MSS SP 83 B564 UNS N04400 Pipe Unions
MSS SP-83 B564 UNS N04400 Pipe Unions are pipeline quick-connect couplings compliant with the MSS SP-83 standard, manufactured from ASTM B564 UNS N04400 (Monel 400) nickel-copper alloy. Designed for highly corrosive environments (e.g., seawater, acidic media) and high-temperature/pressure systems, they are widely used in chemical processing, offshore engineering, oil & gas, and other demanding industries.
High Quality MSS SP 83 B564 UNS N04400 Pipe Unions
- Pressure Rating: Class 3000 (~750 psi) and 6000 (~1500 psi)
- Size Range: typically NPS 1/8″ to 4″
- Types: Socket weld (SW), Threaded (NPT)
Key Features
Corrosion Resistance:
- Nearly immune to chloride-induced corrosion (e.g., seawater) and acidic media, outperforming stainless steel.
- Excellent resistance to stress corrosion cracking (SCC).
High-Temperature Performance: Stable mechanical properties up to 480°C.
Compatibility: Directly weldable to Monel 400 pipes/valves without special filler materials.
Material Specifications (UNS N04400 (Monel 400))
Composition: 67% nickel, 30% copper, with traces of iron and manganese.
Key Properties:
- Corrosion Resistance: Superior to stainless steel (e.g., 316L) in seawater, sulfuric acid, hydrofluoric acid (HF), and alkaline solutions.
- Temperature Range: -200°C to +480°C (long-term service).
- Strength: Tensile strength ≥550 MPa, hardness ≤200 HB.
Structure & Types
Three-Piece Design:
- Consists of two threaded or socket weld ends (male/female) and a central nut for quick assembly/disassembly.
- Sealing: Metal-to-metal contact (no gasket), relying on precision machining for leak-proof performance.
Connection Types:
- Threaded Unions: Use NPT threads for pipe connections.
- Socket Weld Unions: Welded to pipes for higher-pressure applications.
Pressure Ratings:
- Class 3000 (~750 psi) and Class 6000 (~1500 psi). Pressure-temperature ratings are defined in standard tables.
Typical Applications
- Offshore Engineering: Seawater pumps, marine piping systems.
- Chemical Industry: Sulfuric acid, hydrofluoric acid storage/transport equipment.
- Oil & Gas: Instrumentation lines in sour gas fields (H₂S/CO₂).
- Nuclear Industry: Cooling water systems in nuclear plants (radiation-resistant).
One-Stop MSS SP 83 B564 UNS N04400 Pipe Unions Provider for All Your Needs
SSM has significant product advantages in manufacturing MSS SP 83 B564 UNS N04400 Pipe Unions. Whether it’s quality or price, we will meet your needs.
More Information about MSS SP 83 B564 UNS N04400 Pipe Unions
MSS SP-83 Standard
Specifies the design, dimensions, and testing requirements for socket weld (SW) and threaded (NPT) unions, suitable for small-bore high-pressure piping (NPS 1/8″ to 4″).
Pressure ratings: Class 3000 (~750 psi) and Class 6000 (~1500 psi).
ASTM B564
Material standard for nickel alloy forgings, covering the chemical composition, mechanical properties, and manufacturing requirements of UNS N04400 (Monel 400).
Selection Guidelines
Welding Requirements:
- Use matching filler materials (e.g., ENiCu-7).
- Avoid excessive heat input to prevent intergranular corrosion.
Avoid:
- Oxidizing acids (e.g., concentrated nitric/sulfuric acid).
- Long-term use >480°C (reduced strength).
Maintenance:
- Regularly inspect threaded connections for vibration-induced loosening.
- Avoid chlorine-containing cleaners (risk of SCC).
Comparison with Other Materials
| Property | Monel 400 (UNS N04400) | 316L Stainless Steel | Hastelloy C-276 |
| Seawater Resistance | Excellent | Moderate (prone to pitting) | Excellent |
| HF Acid Resistance | Good (<70% concentration) | Not suitable (severe corrosion) | Excellent (all concentrations) |
| Cost | High (~3-5× 316L) | Low | Very high (~2× Monel) |
| Temp. Range | -200°C to +480°C | -50°C to +450°C | -200°C to +1093°C |
FAQ
Monel 400 (Ni-Cu alloy) excels in reducing acids (e.g., HF), while Inconel 625 (Ni-Cr-Mo alloy) offers better oxidation resistance and high-temperature performance.
Yes, but for >70% concentration or high temps (>50°C), consider Hastelloy B-3.
MSS SP-83 B564 UNS N04400 Pipe Unions are ideal for extreme corrosion (e.g., chlorides, acids) in offshore, chemical, and oil/gas applications.
Selection must balance media compatibility, temperature/pressure, and cost. Consult materials engineers for critical services.
For technical documents (e.g., dimensions, welding procedures), contact us!
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