High Pressure Alloy Steel Seamless Tubes ASTM A335 Standard Boiler
Application
The high pressure pipe is always used in high pressure boilers
(which the operating pressure is over 9.8Mpa, the operating
temperature is between 450℃ and 650℃) as the heating surface pipe,
and economizer, superheater, reheater and petrochemical industry,
etc.
The A335 pipes are generally called chrome moly pipe as they have a
high level of Chromium and Molybdenum presence in it. While
Molybdenum increases the overall strength, resistance, elasticity,
hardenability and overall quality, moly ensures that the material
is more resistant to softening, restrains the growth of grains and
lessens the chances of embrittlement. It is the single additive
that is responsible for the increase in high temperature resistance
and it also improves the corrosion resistance to steel.
1. Standards
ASTM A106 ——Standard Specification for Seamless Carbon Steel Pipe
for High-Temperature Service
ASTM A335 ——Standard Specification for Seamless Ferritic
Alloy-Steel Pipe for High-Temperature Service
2. Application
For the high-pressure boiler and steam pipes, and the petrochemical
industry pipes;
Power plant; Chemical Fertilizer; Petrochemicals; Offshore Oils;
Gas Productions; Refineries and etc.
3. Steel pipes No. of main production:
ASTM A335 Grade P5, P9, P11, P12, P22, P91, P92
ASTM A106 Grade B, C
4. Dimensional Tolerance
| Pipe types | OD (mm) | Tolerance | WT (mm) | Tolerance |
| High Pressure Boiler Tube | 219~457 | ±1.0％ | ≤20 | -10% ~ +12.5% |
| 20~40 | -10% +10% |
| 457~1422 | ±0.9％ | ＞40~70 | -7％, +9％ |
| ＞70~20 | -6％, +8％ |
5. Chemical Composition:
| High Pressure Boiler Tube Chemical Requirements |
| Standard | Grade | UNS Designation | Composition, % |
| C | Mn | P | S | Si | Cr | Mo | Ni | V | Others |
| ASTM A335 | P5 | K41545 | 0.15max | 0.30-0.60 | 0.025 | 0.025 | 0.50max | 4.00-6.00 | 0.45-0.65 | | | ... |
| P9 | S50400 | 0.15max | 0.30-0.60 | 0.025 | 0.025 | 0.25-1.00 | 8.00-10.00 | 0.90-1.10 | | | ... |
| P11 | K11597 | 0.05-0.15 | 0.30-0.60 | 0.025 | 0.025 | 0.50-1.00 | 1.00-1.50 | 0.44-0.65 | | | ... |
| P12 | K11562 | 0.05-0.15 | 0.30-0.61 | 0.025 | 0.025 | 0.50 max | 0.80-1.25 | 0.44-0.65 | | | ... |
| P22 | K21590 | 0.05-0.15 | 0.30-0.60 | 0.025 | 0.025 | 0.50 max | 1.90-2.60 | 0.87-1.13 | | | ... |
| P91 | K91560 | 0.08-0.12 | 0.30-0.60 | 0.02 | 0.01 | 0.20-0.50 | 8.00-9.50 | 0.85-1.05 | 0.4 | 0.18-0.25 | N 0.030-0.070 |
| Al 0.02max |
| Cb 0.06-0.10 |
| Ti 0.01 max |
| Zr 0.01max |
| P92 | K92460 | 0.07-0.13 | 0.30-0.60 | 0.02 | 0.01 | 0.50 max | 8.50-9.50 | 0.30-0.60 | 0.4 | 0.15-0.25 | N 0.03-0.07 |
| Al 0.02 max |
| Cb 0.04-0.09 |
| W 1.5-2.00 |
| B 0.001-0.006 |
| Ti 0.01 max |
| Zr 0.01 max |
| ASTM A106 | Grade B | | 0.3 | 0.29–1.06 | 0.035 | 0.035 | 0.1 | 0.4 | 0.15 | 0.4 | 0.08 | |
| Grade C | | 0.35 | 0.29–1.06 | 0.035 | 0.035 | 0.1 | 0.4 | 0.15 | 0.4 | 0.08 | |
6. Mechanical Properties
| Standards | Steel pipes No. | Tensile strength | Yield strength | Elongation | Impact energy | Hardness |
| (Mpa) | (Mpa) | (%) | (J) |
| ASTM A335 | P5 | ≥415 | ≥205 | ≥22 | ≥35 | ≤187HB |
| P9 | ≥415 | ≥205 | ≥22 | ≥35 | |
| P11 | ≥415 | ≥205 | ≥22 | ≥35 | ≤163HB |
| P12 | ≥415 | ≥220 | ≥22 | ≥35 | ≤163HB |
| P22 | ≥415 | ≥205 | ≥22 | ≥35 | ≤163HB |
| P91 | 585～760 | ≥415 | ≥20 | ≥35 | ≤250HB |
| P92 | ≥620 | ≥440 | ≥20 | ≥35 | ≤250HB |
| ASTM A106 | Grade B | ≥415 | ≥240 | ≥22 | ≥35 | / |
| Grade C | ≥485 | ≥275 | ≥20 | ≥35 | / |
7. Available Size Range:
| OD | Thickness |
| mm | inch | mm | SCH |
| 88.9~1422 | 3''~ 56'' | 2.11~140 | ≥SCH10 |
| *If the steel grades and size you are looking for are not listed
above, please contact us for further information. |
