Alloy Seamless Steel Pipe

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Alloy Seamless Steel Pipe

ASTM A335 P11 P22 P91 alloy steel pipe for high temperature steam service
Alloy Seamless Steel Pipe
High pressure alloy steel seamless tubing with normalized and tempered finish
High pressure alloy steel seamless tubing with normalized and tempered finish
Heavy wall alloy steel pipe ASME SA335 for power plant piping systems

Product Name: Alloy Seamless Steel Pipe, ASTM A335 Alloy Pipe
Size Range: OD 1/8" - 26"
Wall Thickness: SCH 30, SCH 40, SCH 60, SCH 80, SCH 120, SCH 140, SCH 160, SCH XS, SCH XXS, SCH STD
Length: Single random, double random, cut length up to 23 m
Standards and Grades: ASTM A335 P5, P9, P11, P22, P91; ASTM A333; DIN 17175; JIS G3458
Ends: Plain end, beveled end, threaded end
Applications: Boiler, power plant, high temperature, high pressure and industrial piping systems
Delivery: Within 30 days, depending on order quantity
Packing: Bundled, in bulk




  • Overview
  • Specification
  • Standard
  • Process
  • Packing

High-Performance Alloy Seamless Steel Pipe–Heat & Corrosion Resistant Solutions

Our Alloy Seamless Steel Pipes are engineered for high-temperature, high-pressure, and corrosive environments where standard carbon steel fails. By incorporating elements like Chromium, Molybdenum, and Nickel, these pipes offer superior mechanical properties, creep resistance, and durability. Whether for power generation or refinery processes, our alloy piping ensures long-term operational safety.


Common Standards and Steel Grades

We provide a wide range of low-alloy and high-alloy seamless pipes following international benchmarks:

ASTM A335 (ASME SA335): The "Chrome-Moly" pipe standard for high-temperature service.

Common Grades: P5, P9, P11, P22, P91, P92.

ASTM A213 (ASME SA213): Seamless ferritic and austenitic alloy-steel boiler, superheater, and heat-exchanger tubes.

Common Grades: T5, T9, T11, T22, T91.

DIN 17175: Heat-resistant seamless steel tubes.

Common Grades: 13CrMo44, 10CrMo910.

EN 10216-2: Seamless steel tubes for pressure purposes.

Common Grades: 16Mo3, 13CrMo4-5.


Dimensions and Technical Specifications

We offer customized sizing and heavy-wall options to meet specific engineering drawings:

Feature

Specification Range

Outer Diameter (OD)

1/4” to 36” (13.7mm – 914.4mm)

Wall Thickness (WT)

SCH 40, SCH 80, SCH 160, SCH XXS (up to 100mm for heavy wall)

Length

Single Random, Double Random, or Fixed Length (up to 12m or 15m)

Surface Treatment

Bare, Black Painting, Anti-corrosion Oil, or Galvanized

End Preparation

Beveled Ends (BW), Plain Ends (PE), or Threaded & Coupled


Core Application Fields

Alloy seamless pipes are the backbone of critical infrastructure and heavy industry:

Power Generation: Main steam lines, reheat piping, and superheater tubes in thermal power plants.

Petrochemical & Refining: High-temperature furnace tubes, heat exchangers, and catalytic cracking units.

Chemical Processing: Transporting corrosive media and high-pressure chemical reactions.

Boiler Manufacturing: High-pressure boiler tubes and headers.

Oil & Gas: Downhole tools and high-sulfur environment transport.

Chemical composition

Element Grade P11 Grade P22 Grade P5 Grade P9 Grade P91
Carbon 0.05–0.15 0.05–0.15 0.15 max 0.15 max 0.08–0.12
Manganese 0.30–0.60 0.30–0.60 0.30–0.60 0.30–0.60 0.30–0.60
Phosphorus (max) 0.025 0.025 0.025 0.025 0.02
Sulfur (max) 0.025 0.025 0.025 0.025 0.01
Silicon 0.50–1.00 0.50 max 0.50 max 0.25–1.00 0.20–0.50
Chromium 1.00–1.50 2.00–2.50 4.00–6.00 8.00–9.50 8.00–9.50
Molybdenum 0.44–0.65 0.87–1.13 0.45–0.65 0.90–1.10 0.85–1.05
Vanadium ... ... ... ... 0.18–0.25


Dimention Tolerance

Nominal Pipe Size (NPS) OD Tolerance (Over) OD Tolerance (Under) Wall Thickness (WT) Tolerance Length Tolerance
Single Random (SRL) Double Random (DRL) Fixed Length
1/8" to 1-1/2" +0.4 mm (1/64") -0.8 mm (1/32") -12.5% (Min. Wall) ± 500mm ± 500mm +6mm / -0mm
Over 1-1/2" to 4" +0.8 mm (1/32") -0.8 mm (1/32") -12.5% (Min. Wall)
Over 4" to 8" +1.6 mm (1/16") -0.8 mm (1/32") -12.5% (Min. Wall)
Over 8" to 18" +2.4 mm (3/32") -0.8 mm (1/32") -12.5% (Min. Wall)
Over 18" to 36" +3.2 mm (1/8") -0.8 mm (1/32") -12.5% (Min. Wall)

Mechanical properties

Property P11, P22, P5, P9 Grade P91 Grade P92
Tensile Strength (min) 415 MPa (60 ksi) 585 MPa (85 ksi) 620 MPa (90 ksi)
Yield Strength (min) 205 MPa (30 ksi) 415 MPa (60 ksi) 440 MPa (64 ksi)
Elongation (Longitudinal) 30% 20% 20%
Hardness (max) 163 HB / 85 HRB 250 HB / 25 HRC 250 HB / 25 HRC

SPECIFICATION STANDARD (STEEL PIPE)

Normal Diameter OD(MM) WALL THICKMESS(MM)
ANSI B36.10M ANSI B36.19M
A(MM) B(INCH) ASME SCH5/5S SCH10S SCH10 SCH20 SCH30 STD SCH40 SCH40S SCH60 XS SCH80 SCH80S SCH100 SCH120 SCH140 SCH160 XXS
15 1/2" 21.34 1.65 2.11 2.11   2.41 2.77 2.77 2.77   3.73 3.73 3.73       4.78 7.47
20 3/4" 26.67 1.65 2.11 2.11   2.41 2.87 2.87 2.87   3.91 3.91 3.91       5.56 7.82
25 1" 33.40 1.65 2.77 2.77   2.9 3.38 3.38 3.38   4.55 4.55 4.55       6.35 9.09
32 1.1/4" 42.16 1.65 2.77 2.77   2.97 3.56 3.56 3.56   4.85 4.85 4.85       6.35 9.7
40 1.1/2" 48.26 1.65 2.77 2.77   3.18 3.68 3.68 3.68   5.08 5.08 5.08       7.14 10.15
50 2" 60.32 1.65 2.77 2.77   3.18 3.91 3.91 3.91   5.54 5.54 5.54       8.74 11.07
65 2.1/2" 73.02 2.11 3.05 3.05   4.78 5.16 5.16 5.16   7.01 7.01 7.01       9.53 14.02
80 3" 88.90 2.11 3.05 3.05   4.78 5.49 5.49 5.49   7.62 7.62 7.62       11.13 15.25
90 3.1/2" 101.60 2.11 3.05 3.05   4.78 5.74 5.74 5.74   8.08 8.08 8.08          
100 4" 114.30 2.11 3.05 3.05   4.78 6.02 6.02 6.02   8.56 8.56 8.56   11.13   13.49 17.12
125 5" 141.30 2.77 3.40 3.40     6.55 6.55 6.55   9.53 9.53 9.53   12.7   15.88 19.05
150 6" 168.28 2.77 3.40 3.40     7.11 7.11 7.11   10.97 10.97 10.97   14.27   18.26 21.95
200 8" 219.08 2.77 3.76 3.76 6.35 7.04 8.18 8.18 8.18 10.31 12.7 12.7 12.7 15.09 18.26 20.62 23.01 22.23
250 10" 273.05 3.40 4.19 4.19 6.35 7.8 9.27 9.27 9.27 12.7 12.7 15.09 12.7 18.26 21.44 25.4 28.58 25.4
300 12" 323.85 3.96 4.57 4.57 6.35 8.38 9.53 10.31 9.53 14.27 12.7 17.48 12.7 21.44 25.4 28.58 33.32 25.4
350 14" 355.60 3.96 4.78 6.35 7.92 9.53 9.53 11.13 9.53 15.09 12.7 19.05 12.7 23.83 27.79 31.75 35.71  
400 16" 406.40 4.19 4.78 6.35 7.92 9.53 9.53 12.7 9.53 16.66 12.7 21.44 12.7 26.19 30.96 36.53 40.49  
450 18" 457.20 4.19 4.78 6.35 7.92 11.13 9.53 14.27 9.53 19.05 12.7 23.83 12.7 29.36 34.93 39.67 45.24  
500 20" 508.00 4.78 5.54 6.35 9.53 12.7 9.53 15.09 9.53 20.62 12.7 26.19 12.7 32.54 38.1 44.45 50.01  
550 22" 558.80 4.78 5.54 6.35 9.53 12.7 9.53     22.23 12.7 28.58   34.93 41.28 47.63 53.98  
600 24" 609.60 5.54 6.35 6.35 9.53 14.27 9.53 17.48 9.53 24.61 12.7 30.96 12.7 38.89 46.02 52.37 59.54  
650 26" 660.40     7.92 12.7   9.53       12.7              
700 28" 711.20     7.92 12.7 15.88 9.53       12.7              
750 30" 762.00 6.35   7.92 12.7 15.88 9.53       12.7              
800 32" 812.00     7.92 12.7 15.88 9.53 17.48     12.7              
850 34" 863.60     7.92 12.7 15.88 9.53 17.48     12.7              
900 36" 914.40     7.92 12.7 15.88 9.53 19.05     12.7              

Alloy Smls Steel Pipe Production Process

Chemical composition

Element Grade P11 Grade P22 Grade P5 Grade P9 Grade P91
Carbon 0.05–0.15 0.05–0.15 0.15 max 0.15 max 0.08–0.12
Manganese 0.30–0.60 0.30–0.60 0.30–0.60 0.30–0.60 0.30–0.60
Phosphorus (max) 0.025 0.025 0.025 0.025 0.02
Sulfur (max) 0.025 0.025 0.025 0.025 0.01
Silicon 0.50–1.00 0.50 max 0.50 max 0.25–1.00 0.20–0.50
Chromium 1.00–1.50 2.00–2.50 4.00–6.00 8.00–9.50 8.00–9.50
Molybdenum 0.44–0.65 0.87–1.13 0.45–0.65 0.90–1.10 0.85–1.05
Vanadium ... ... ... ... 0.18–0.25


Dimention Tolerance

Nominal Pipe Size (NPS) OD Tolerance (Over) OD Tolerance (Under) Wall Thickness (WT) Tolerance Length Tolerance
Single Random (SRL) Double Random (DRL) Fixed Length
1/8" to 1-1/2" +0.4 mm (1/64") -0.8 mm (1/32") -12.5% (Min. Wall) ± 500mm ± 500mm +6mm / -0mm
Over 1-1/2" to 4" +0.8 mm (1/32") -0.8 mm (1/32") -12.5% (Min. Wall)
Over 4" to 8" +1.6 mm (1/16") -0.8 mm (1/32") -12.5% (Min. Wall)
Over 8" to 18" +2.4 mm (3/32") -0.8 mm (1/32") -12.5% (Min. Wall)
Over 18" to 36" +3.2 mm (1/8") -0.8 mm (1/32") -12.5% (Min. Wall)

Mechanical properties

Property P11, P22, P5, P9 Grade P91 Grade P92
Tensile Strength (min) 415 MPa (60 ksi) 585 MPa (85 ksi) 620 MPa (90 ksi)
Yield Strength (min) 205 MPa (30 ksi) 415 MPa (60 ksi) 440 MPa (64 ksi)
Elongation (Longitudinal) 30% 20% 20%
Hardness (max) 163 HB / 85 HRB 250 HB / 25 HRC 250 HB / 25 HRC

SPECIFICATION STANDARD (STEEL PIPE)

Normal Diameter OD(MM) WALL THICKMESS(MM)
ANSI B36.10M ANSI B36.19M
A(MM) B(INCH) ASME SCH5/5S SCH10S SCH10 SCH20 SCH30 STD SCH40 SCH40S SCH60 XS SCH80 SCH80S SCH100 SCH120 SCH140 SCH160 XXS
15 1/2" 21.34 1.65 2.11 2.11   2.41 2.77 2.77 2.77   3.73 3.73 3.73       4.78 7.47
20 3/4" 26.67 1.65 2.11 2.11   2.41 2.87 2.87 2.87   3.91 3.91 3.91       5.56 7.82
25 1" 33.40 1.65 2.77 2.77   2.9 3.38 3.38 3.38   4.55 4.55 4.55       6.35 9.09
32 1.1/4" 42.16 1.65 2.77 2.77   2.97 3.56 3.56 3.56   4.85 4.85 4.85       6.35 9.7
40 1.1/2" 48.26 1.65 2.77 2.77   3.18 3.68 3.68 3.68   5.08 5.08 5.08       7.14 10.15
50 2" 60.32 1.65 2.77 2.77   3.18 3.91 3.91 3.91   5.54 5.54 5.54       8.74 11.07
65 2.1/2" 73.02 2.11 3.05 3.05   4.78 5.16 5.16 5.16   7.01 7.01 7.01       9.53 14.02
80 3" 88.90 2.11 3.05 3.05   4.78 5.49 5.49 5.49   7.62 7.62 7.62       11.13 15.25
90 3.1/2" 101.60 2.11 3.05 3.05   4.78 5.74 5.74 5.74   8.08 8.08 8.08          
100 4" 114.30 2.11 3.05 3.05   4.78 6.02 6.02 6.02   8.56 8.56 8.56   11.13   13.49 17.12
125 5" 141.30 2.77 3.40 3.40     6.55 6.55 6.55   9.53 9.53 9.53   12.7   15.88 19.05
150 6" 168.28 2.77 3.40 3.40     7.11 7.11 7.11   10.97 10.97 10.97   14.27   18.26 21.95
200 8" 219.08 2.77 3.76 3.76 6.35 7.04 8.18 8.18 8.18 10.31 12.7 12.7 12.7 15.09 18.26 20.62 23.01 22.23
250 10" 273.05 3.40 4.19 4.19 6.35 7.8 9.27 9.27 9.27 12.7 12.7 15.09 12.7 18.26 21.44 25.4 28.58 25.4
300 12" 323.85 3.96 4.57 4.57 6.35 8.38 9.53 10.31 9.53 14.27 12.7 17.48 12.7 21.44 25.4 28.58 33.32 25.4
350 14" 355.60 3.96 4.78 6.35 7.92 9.53 9.53 11.13 9.53 15.09 12.7 19.05 12.7 23.83 27.79 31.75 35.71  
400 16" 406.40 4.19 4.78 6.35 7.92 9.53 9.53 12.7 9.53 16.66 12.7 21.44 12.7 26.19 30.96 36.53 40.49  
450 18" 457.20 4.19 4.78 6.35 7.92 11.13 9.53 14.27 9.53 19.05 12.7 23.83 12.7 29.36 34.93 39.67 45.24  
500 20" 508.00 4.78 5.54 6.35 9.53 12.7 9.53 15.09 9.53 20.62 12.7 26.19 12.7 32.54 38.1 44.45 50.01  
550 22" 558.80 4.78 5.54 6.35 9.53 12.7 9.53     22.23 12.7 28.58   34.93 41.28 47.63 53.98  
600 24" 609.60 5.54 6.35 6.35 9.53 14.27 9.53 17.48 9.53 24.61 12.7 30.96 12.7 38.89 46.02 52.37 59.54  
650 26" 660.40     7.92 12.7   9.53       12.7              
700 28" 711.20     7.92 12.7 15.88 9.53       12.7              
750 30" 762.00 6.35   7.92 12.7 15.88 9.53       12.7              
800 32" 812.00     7.92 12.7 15.88 9.53 17.48     12.7              
850 34" 863.60     7.92 12.7 15.88 9.53 17.48     12.7              
900 36" 914.40     7.92 12.7 15.88 9.53 19.05     12.7              

Alloy Smls Steel Pipe Production Process

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alloy seamless steel pipe,alloy steel pipe,ASTM A335 pipe,chrome moly pipe,P11 pipe,P22 pipe,P91 pipe

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