Products Description
Product Specifications
| Standards | ASTM A335/A335M |
| Steel Grades | P1 Grade P2 Grade P5 Grade P5b Grade P5c Grade P9 Grade P11 Grade P12 Grade P15 Grade P21 Grade P22 Grade P23, etc. |
| Equivalent Standards | EN 10216-2, JIS G3462, GB/T 5310,etc. |
| Outer Diameter (OD) | 10.3 mm – 610 mm |
| Wall Thickness (WT) |
2.0 mm – 120 mm |
| Length | 6/12 m, or customized |
| Surface Treatment |
Black, shot-blasted or pickled, as agreed |
| Production Process | Hot-rolled / cold-rolled / cold-drawn |
| Condition | Heat treatment |
TORICH Chrome Moly alloy pipe is manufactured through a seamless process-hot-rolled piercing followed by cold rolling or cold drawing-ensuring no longitudinal welds. These pipes are ideally suited for high-pressure applications, such as main steam and reheat steam piping. Through a comprehensive normalizing and tempering heat treatment, the material achieves a uniform microstructure with controlled grain size, enabling it to withstand the repeated thermal shocks and cyclic stresses associated with frequent start-stop operations-a critical requirement for power plant units engaged in peak-load regulation.
A335 Chrome-Moly pipes offer stable performance in the 425–625°C range, with long-term creep-rupture strength significantly higher than A106 Gr.B carbon steel or standard low-alloy steel pipes (carbon steel is generally recommended only for service temperatures below 425°C). Furthermore, the high strength of the P91 grade allows for reduced wall thickness, which lowers both the overall weight of the piping system and the associated support costs.
Customized Services
- Material Grade Selection: TORICH offers a wide range of material grades, including P1, P2, P5, P5b, P5c, P9, P11, P12, P15, P21, P22, P23, and others.
- Heat Treatment Customization: For P91/P92 grades, which have narrow temperature windows for normalizing and tempering, the tempering temperature can be adjusted according to project specifications (typically 730–780 °C for P91, and up to 750–780 °C for P92), with precise documentation of the holding time.
- Coatings and Anti-Corrosion: Options include 3PE (polyethylene) or FBE (fusion-bonded epoxy) external anti-corrosion coatings, as well as aluminizing (or aluminum-zinc coating) for both internal and external surfaces-ideal for overhead piping in power plants located in marine or highly corrosive environments.
Chemical Composition
| Grade |
C |
Mn |
Si |
Cr |
Mo |
Ni |
V |
Nb |
N |
W |
P (max.) |
S (max.) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
P11 |
0.05–0.15 |
0.3–0.6 |
0.5–1.0 |
1.0–1.5 |
0.44–0.65 |
- |
- |
- |
- |
- |
0.025 |
0.025 |
|
P22 |
0.05–0.15 |
0.3–0.6 |
≤0.5 |
1.9–2.6 |
0.87–1.13 |
- |
- |
- |
- |
- |
0.025 |
0.025 |
|
P91 |
0.08–0.12 |
0.3–0.6 |
0.2–0.5 |
8.0–9.5 |
0.85–1.05 |
≤0.40 |
0.18–0.25 |
0.06–0.10 |
0.03–0.07 |
- |
0.020 |
0.010 |
|
P92 |
0.07–0.13 |
0.3–0.6 |
≤0.5 |
8.5–9.5 |
0.30–0.60 |
≤0.40 |
0.15–0.25 |
0.04–0.09 |
0.03–0.07 |
1.5–2 |
0.020 |
0.010 |
Mechanical Properties
| Property |
Tensile Strength (MPa), min. |
Yield Strength (MPa), min. |
Elongation |
Heat Treatment |
|---|---|---|---|---|
|
P11 |
415 |
205 |
As specified by standard |
Grade-specific heat treatment |
|
P22 |
415 |
205 |
As specified by standard |
Grade-specific heat treatment |
|
P91 |
585 |
415 |
As specified by standard |
Normalizing and tempering |
|
P92 |
620 |
440 |
As specified by standard |
Normalizing and tempering |
Possible Alternative Grades
- P12 has a slightly lower chromium content than P11; it offers comparable creep strength under medium-temperature steam conditions (425–500°C), superior weldability, and a slightly lower cost, making it suitable for medium-pressure feedwater and secondary steam piping.
- P21 (2.25Cr-1Mo-V) incorporates vanadium to enhance creep strength, providing better long-term performance than P22 at temperatures between 540°C and 570°C. Its drawbacks include more stringent welding requirements and higher raw material costs; it is primarily used in high-pressure, hydrogen-service equipment.
- P91H is an improved version of P91 designed for demanding applications such as superheaters and headers in supercritical boilers. It serves as an upgraded replacement for P91, sharing the same upper temperature limit while carrying a slightly higher material cost than standard P91.
- P122 is a heat-resistant steel with a higher chromium content. It exhibits better creep performance than P92 at temperatures above 620°C, making it suitable for advanced ultra-supercritical (A-USC) power units operating at higher parameters (620–650°C).
application areas
- P11: Superheater and reheater piping for subcritical boilers (up to approx. 538 °C), steam headers and distribution manifolds, and transfer lines for refinery process heaters.
- P22: Main steam piping and high-temperature reheat steam piping for supercritical boilers; piping for hydrotreating/hydrocracking reactor loops (in hydrogen environments at temperatures above 260 °C); and high-pressure steam headers in power plants.
- P91: Outlet headers for high-temperature superheaters, main steam piping, and reheat steam piping in power plant boilers; suitable for high-temperature, high-pressure steam service at temperatures up to approx. 593 °C.
- P92: Final-stage superheater headers, final-stage reheater headers, main steam piping, and hot-reheat steam piping for ultra-supercritical units; designed for temperatures reaching the 620 °C range.
Products Show
Testing Equipment
Factory Equipment
Pickling equipment
Polishing equipment
Cold drawing equipment
Products Package
FAQ
Q: How should one choose between P11, P22, P91, and P92?
A: Selection is based on design temperature: use P11 for 425°C–510°C; P22 for 510°C–565°C or in hydrogen-rich environments; P91 for 565°C–600°C where a reduction in wall thickness is required; and P92 for ultra-supercritical power generation units operating at 600°C–625°C.
Q: Do these pipes require preheating before welding and post-weld heat treatment (PWHT)?
A: Yes, all four grades require both. For P11/P22, typical preheating is 150–250°C, with a PWHT range of 675–730°C. For P91/P92, preheating is generally 200–300°C; the PWHT temperature window is narrower (approximately 730–770°C for P91), and there are stricter requirements regarding heating/cooling rates and holding times.
Q: Can the products be supplied with EN 10204 3.1 or 3.2 certificates?
A: Yes. For power generation projects, an EN 10204 3.1 certificate is typically provided with the shipment, covering the heat/batch number, chemical composition, mechanical properties, heat treatment records, and non-destructive testing (NDT) results.
Hot Tags: chrome moly alloy pipe, China, suppliers, manufacturers, factory, customized, wholesale, price, OEM, mill, producer, for sale, dealer carbon steel tube
