Monel 400 Pipe
Steel Pipe & Tubes has been a leading supplier of Monel piping solutions.
Monel 400 Pipe is a critical material in industries where durability, corrosion resistance and mechanical strength cannot be compromised. This nickel-copper alloy (UNS N04400) excels in harsh environments such as seawater, chemical processing and offshore applications, making it indispensable for high-stakes operations. Trusted by engineers and metallurgists worldwide, every Monel 400 seamless and welded pipe we supply meets ASTM B164 and ASME SB725 standards, with full heat-traceability and certification. Its exceptional resistance to pitting, stress-corrosion cracking and high-temperature oxidation ensures long-lasting performance, reliability, and safety, highlighting why Monel 400 remains a cornerstone material for critical industrial infrastructure.
Best Monel 400 Pipe Manufacturer in India - Alloy UNS N04400 Tubing Supplier
What Are Monel 400 Pipes / Tubes?
Monel 400 Pipes and Tubes are manufactured from a nickel–copper alloy known for its excellent strength, durability, and resistance to corrosive environments. The alloy, designated as UNS N04400 / WNR 2.4360, typically contains about 63% nickel and 28–34% copper, along with controlled amounts of iron, manganese, and other trace elements. This unique composition gives Monel 400 its ability to perform reliably in harsh conditions where many other alloys fail.
Monel 400 Pipes are widely supplied in both seamless and welded forms, designed to meet ASTM B165 / B725 and ASME SB165 / SB725 standards. Seamless pipes are produced through hot extrusion and cold drawing processes to achieve excellent dimensional accuracy and strength, while welded pipes are fabricated using advanced welding techniques for larger diameters and cost-effective installations. Tubes are also available in a wide range of outside diameters and wall thicknesses, ensuring suitability for both high-pressure systems and precision instrumentation.
These pipes and tubes are valued for their ability to maintain toughness across a broad temperature range, from cryogenic service up to about 500 °C. Their versatility, coupled with excellent fabrication and welding properties, makes Monel 400 Pipes and Tubes an indispensable choice for demanding service environments in marine, chemical, refining, and power sectors.
Types of Monel 400 Pipe
Monel 400 is available in several forms of pipes and tubes, each designed to meet specific operational requirements. The table below summarizes the major types along with their characteristics and typical applications.
Monel 400 Pipe
UNS N04400 Welded Pipe
Monel 400 Seamless Pipe
Monel 400 Pipe Specifications
To meet diverse industrial requirements, Monel 400 Pipes and Tubes are manufactured under strict international standards with precise dimensional accuracy and controlled chemical composition. The specifications below highlight the commonly supplied forms, sizes, and finishes offered by Stellar Alloys.
| Standard | ASTM B165 / ASTM B725 / ASME SB165 / SB725 |
| Grade | Monel 400 / UNS N04400 / WNR 2.4360 |
| Type | Seamless, Welded, ERW, Fabricated |
| Size Range | ½” to 24” NB (custom available) |
| Form | Round, Square, Rectangular, Hydraulic, Bush, Hexagonal |
| Length | Single Random, Double Random, Cut Length |
| Ends | Plain End, Beveled End, Threaded |
| Surface Finish | Annealed, Pickled, Polished, Bright Annealed |
Available Size Range of Monel 400 Pipes
Monel 400 Pipes and Tubes are supplied in a variety of diameters, wall thicknesses, and lengths to suit different project requirements. The table below provides a quick overview of the commonly available size ranges.
| Product Type | Size Range | Wall Thickness (WT) | Length |
| Seamless Pipes | ½” NB to 8” NB | 0.5 mm – 20 mm | Up to 12 m (custom cut available) |
| Welded Pipes | ½” NB to 24” NB | 0.5 mm – 20 mm | Single / Double Random, Cut Length |
| Seamless Tubes | OD 6.35 mm – 114.3 mm | 0.5 mm – 12 mm | Up to 12 m |
| Welded Tubes | OD 6.35 mm – 168.3 mm | 0.5 mm – 20 mm | Standard & Custom Lengths |
ASTM B165 UNS N04400 Tube Dimensions & Thickness Chart
Monel 400 Tubes are manufactured in a wide range of outside diameters (OD) and wall thicknesses (WT) to meet ASTM B165 standards. The following chart shows some of the most commonly supplied dimensions for seamless and welded tubes.
| OD (mm) | WT (mm) | OD (inch) | WT (inch) |
| 6.35 | 0.89 | 0.25 | 0.035 |
| 12.70 | 1.65 | 0.50 | 0.065 |
| 19.05 | 2.11 | 0.75 | 0.083 |
| 25.40 | 2.77 | 1.00 | 0.109 |
| 38.10 | 3.40 | 1.50 | 0.134 |
| 50.80 | 3.91 | 2.00 | 0.154 |
| 76.20 | 5.16 | 3.00 | 0.203 |
| 101.60 | 5.74 | 4.00 | 0.226 |
Pressure Ratings of ASTM B165 Monel 400 Square Pipes
The working pressure of Monel 400 Square Pipes depends on size, wall thickness, and whether the pipe is seamless or welded. The table below shows indicative pressure ratings at 38 °C (100 °F) for commonly used dimensions.
| Side × WT (mm) | Working Pressure – Seamless (bar) | Working Pressure – Welded (bar) |
| 25 × 2.0 | 380 | 325 |
| 50 × 3.0 | 260 | 220 |
| 75 × 5.0 | 430 | 370 |
| 100 × 6.0 | 510 | 440 |
Monel UNS N04400 Hollow Pipe Pressure Ratings
Monel 400 hollow pipes are used in high-pressure environments such as oil & gas, chemical processing, and marine applications. The pressure rating depends on pipe diameter, wall thickness, and whether the pipe is seamless or welded. The table below provides indicative working pressures at 38 °C (100 °F).
| OD × WT (mm) | Seamless Pressure (bar) | Welded Pressure (bar) |
| 40 × 2.5 | 290 | 250 |
| 60 × 4.0 | 410 | 350 |
| 80 × 5.0 | 520 | 460 |
Weight Chart of WNR 2.4360 Rectangular Pipes
The weight of Monel 400 (WNR 2.4360) rectangular pipes varies based on size and wall thickness. Knowing the weight per meter helps in accurate project planning, freight estimation, and structural load calculations. Below is an indicative weight chart for common sizes.
| Size (mm) | Wall Thickness (mm) | Weight (kg/m) |
| 40 × 20 | 2.0 | 2.15 |
| 60 × 40 | 3.0 | 4.90 |
| 100 × 50 | 5.0 | 12.10 |
ASME SB725 Alloy 400 Hexagonal Pipe Characteristics
Find below the detailed specifications of ASME SB725 Alloy 400 hexagonal pipes characteristics highlighting material grade, sizes, finishes and typical applications:
| Parameter | Specification / Range |
| Material Grade | Monel 400 / Alloy 400, UNS N04400, W. Nr. 2.4360 |
| Product Form | Hexagonal pipe / Hex nipple (machined from SB725 pipe or hex bar) |
| Size Range | 1/4″ – 4″ NPS; custom AF (Across Flats) sizes on request |
| Wall Thickness | Schedule 10S – Schedule 80S |
| End / Threads | NPT / BSPT male & female, bevel, plain; custom PE / BE blanks |
| Finishes | Bright annealed, pickled, polished |
| Standards | ASME SB725 for pipe; threads per ASME B1.20.1 / ISO 7/1 |
| Testing / Inspection | Hydro test, thread-gauge checks, PMI; documentation on request |
| Typical Uses | Instrumentation tie-ins, chemical dosing lines, high-temp headers, OEM skids; compact, wrench-friendly hex profile |
| Notes | Hex sections are short machined parts, not continuous mill-made; confirm AF, thread, pressure class before manufacture |
HSN Code of Monel 400 Seamless Pipe
For international trade and customs classification, Monel 400 Seamless Pipes are categorized under specific Harmonized System of Nomenclature (HSN) codes. This helps in standardized identification, taxation and global commerce. The table below provides the relevant HSN code details:
| Product | HSN Code | Description |
| Monel 400 Seamless Pipes | 75071200 | Nickel-copper alloy pipes and tubes, seamless, of nickel content >99% |
Physical Properties of DIN 2.4360 Square Pipes (Annealed Condition)
Monel 400 (WNR 2.4360) square pipes, when supplied in the annealed condition, demonstrate a combination of high strength, ductility and thermal stability. The table below highlights the key physical properties that make them suitable for use in demanding marine, chemical and power generation environments:
| Property | Value |
| Density | 8.80 g/cm³ |
| Melting Range | 1300–1350 °C |
| Elastic Modulus | 179 GPa |
| Electrical Resistivity | 5.47 µΩ·cm |
| Magnetic Permeability | 1.002 (slightly magnetic) |
Temperature Range of UNS N04400 Welded Pipe
Monel 400 welded pipes can operate reliably across a wide temperature spectrum, from sub-zero cryogenic conditions to elevated service environments. Their ability to retain mechanical strength and corrosion resistance makes them suitable for diverse industrial applications such as marine systems, chemical plants, and heat exchangers. The table below provides the indicative service temperature range:
| Condition | Service Temperature Range |
| Minimum Operating Temp. | −100 °C |
| Maximum Operating Temp. | +500 °C |
| Recommended Application Use | Cryogenic to moderately high-temperature service |
Stress Rupture Properties of Monel 400 Bright Annealed Pipes
Monel 400 bright annealed pipes are designed to retain their strength and ductility under long-term exposure to elevated temperatures and stress. Stress rupture testing helps determine the time-to-failure of the material under constant load and temperature, ensuring safe design for high-temperature applications. The table below highlights typical stress rupture values.
| Temperature (°C) | Applied Stress (MPa) | Rupture Life (hours) |
| 400 | 100 | 1000 |
| 500 | 80 | 500 |
| 600 | 60 | 200 |
Testing & Quality Standards for Nickel Alloy 400 ERW Pipes
To ensure that Nickel Alloy 400 ERW pipes meet the highest industry standards, a comprehensive testing and quality assurance program is implemented. The following checks and inspections guarantee structural integrity, material compliance and defect-free performance for critical applications:
Hydrostatic Test: Pipes are filled with pressurized water to check their ability to withstand internal pressure without leakage. This ensures the structural integrity of the pipe under working conditions. It is one of the most reliable methods to guarantee safe performance in high-pressure service.
Ultrasonic Testing (UT): High-frequency sound waves are passed through the pipe walls to detect internal flaws. The reflections are analyzed to identify cracks, voids, or inclusions that may weaken the pipe. This method is non-destructive and provides precise results without affecting pipe usability.
Eddy Current Test: An electromagnetic field is applied to the pipe surface to locate cracks and near-surface defects. Variations in the induced current highlight imperfections in conductivity or material uniformity. It is a rapid quality control method, especially effective for ERW pipes.
Radiography Test (RT): X-rays or gamma rays are used to examine welded joints for porosity, inclusions, or lack of fusion. The radiographic image clearly displays hidden weld defects that could compromise strength. This test ensures weld seams meet stringent international standards.
Positive Material Identification (PMI): Specialized analyzers check the chemical composition of the alloy against UNS N04400 requirements. This prevents material mix-ups during production and confirms nickel-copper ratios. It ensures full compliance with client specifications and international codes.
Third-Party Inspection (TPI): Reputed agencies such as SGS, Lloyd’s, or Bureau Veritas verify the pipes independently. They cross-check dimensions, material test certificates, and quality documentation. This adds an additional layer of trust and credibility for global buyers.
Most Popular Types of Monel 400 Alloy Pipes
Monel 400 alloy pipes are available in a variety of types, each engineered to meet specific industrial requirements. The following categories highlight the most commonly supplied Monel 400 pipes showcasing their distinct features, applications and performance benefits:
Monel 400 Seamless & Welded Pipes: Seamless pipes are manufactured through extrusion for high strength and leak-proof performance, while welded pipes are fabricated for larger diameters and cost efficiency. Both types provide excellent corrosion resistance in seawater, chemical, and refinery service. They are widely used where durability and reliability are critical under varying pressure conditions.
Monel 400 ERW Pipes: These pipes are made using Electric Resistance Welding, ensuring consistent wall thickness and smooth finishes. ERW pipes are lightweight, easy to install, and preferred for medium-pressure systems. Their balance of cost and performance makes them suitable for structural and utility applications.
Monel 400 Fabricated Pipes: Custom-made pipes are designed and manufactured to meet unique project specifications. They may involve bending, cutting, or welding to create tailor-made solutions. Such pipes are often supplied for specialized equipment in oil refineries, power plants, and marine systems.
Monel 400 Heat Exchanger Tubes: Designed for high thermal conductivity and corrosion resistance in heat transfer equipment. These tubes perform exceptionally in condensers, coolers, and evaporators exposed to seawater or brine. Their durability ensures extended service life with minimal maintenance.
Monel 400 Condenser Tubes: Specifically engineered for condensers handling hot gases, steam, and corrosive fluids. They resist stress-corrosion cracking and pitting, ensuring safe operation under thermal cycling. Commonly used in power generation, chemical plants, and marine condensers.
Monel 400 Instrumentation Tubes: Precision tubes used in control systems, instrumentation, and measurement devices. They maintain dimensional stability even in high-pressure and corrosive environments. Ideal for petrochemical plants, offshore platforms, and process instrumentation.
Monel 400 High-Pressure Seamless Pipes: These pipes are designed to handle very high working pressures without failure. Manufactured to exact tolerances, they are used in critical service environments. Industries such as oil & gas exploration and defense rely on them for safety and performance.
Specification Sheet of Monel 400 Bush Hex Pipes
Monel 400 Bush Hex Pipes are widely used in industries that require a combination of strength, corrosion resistance, and machinability. Their hexagonal form provides added grip and structural versatility, making them suitable for fittings, fasteners, and custom components. The table below outlines the key specifications.
| Parameter | Value |
| Material | Nickel-Copper Alloy 400 |
| Standard | ASTM B165 / ASTM B725 |
| Grade | UNS N04400 / WNR 2.4360 |
| Shape | Hexagonal / Bush Form |
| Surface Finish | Bright Annealed, Pickled, Polished |
| Lengths Available | Single Random, Double Random, Custom Cut |
| End Finish | Plain End / Beveled End / Threaded |
Latest Price List of Alloy 400 Seamless Tubes (Indicative ₹/Kg)
The cost of Monel 400 Pipes and Tubes varies depending on the type, size, finish, and order volume. Prices are generally quoted on a per-kilogram basis and may fluctuate with raw material costs, market demand, and customization requirements. The table below provides an indicative price range to help buyers plan procurement budgets.
| Product | Price Range (INR/Kg) |
| Monel 400 Seamless Pipe | ₹2,500 – ₹3,200 |
| Monel 400 Welded Pipe | ₹2,000 – ₹2,800 |
| Monel 400 Seamless Tube | ₹2,600 – ₹3,400 |
| Monel 400 Welded Tube | ₹2,100 – ₹2,900 |
| Monel 400 Hexagonal Pipe | ₹2,700 – ₹3,500 |
Why Choose Stellar Alloys for Monel 400 Pipes & Tubes?
Stellar Alloys is committed to delivering high-quality Monel 400 pipes and tubes that meet stringent industry standards. Here’s why clients across the globe rely on us for reliable precision-engineered nickel alloy solutions:
Two Decades of Expertise: With more than 20 years of experience in nickel alloys, we understand the technical requirements of critical industries. Our team works closely with engineers and procurement teams to deliver the most suitable Monel 400 solutions. This expertise ensures consistency in quality and long-term reliability.
ISO & PED Certified Manufacturing: Our facilities are certified to ISO 9001:2015, PED, and ISO 14001, ensuring global compliance. Every Monel 400 pipe and tube is manufactured under strict quality management systems. This provides assurance of international standards for safety and performance.
Comprehensive Range: We supply seamless, welded, ERW, and fabricated Monel 400 pipes in round, square, rectangular, and hexagonal forms. Multiple size ranges and custom options make us a one-stop source for varied project requirements. This wide availability reduces sourcing complexity for buyers.
Global Exports: Our strong export network covers the Middle East, Europe, Asia, and North America. With reliable logistics partners, we ensure on-time delivery anywhere in the world. This makes us a trusted supplier for both bulk and project-based orders.
MTC & Documentation: Every dispatch includes EN 10204 3.1/3.2 Mill Test Certificates and third-party inspection reports if required. Complete documentation ensures traceability and compliance with industry codes. This transparency builds confidence for EPC contractors and international clients.
Custom Solutions: We offer cut-to-length supply, special surface finishes, and protective packaging for marine export. Buyers can request project-specific modifications to meet unique operational needs. These tailored solutions help reduce fabrication time at the client’s end.
Frequently Asked Questions About Monel 400 Pipe
Monel 400 Pipes are mainly used in marine engineering, desalination plants, chemical processing, and oil refineries. Their resistance to seawater and acidic environments makes them ideal for heat exchangers, pumps, condensers, and process piping.
Monel 400 offers superior resistance to chlorides, saltwater, and non-oxidizing acids compared to stainless steel. While stainless steel is more economical, Monel 400 is chosen where long-term durability in highly corrosive environments is critical.
Monel 400 is essentially non-magnetic at room temperature, though slight magnetism can develop after cold working. This makes it suitable for applications where minimal magnetic interference is required.
Yes, Monel 400 can be welded using standard methods such as GTAW (TIG), SMAW, and GMAW. Proper filler metals and controlled welding practices are recommended to achieve strong, defect-free welds.
Industries such as shipbuilding, oil & gas, chemical plants, power generation, and aerospace rely heavily on Monel 400 Pipes. Their ability to withstand extreme temperatures, corrosive chemicals, and seawater exposure makes them indispensable.
