |
| Standard | ASTM A335 / ASME SA335 |
| Delivery Time | 7days |
| End | Plain End, Beveled End |
| Payment Terms | L/C, T/T |
| Length | Single Random, Double Random & Cut Length |
| Packaging Details | Ply-wooden Case /Iron Case/ Bundle with plastic Cap |
| Type | Seamless |
| Product Name | Alloy Steel Seamless Pipe |
| High Light | ASTM A335 P91 Alloy Steel Seamless Pipe, Seamless Steel UNS K90901 Boiler Tube |
| Material | P91, UNS K90901, EN 1.4903 |
| O.D. | 1/2" TO 24 " or large |
| Model Number | ASTM A335 P91 Alloy Steel Seamless Pipe |
| Brand Name | YUHONG |
| Certification | ISO9001-2008, API 5L, API 5CT, PED, AD-2000, EN10204-3.1B |
| Place of Origin | China |
View Detail Information
Explore similar products
Alloy Steel Seamless Pipe ,ASTM A335/ ASME SA335 P9 , Fire Furance Pipe, Steam
Boiler ASME SA213 T11 Alloy Steel Seamless Tubes
Alloy Steel Tube, ASME SA213, ASTM A213, T1, T11, T12, T22, T23, T5, T9, T91,
ASTM A213 / SMES SA213 Alloy Steel Seamless Tubes For Boiler / Heat Exchanger
Product Specification
| WT | SCH 10S to SCH XXS | Application | Power Plant, Petrochemical, Boiler tube, Oil & Gas Industry |
| Standard | ASTM A335 / ASME SA335 | Delivery Time | 7days |
| End | Plain End, Beveled End | Payment Terms | L/C, T/T |
| Length | Single Random, Double Random & Cut Length | Packaging Details | Ply-wooden Case /Iron Case/ Bundle with plastic Cap |
| Type | Seamless | Product Name | Alloy Steel Seamless Pipe |
| High Light | ASTM A335 P91 Alloy Steel Seamless Pipe, Seamless Steel UNS K90901 Boiler Tube | Material | P91, UNS K90901, EN 1.4903 |
| O.D. | 1/2" TO 24 " or large | Model Number | ASTM A335 P91 Alloy Steel Seamless Pipe |
| Brand Name | YUHONG | Certification | ISO9001-2008, API 5L, API 5CT, PED, AD-2000, EN10204-3.1B |
| Place of Origin | China | ||
| High Light | ASTM A335 P91 boiler tube ，ASME SA335 alloy steel pipe ，EN 1.4903 seamless steel tube | ||
ASTM A335 / ASME SA335 P91 Alloy Steel Seamless Pipe for High-Temperature Service
ASTM A335 P91 (UNS K90901 / EN 1.4903) is a high-alloy martensitic steel with ~9% Chromium, Molybdenum, Vanadium, Niobium, and Nitrogen. Designed for boiler tubes and main steam piping, it offers exceptional creep strength up to 620°C and superior oxidation resistance—allowing thinner, lighter walls than traditional low-alloy grades. It is mandatory to use this material in the normalized + tempered condition. Critical warning: It is air-hardening; therefore, all welded joints require strict preheating (200–250°C) and mandatory Post-Weld Heat Treatment (730–760°C) to prevent cracking.
Key Features & Advantages (Why High-Alloyed Grade P91?)
Superior Oxidation Resistance: The ~9% Chromium content provides significantly better resistance to steam-side oxidation and high-temperature flue gas corrosion compared to low-alloy grades (e.g., T22/P22).
High Thermal Stability: Retains strength and structure integrity at extreme temperatures.
Low Thermal Expansion: Lower than austenitic stainless steels (e.g., 304/316), allowing for thinner wall thicknesses and better fatigue resistance under thermal cycling.
Reduced Wall Thickness: Excellent creep strength allows designers to use thinner pipe walls than P22/T22, reducing weight and thermal inertia.
Equivalent Material of ASTM A335 / ASME SA335 UNS K90901 P91 Boiler Tube EN 1.4903 Alloy Steel Seamless Pipe
| ASTM | ASME | Equivalent material |
|---|---|---|
| A335 P 91 | ASME SA 335 P91 | 1.4903, K90901, X10CrMoVNb9-1 |
Chemical Composition of ASME SA335 UNS K90901 P91 Boiler Tube EN 1.4903 Alloy Steel Seamless Pipe
| Element | Grade | P5 | P9 | P11 | P22 | P91 | P91 shall also include the following: |
|---|---|---|---|---|---|---|---|
| UNS | K41545 | S50400 | K11597 | K21590 | K91560 | ||
| Carbon | 0.15 max | 0.15 max | 0.05 – 0.15 | 0.05 – 0.15 | 0.08 – 0.12 | V at 0.18 – 0.25 | |
| Manganese | 0.30 – 0.60 | 0.30 – 0.60 | 0.30 – 0.60 | 0.30 – 0.60 | 0.30 – 0.60 | N at 0.030 – 0.070 | |
| Phosphorous, max | 0.025 | 0.025 | 0.025 | 0.025 | 0.020 | Ni at 0.40 max | |
| Sulfur, max | 0.025 | 0.025 | 0.025 | 0.025 | 0.010 | Al at 0.02 max | |
| Silicon | 0.50 max | 0.25 – 1.00 | 0.50 – 1.00 | 0.50 max | 0.20 -0.50 | Cb at 0.06 – 0.10 | |
| Chromium | 4.00 – 6.00 | 8.0 – 10.0 | 1.00 – 1.50 | 1.90 – 2.60 | 8.00 – 9.50 | Ti at 0.01 max | |
| Molybdenum | 0.45 -0.65 | 0.90 – 1.10 | 0.44 – 0.65 | 0.87 – 1.13 | 0.85 – 1.05 | Zr at 0.01 max | |
Mechanical Properties of ASME SA335 UNS K90901 P91 Boiler Tube EN 1.4903 Alloy Steel Seamless Pipe
| Grade | Tensile strength(MPa) | Yield strength(MPa) | Elongation(%) | Impact energy(J) | Hardness |
| P11 | ≥ 415 | ≥ 205 | ≥ 22 | ≥ 35 | ≤ 163HB |
| P12 | ≥ 415 | ≥ 220 | ≥ 22 | ≥ 35 | ≤ 163HB |
| P22 | ≥ 415 | ≥ 205 | ≥ 22 | ≥ 35 | ≤ 163HB |
| P5 | ≥ 415 | ≥ 205 | ≥ 22 | ≥ 35 | ≤ 187HB |
| P91 | 585~760 | ≥ 415 | ≥ 20 | ≥ 35 | ≤ 250HB |
| P92 | ≥ 620 | ≥ 440 | ≥ 20 | ≥ 35 | 250HB |
Application
A335/SA335 P91 is suitable for bending, flanging (vanstoning), and similar forming operations and for fusion welding. Its commonly used in below usages.
Superheaters & Reheaters (Boiler tubes).
Main Steam Piping and hot reheat piping.
Headers and manifolds in supercritical and ultra-supercritical coal-fired power plants.
Nuclear power heat exchangers.
Petrochemical high-temperature furnace tubes.
Company Details
Business Type:
Manufacturer,Distributor/Wholesaler,Importer,Exporter,Trading Company,Seller,Other
Year Established:
2007
Total Annual:
50M-70M
Employee Number:
50~850
Ecer Certification：
Verified Supplier
Yuhong Group is one of the large scale group company in China, more than 35 years experience in the international market, providing high-quality services to over 3000 customers, end user which like Aramco, Petrobras, Pemex, Petronas, Ecopetro, Petroecuador, …. till now Yuhong Grou... Yuhong Group is one of the large scale group company in China, more than 35 years experience in the international market, providing high-quality services to over 3000 customers, end user which like Aramco, Petrobras, Pemex, Petronas, Ecopetro, Petroecuador, …. till now Yuhong Grou...
Get in touch with us
Leave a Message, we will call you back quickly!