Introduction
ASTM B165 Monel 400 Seamless Pipe (UNS N04400) is a nickel-copper alloy pipe known for its outstanding resistance to seawater, acids, and alkaline environments. DLSS supplies seamless pipes in size 273 mm OD × 9.27 mm WT × 5200 mm length, manufactured according to ASTM B165.
These pipes are delivered with a bright surface finish and undergo 100% Hydrostatic Test (HT), Eddy Current Test (ET), and Ultrasonic Test (UT) to ensure structural integrity and defect-free performance. Monel 400 is widely used in marine, oil & gas, and chemical processing applications, especially for heat exchangers, piping systems, and offshore equipment.
What is Monel 400 (UNS N04400)?
Monel 400 is a solid-solution nickel-copper alloy containing approximately:
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Ni (≥63%)
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Cu (28–34%)
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Small amounts of Fe and Mn
Key advantages:
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Excellent resistance to seawater and steam at high temperatures
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Superior resistance to hydrofluoric acid, sulfuric acid, and alkalis
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High mechanical strength and toughness
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Non-magnetic and stable across a wide temperature range
Specifications
| Item | Details |
|---|---|
| Standard | ASTM B165 |
| Material | Monel 400 (UNS N04400) |
| Type | Seamless Pipe |
| Size | 273 mm OD × 9.27 mm WT × 5200 mm Length |
| Surface Finish | Bright Surface |
| Testing | 100% HT (Hydrostatic), ET (Eddy Current), UT (Ultrasonic) |
| Applications | Marine systems, offshore platforms, chemical processing, heat exchangers |
Key Features
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Seamless Construction – high reliability in critical service.
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Bright Surface Finish – clean, smooth inner/outer surfaces, minimizing fouling.
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Excellent Corrosion Resistance – resists seawater, acids, and alkaline solutions.
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100% Non-Destructive Testing – HT, ET, UT for guaranteed quality and safety.
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Durable Performance – proven reliability in high-temperature and corrosive environments.
Applications
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Heat Exchangers & Condensers – handling seawater and chemical media.
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Marine Engineering – seawater cooling, ship piping, offshore equipment.
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Oil & Gas Industry – sour gas piping, offshore risers, refineries.
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Chemical Processing – handling hydrofluoric acid, sulfuric acid, caustic soda.
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Power Plants – piping for high-temperature and corrosive media.
Why Choose DLSS?
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Supply of nickel alloy seamless pipes: Monel, Incoloy, Inconel, Hastelloy.
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Full NDT Assurance – 100% HT, ET, UT before shipment.
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Third-Party Inspection – SGS, BV, TUV certifications available.
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Export Packaging – plastic caps, seaworthy wrapping, ISPM-15 wooden cases.
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Proven Projects – supplied to marine, desalination, and refinery projects worldwide.
Frequently Asked Questions (FAQ)
Q1: Why choose Monel 400 for seawater service?
A1: Monel 400 resists seawater corrosion and biofouling, ensuring long service life in marine environments.
Q2: What’s the purpose of 100% HT/ET/UT?
A2: Hydrostatic, Eddy Current, and Ultrasonic Testing verify structural integrity, ensuring defect-free performance.
Q3: What is the main difference between Monel 400 and stainless steel?
A3: Monel 400 offers superior resistance to hydrofluoric acid, seawater, and alkalis, where stainless steels may fail.
Q4: Can DLSS supply custom sizes?
A4: Yes, cut-to-length, heavy-wall, and U-bend Monel pipes are available.
