Alloy Steel Seamless Pipes Manufacturer in India
Alloy Steel Seamless Pipes Manufacturer in India
Sachiya Steel International is a trusted Alloy Steel Seamless Pipes Manufacturer in India, with 20+ years of experience serving customers across 85+ countries. We supply stainless steel, duplex, super duplex, carbon steel, alloy steel, and nickel alloy pipes and tubes for oil & gas, chemical, power, marine, pharmaceutical, construction, and engineering applications.
We manufacture and supply products to ASTM, ASME, ANSI, DIN, and ISO standards, with inspection, testing, and material documentation available as required. We support EPC contractors, manufacturers, fabricators, distributors, and procurement teams with standard, bulk, and project orders. Our focus stays on quality, material traceability, technical compliance, competitive solutions, and timely delivery worldwide
What Are Alloy Steel Seamless Pipes?
Alloy steel seamless pipes are pipes made from alloy steel and manufactured without a welded seam. They contain elements such as chromium, molybdenum, nickel, or manganese to improve strength, hardness, corrosion resistance, and performance at high temperatures and pressures.
These pipes are widely used in demanding industries where reliable performance is important. Their seamless construction provides consistent strength and helps them handle high-pressure service. Common applications include oil and gas, petrochemical, power generation, chemical processing, boilers, heat exchangers, and engineering systems.
Alloy steel seamless pipes are available in different grades, sizes, wall thicknesses, and specifications to suit specific operating conditions. They can also be supplied according to standards such as ASTM, ASME, and other applicable specifications.
Alloy Steel Seamless Pipes
High-quality alloy steel seamless pipes manufactured for demanding applications across oil & gas, petrochemical, chemical, power generation, engineering and construction industries. Available in multiple grades, sizes, wall thicknesses and manufacturing specifications.
Types of Alloy Steel Seamless Pipes
Alloy steel seamless pipes come in different types based on their grade, composition, and intended application. As an alloy steel seamless pipe manufacturer, we supply options for high-pressure, high-temperature, and demanding industrial services.
- Chromium-Molybdenum Seamless Pipes: Suitable for high-temperature and pressure applications in power and petrochemical plants.
- Chrome Moly Seamless Pipes: Known for good strength and heat resistance, commonly used in boilers and process piping.
- Nickel Alloy Steel Seamless Pipes: Offer improved toughness and performance in challenging environments.
- Low Alloy Steel Seamless Pipes: Provide a balance of strength, toughness, and cost for industrial applications.
- High Alloy Steel Seamless Pipes: Designed for applications requiring enhanced resistance to heat, corrosion, or wear.
- Boiler and Heat Exchanger Seamless Pipes: Used in systems that operate under high temperature and pressure.
ASTM A335 P11 Pipes, P22 Pipes, P5 and P9 Pipes, P91 and P92 Pipes, Low Temperature Alloy Steel Pipes, Alloy Steel Seamless Pipes Manufacturers and Suppliers in India
Project engineers rank alloy steel seamless pipes manufacturers in India by one test: can they match a grade to a temperature and prove it on paper? We roll and heat treat alloy pipes at our facility near Mumbai, hold common grades and schedules in ready stock, and cut, bevel, and mark to your drawing.
For boiler and steam piping, our P11 and P22 pipes carry the load. For refinery lines that see sulphur and hydrogen, our P5 and P9 pipes take over. For main steam and hot reheat lines, where wall thickness drives cost, our P91 and P92 pipes give the same pressure with a thinner wall than P22. For cold plants, our A333 Gr. 3, 7, and 8 pipes stay tough far below zero.
The best alloy steel seamless pipes suppliers treat the pipe and its documents as a single product. Ours arrive with a heat treatment record, a hardness record for the creep-strength grades, a PMI result, and a mill certificate that ties each length to its melt. Pricing follows alloy surcharges, grade, wall, and quantity, so we quote against the schedule you send.
Types of Pipes & Tubes
Explore our range of industrial pipes and tubes, manufactured for different applications, materials, specifications and engineering requirements.
Pipes and Tubes
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Seamless Pipes
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ERW Pipes
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LSAW Pipes
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SSAW Pipes
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Welded Pipes
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Welded Tubes
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Box Pipes
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Box Tubes
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Brass Pipes
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Heat Exchanger Tubes
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Boiler Tubes
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Aluminium Pipes
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Carbon Steel Seamless Pipes
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Carbon Steel Pipe
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Stainless Steel Pipe
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Alloy Steel Pipe
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Duplex Steel Pipe
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Super Duplex Steel Pipe
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Nickel Alloy Pipe
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Copper Nickel Alloy Pipe
→Get Certified Alloy Steel Seamless Pipes at Competitive Factory Prices
Alloy Steel Seamless Pipes Specification
| Item | Range | Remark |
|---|---|---|
| Size Range | 1/2" to 24" NPS (21.3 mm to 610 mm OD) | Larger sizes on request |
| Wall Thickness | SCH 40, 60, 80, 100, 120, 140, 160, XXS; up to about 60 mm | Nominal or minimum wall as ordered |
| Process | Hot finished, cold drawn for small bores | Cold drawn gives tighter tolerance |
| Grades | A335 P1, P2, P5, P9, P11, P12, P22, P91, P92; A333 Gr. 3, 7, 8 | Other grades on request |
| Heat Treatment | Normalised and tempered; P91 and P92 normalised at the specified temperature and tempered | The treatment sets strength and grain |
| Length | Single random 16–22 ft, double random 36–40 ft, 6 m, 12 m, exact cut | Cut lengths reduce site waste |
| Ends | Plain, bevelled 37.5° with root face, threaded | Bevels suit butt welding |
| Surface | Black, varnished, shot blasted, pickled | Varnish protects in storage |
| Tests | Hydrostatic or NDE, flattening, bend, tensile, hardness, PMI, Charpy (A333), ultrasonic on request | Hardness is mandatory for P91 and P92 |
| Papers | EN 10204 3.1 certificate; 3.2 with inspector's signature | Heat treatment chart included on request |
Alloy Steel Seamless Pipe Standards and Specifications
| Job | Standard | What It Sets |
|---|---|---|
| High-temperature seamless ferritic alloy pipe | ASTM A335 / ASME SA335 | Grades P1 to P92, chemistry, strength, tests |
| Low-temperature seamless alloy and carbon pipe | ASTM A333 / ASME SA333 | Gr. 3, 7, 8, with Charpy impact tests |
| Seamless alloy pipe for boiler and steam use | ASTM A369 | Forged and bored pipe, grades FP1 to FP92 |
| General requirements for pipe | ASTM A530, ASTM A999 | Tolerances, tests, marking |
| Dimensions and weights | ASME B36.10M | OD and wall for each NPS and schedule |
| European seamless pipe for elevated temperature | EN 10216-2 | 16Mo3, 13CrMo4-5, 10CrMo9-10, X10CrMoVNb9-1 |
| Power piping and process piping codes | ASME B31.1, B31.3, B31.4 | Design, wall calculation, joint rules |
| Welding qualification | ASME Section IX | P-numbers, procedures, welder approval |
| Pressure equipment | PED 2014/68/EU | Conformity for European projects |
| Sour service | NACE MR0175 / ISO 15156 | Hardness limits for H2S |
| Certificates | EN 10204 3.1, 3.2 | Mill and inspector-signed documents |
Alloy Steel Seamless Pipes Material and Grades
| Grade | UNS | Nominal Alloy | EN Equivalent | Typical Use |
|---|---|---|---|---|
| P1 | K11522 | 0.5Mo | 16Mo3 (1.5415) | Low-pressure steam, older boilers |
| P2 | K11547 | 0.5Cr-0.5Mo | – | Boiler tubing, steam lines |
| P5 | K41545 | 5Cr-0.5Mo | 12CrMo19-5 (1.7362) | Refinery lines, sulphur service |
| P9 | S50400 | 9Cr-1Mo | X11CrMo9-1 (1.7386) | Refinery lines, high-temperature streams |
| P11 | K11597 | 1.25Cr-0.5Mo | Closest: 13CrMo4-5 | Boiler piping, superheater headers |
| P12 | K11562 | 1Cr-0.5Mo | 13CrMo4-5 (1.7335) | Boiler and steam piping |
| P22 | K21590 | 2.25Cr-1Mo | 10CrMo9-10 (1.7380) | Steam lines, hydrogen service, heaters |
| P91 | K91560 | 9Cr-1Mo-V-Nb | X10CrMoVNb9-1 (1.4903) | Main steam, hot reheat |
| P92 | K92460 | 9Cr-2W-Mo-V-Nb-B | X10CrWMoVNb9-2 (1.4901) | Ultra-supercritical steam lines |
| A333 Gr. 3 | K31918 | 3.5Ni | – | Cold service to -101°C |
| A333 Gr. 7 | K21903 | 2.5Ni | – | Cold service to -101°C |
| A333 Gr. 8 | K81340 | 9Ni | – | Cryogenic service to -196°C |
What Is the Difference Between P11, P22 and P91 Alloy Steel Seamless Pipes?
The three grades sit on a ladder of temperature and cost. P11 holds 1.25% chromium and 0.5% molybdenum, so it handles moderate steam and costs the least. P22 holds 2.25% chromium and 1% molybdenum, so it handles hotter steam and hydrogen. P91 holds 9% chromium and adds vanadium and niobium, so it handles the hottest steam with a much thinner wall.
That thinner wall changes everything. For the same pressure and temperature, a P91 pipe often needs a wall about 40% to 50% thinner than P22, which cuts weight, reduces thermal stress, and speeds up start-ups. The trade is weld care. P91 demands tight control of preheat, interpass temperature, and post-weld heat treatment, plus a hardness check, because a poor weld loses its creep strength.
| Point | P11 | P22 | P91 |
|---|---|---|---|
| Nominal Alloy | 1.25Cr-0.5Mo | 2.25Cr-1Mo | 9Cr-1Mo-V-Nb |
| Typical Metal Temperature | Up to about 550°C | Up to about 580°C | Up to about 620°C |
| Creep Strength | Basic | Good | Very high |
| Wall for the Same Duty | Thickest | Thick | Thin |
| ASME P-Number | P-No. 4 | P-No. 5A | P-No. 15E |
| Welding Care | Preheat and PWHT | Preheat and PWHT | Tight control of heat input, preheat, and PWHT |
| Hardness Check | Not specified in A335 | Not specified in A335 | 250 HBW max |
| Hydrogen Service | Limited | Good | Not typical |
| Relative Cost | Lowest | Medium | Highest per kg, often lower per metre of pipe |
| Typical Home | Boiler piping | Steam lines, heaters, hydrogen units | Main steam, hot reheat |
Alloy Steel Seamless Pipes Chemical Composition
Chemistry decides creep strength, oxidation resistance, and weldability. Values are weight percent, maximum unless a range shows.
Chrome-Moly Grades (ASTM A335)
| Grade | C | Mn | Si | Cr | Mo | Other |
|---|---|---|---|---|---|---|
| P1 | 0.10–0.20 | 0.30–0.80 | 0.10–0.50 | – | 0.44–0.65 | – |
| P2 | 0.10–0.20 | 0.30–0.61 | 0.10–0.30 | 0.50–0.81 | 0.44–0.65 | – |
| P5 | 0.15 | 0.30–0.60 | 0.50 | 4.00–6.00 | 0.45–0.65 | – |
| P9 | 0.15 | 0.30–0.60 | 0.25–1.00 | 8.00–10.00 | 0.90–1.10 | – |
| P11 | 0.05–0.15 | 0.30–0.60 | 0.50–1.00 | 1.00–1.50 | 0.44–0.65 | – |
| P12 | 0.05–0.15 | 0.30–0.61 | 0.50 | 0.80–1.25 | 0.44–0.65 | – |
| P22 | 0.05–0.15 | 0.30–0.60 | 0.50 | 1.90–2.60 | 0.87–1.13 | – |
| P91 | 0.08–0.12 | 0.30–0.60 | 0.20–0.50 | 8.00–9.50 | 0.85–1.05 | V 0.18–0.25, Nb 0.06–0.10, N 0.03–0.07, Ni 0.40, Al 0.02 |
| P92 | 0.07–0.13 | 0.30–0.60 | 0.50 | 8.50–9.50 | 0.30–0.60 | W 1.50–2.00, V 0.15–0.25, Nb 0.04–0.09, N 0.03–0.07, B 0.001–0.006, Ni 0.40 |
All grades above hold P at 0.025 max and S at 0.025 max, except P91 and P92, which hold P at 0.020 max and S at 0.010 max.
Low-Temperature Nickel Grades (ASTM A333)
| Grade | C | Mn | Si | Ni | P / S (max) |
|---|---|---|---|---|---|
| Gr. 3 | 0.19 | 0.31–0.64 | 0.18–0.37 | 3.18–3.82 | 0.025 / 0.025 |
| Gr. 7 | 0.19 | 0.90 | 0.13–0.32 | 2.03–2.57 | 0.025 / 0.025 |
| Gr. 8 | 0.13 | 0.90 | 0.13–0.32 | 8.40–9.60 | 0.025 / 0.025 |
Alloy Steel Seamless Pipes Mechanical Properties
Mechanical properties show how much load the pipe carries before it stretches (yield) or breaks (tensile). Values are minimum unless marked max.
| Grade | Tensile ksi (MPa) | Yield ksi (MPa) | Elongation % | Hardness (max) | Charpy Test Temperature |
|---|---|---|---|---|---|
| P1, P2 | 55 (380) | 30 (205) | 30 | – | – |
| P5, P9, P11, P12, P22 | 60 (415) | 30 (205) | 30 | – | – |
| P91 | 85 (585) | 60 (415) | 20 | 250 HBW | – |
| P92 | 90 (620) | 64 (440) | 20 | 250 HBW | – |
| A333 Gr. 3 | 65 (450) | 35 (240) | 30 | – | -101°C (-150°F) |
| A333 Gr. 7 | 65 (450) | 35 (240) | 30 | – | -101°C (-150°F) |
| A333 Gr. 8 | 100 (690) | 75 (520) | 22 | – | -196°C (-320°F) |
These are room-temperature minimums. A designer works from the allowable stress at metal temperature in ASME Section II Part D, which falls as temperature rises, so the usable strength at 550°C is much lower than the figures above.
Alloy Steel Seamless Pipe Size and Weight Chart
Alloy steel pipe follows the same ASME B36.10M walls as carbon steel. The chart covers the two heavy schedules that high-pressure steam lines use most. Weights are for low-alloy steel at 7.85 g/cm³. P91 and P92 weigh about 1% less.
| NPS | OD mm | SCH 80 Wall mm | SCH 80 kg/m | SCH 160 Wall mm | SCH 160 kg/m |
|---|---|---|---|---|---|
| 3" | 88.9 | 7.62 | 15.27 | 11.13 | 21.35 |
| 4" | 114.3 | 8.56 | 22.32 | 13.49 | 33.54 |
| 6" | 168.3 | 10.97 | 42.56 | 18.26 | 67.56 |
| 8" | 219.1 | 12.70 | 64.64 | 23.01 | 111.27 |
| 10" | 273.1 | 15.09 | 96.01 | 28.58 | 172.33 |
| 12" | 323.9 | 17.48 | 132.09 | 33.32 | 238.76 |
| 14" | 355.6 | 19.05 | 158.11 | 35.71 | 281.70 |
| 16" | 406.4 | 21.44 | 203.53 | 40.49 | 365.35 |
| 18" | 457.2 | 23.83 | 254.67 | 45.24 | 459.59 |
| 20" | 508.0 | 26.19 | 311.18 | 50.01 | 564.81 |
| 24" | 609.6 | 30.96 | 441.78 | 59.54 | 807.63 |
To work out the weight of any size, use Weight (kg/m) = (OD − Wall) × Wall × 0.02466, with both values in mm.
Common Alloy Steel Seamless Pipe Materials
As an alloy steel seamless pipe supplier, we offer common grades used in high-temperature, high-pressure, and industrial piping systems. The grade identifies the alloy composition and helps determine the pipe’s performance, welding requirements, and suitable application.
P11: Contains about 1.25% chromium and 0.5% molybdenum. Commonly used in boilers, refineries, and high-temperature piping.
P22: Contains about 2.25% chromium and 1% molybdenum. It offers good strength and heat resistance for power and petrochemical systems.
P91: A modified 9% chromium steel with vanadium and niobium, designed for demanding high-temperature service.
P92: A modified 9% chromium grade that also contains tungsten for improved high-temperature performance.
16Mo3: A European boiler and pressure-vessel steel used under EN 10216-2.
13CrMo4-5: A chromium-molybdenum steel suited for elevated-temperature applications.
10CrMo9-10: Used for high-temperature and pressure service, particularly in power plants.
X10CrMoVNb9-1: A P91-equivalent European grade for demanding power-generation applications.
When ordering, specify the grade, standard, delivery condition, and wall thickness basis to ensure the pipe matches your application and welding requirements.
Available Sizes, Dimensions and Schedules
We supply alloy steel seamless pipes from 1/2" to 24" NPS in schedules 40, 60, 80, 100, 120, 140, 160, and XXS, with walls up to about 60 mm. A schedule is a wall-thickness code, so the same schedule gives a different wall in mm at each pipe size, and the outside diameter stays fixed for each NPS. High-pressure steam lines often use thick walls that fall between standard schedules, so we also roll pipes to an exact OD and wall.
Decide early whether you order by nominal wall or minimum wall. ASTM A335 allows the mill to deliver up to 12.5% under the nominal wall, so a designer working from a minimum wall should order a minimum-wall pipe or raise the nominal wall to cover the tolerance. Standard lengths are single random (16–22 ft) and double random (36–40 ft). We also cut 6 m, 12 m, and exact lengths, and we hold common grades in stock, subject to availability.
| Product | Size Range | Walls | Lengths | Condition |
|---|---|---|---|---|
| ASTM A335 P11 / P12 Pipes | 1/2" to 24" NPS | SCH 40 to XXS | Random / 6 m / 12 m / cut | Normalised and tempered |
| ASTM A335 P22 Pipes | 1/2" to 24" NPS | SCH 40 to XXS | Random / 6 m / 12 m / cut | Normalised and tempered |
| ASTM A335 P5 / P9 Pipes | 1/2" to 20" NPS | SCH 40 to XXS | Random / 6 m / 12 m / cut | Annealed or normalised and tempered |
| ASTM A335 P91 / P92 Pipes | 2" to 20" NPS | SCH 80 to SCH 160 and thick walls | Random / 6 m / 12 m / cut | Normalised and tempered |
| ASTM A333 Gr. 3 / 7 / 8 Pipes | 1/2" to 20" NPS | SCH 40 to SCH 160 | Random / 6 m / 12 m / cut | Normalised or quenched and tempered |
| Cold Drawn Alloy Pipes | 1/4" to 6" OD | Thin to medium | 6 m / cut | Annealed or normalised |
Alloy Steel Seamless Pipes We Manufacture and Supply
| Product | Grades | Standard | Common Finish |
|---|---|---|---|
| Boiler and Steam Piping | P11, P12, P22 | ASTM A335 | Black or varnished |
| Refinery and Sulphur-Service Piping | P5, P9 | ASTM A335 | Black or varnished |
| Main Steam and Hot Reheat Piping | P91, P92 | ASTM A335 | Shot blasted or varnished |
| Low-Temperature and Cryogenic Piping | Gr. 3, 7, 8 | ASTM A333 | Black or pickled |
| European-Standard Pressure Pipes | 16Mo3, 13CrMo4-5, 10CrMo9-10, X10CrMoVNb9-1 | EN 10216-2 | Black or varnished |
| Cut-to-Length and Bevelled Spools | P11, P22, P91 | ASTM A335 | Bevelled, capped |
Each shipment carries the heat numbers, heat treatment records, hardness results, and test reports your standard requires.
Applications of Alloy Steel Seamless Pipes
- Thermal Power Plants: Carry main steam, hot reheat, and feedwater at high temperature and pressure.
- Boiler Headers and Superheater Piping: Connect boiler sections that run hot.
- Refineries and Hydrocrackers: Handle hot hydrogen, sulphur, and hydrocarbons.
- Petrochemical Plants: Serve furnace piping and high-temperature process lines.
- Fired Heater Coils: Withstand direct flame heat and creep.
- Fertilizer Plants: Carry hot gas in ammonia and urea units.
- LNG, Ethylene, and Cryogenic Plants: Stay tough at -101°C to -196°C with A333 grades.
- Combined Cycle and Heat Recovery Plants: Carry steam between gas turbines and steam turbines.
- Steam Distribution Networks: Move high-pressure steam across industrial sites.
Why Choose Us as Your Alloy Steel Seamless Pipes Manufacturer in India?
With 20+ years of experience, we know what industrial buyers expect from alloy steel seamless pipes. We manufacture and supply grades such as P11, P22, P91, P92, P5, P9, 16Mo3, 13CrMo4-5, and 10CrMo9-10 in different sizes, wall thicknesses, and specifications. We can handle 100+ tons of alloy steel seamless pipes every month, supporting both regular and bulk project requirements.
We export to 85+ countries and work with EPC contractors, distributors, fabricators, and industrial buyers worldwide. Our capabilities cover standard and custom requirements, with support for ASTM, ASME, EN, and other applicable standards. We focus on material traceability, inspection, documentation, proper packing, and dependable delivery, giving customers a reliable source for alloy steel seamless pipes from India.
Countries We Export Alloy Steel Seamless Pipes To
We export alloy steel seamless pipes to customers in 85+ countries, supporting industrial projects, distributors, EPC contractors, fabricators, and engineering companies with regular and bulk requirements. Our export reach covers key markets across North America, the Middle East, Europe, Asia Pacific, Africa, and South America.
North America: United States, Canada, Mexico
Middle East: UAE, Saudi Arabia, Qatar, Kuwait, Oman, Bahrain
Europe: UK, Germany, France, Italy, Netherlands, Spain
Asia Pacific: Australia, Singapore, Malaysia, Indonesia, Thailand, Vietnam
Africa: South Africa, Egypt, Nigeria, Kenya, Algeria
South America: Brazil, Argentina, Chile, Peru, Colombia
Alloy Steel Seamless Pipes FAQs
Common questions about alloy steel seamless pipe grades, heat treatment, dimensions, welding, and supply.
Which grade should I choose for a main steam line?
For modern high-pressure lines, designers usually choose P91 or P92, because they allow a thinner wall than P22. For moderate steam conditions, P22 or P11 may do the job at a lower first cost.
Can I replace P22 with P91 in an existing line?
Often yes, but not as a simple swap. P91 changes wall thickness, thermal expansion behaviour, weld procedures, and heat treatment, so the design engineer must approve it under the project code.
Why does P91 need such careful welding?
P91 gets its creep strength from a fine microstructure. Too much heat input, the wrong preheat, or the wrong post-weld heat treatment destroys that structure and leaves a weak zone, which is why codes demand tight control and a hardness check.
Do alloy steel pipes need heat treatment after welding?
Yes. Chrome-moly steels need post-weld heat treatment to temper the weld and relieve stress. The temperature and time depend on the grade and thickness, and your weld procedure and code set the figures.
Is alloy steel pipe suitable for hydrogen service?
Chrome-moly grades such as P11, P22, and P5 resist hot hydrogen attack better than carbon steel. Designers choose the grade from the operating temperature and hydrogen pressure on the Nelson curves.
Can alloy steel seamless pipes handle low temperature?
The nickel grades can. ASTM A333 Gr. 3 and Gr. 7 serve down to -101°C, and Gr. 8 serves down to -196°C. Chrome-moly A335 grades are for heat, not for cold.
Do alloy steel pipes need IBR approval in India?
Pipes used in boilers governed by the Indian Boiler Regulations need IBR-approved material. Tell us at enquiry stage, and we will confirm the certification route before we quote.
Should I order by nominal wall or minimum wall?
Order by minimum wall when the design calculation uses a minimum wall. ASTM A335 allows up to 12.5% under the nominal wall, so a nominal-wall order can arrive thinner than the design needs.
What sizes do your alloy steel seamless pipes come in?
We supply pipes from 1/2" to 24" NPS in schedules 40 to XXS, with walls up to about 60 mm. Other sizes and exact OD and wall combinations are available on request.
What shapes the price of alloy steel seamless pipes?
Alloy surcharges for chromium, molybdenum, nickel, and vanadium move the price first. Then come grade, wall, heat treatment, quantity, and delivery port. Send your schedule, and we quote against it.
Which certificates come with the pipes?
Each lot carries an EN 10204 3.1 mill certificate. A 3.2 certificate is available when an independent inspector co-signs, and heat treatment charts are available on request.
Are you an alloy steel seamless pipes manufacturer or a supplier?
We are both. We make the pipes and also work as an alloy steel seamless pipes supplier in India, with ready stock of common grades.
Do you ship alloy steel seamless pipes overseas?
Yes, to 85+