Alloy 28，Incoloy 028 Fittings，UNS N08028,E FORU

British Specs:，American Specs:，German Specs:WS 1.4563

**Product Name:** Alloy 28 / Incoloy® 028 Fittings | UNS N08028 **Material Type:** Nickel-Iron-Chromium-Molybdenum Austenitic Stainless Steel Fittings **Standard:** ASTM B366, ASME SB366, MSS SP-43, ASME B16.9, ASME B16.11 --- ### **Overview** Alloy 28 Fittings (UNS N08028), commercially known as **Incoloy® 028**, are precision-engineered components manufactured from nickel-iron-chromium-molybdenum austenitic stainless steel, specifically designed for handling sulfuric acid and other aggressive chemical media. These fittings provide exceptional corrosion resistance and reliability in chemical processing, oil and gas, pollution control, and industrial piping systems where conventional stainless steels would fail. --- ### **Key Advantages** - **Superior Sulfuric Acid Resistance:** Excellent performance in sulfuric acid service across various concentrations and temperatures - **Outstanding Chloride Resistance:** Enhanced resistance to pitting, crevice corrosion, and stress corrosion cracking - **Excellent General Corrosion Resistance:** Suitable for wide range of corrosive media - **High Pressure Capability:** Robust design for demanding service conditions - **Easy Installation:** Standard dimensions for compatibility with existing systems - **Long Service Life:** Reduced maintenance and replacement costs --- ### **Chemical Composition (Typical Weight %)** | Element | Content (%) | Element | Content (%) | |---------|-------------|---------|-------------| | Nickel (Ni) | 29.0-32.0 | Chromium (Cr) | 26.0-28.0 | | Iron (Fe) | Balance | Molybdenum (Mo) | 3.0-4.0 | | Copper (Cu) | 0.6-1.4 | Manganese (Mn) | ≤2.0 | | Silicon (Si) | ≤1.0 | Carbon (C) | ≤0.03 | | Nitrogen (N) | 0.15-0.25 | Phosphorus (P) | ≤0.03 | | Sulfur (S) | ≤0.03 | | | --- ### **Physical & Mechanical Properties** #### **Physical Properties** - **Density:** 8.0 g/cm³ (0.289 lb/in³) - **Melting Range:** 1370-1400°C (2500-2550°F) - **Thermal Expansion Coefficient:** 15.5 × 10⁻⁶/°C (20-100°C) - **Modulus of Elasticity:** 200 GPa (29 × 10⁶ psi) - **Thermal Conductivity:** 12.0 W/m·K at 100°C - **Specific Heat Capacity:** 450 J/kg·K at 100°C #### **Mechanical Properties (Solution Annealed)** | Property | Typical Value | |----------|---------------| | Tensile Strength | 600-750 MPa (87-109 ksi) | | Yield Strength (0.2% Offset) | 300-400 MPa (44-58 ksi) | | Elongation | 35-50% | | Hardness | 170-220 HB | | Impact Strength (Charpy V) | ≥100 J (74 ft-lb) | --- ### **Product Specifications** #### **Available Fitting Types** - **Butt-Weld Fittings:** Elbows (45°, 90°, 180°), tees, reducers, caps, stub ends - **Socket-Weld Fittings:** Unions, elbows, tees, couplings, plugs - **Threaded Fittings:** NPT threads per ASME B1.20.1 - **Special Fittings:** Crosses, lap joint stub ends, nozzle fittings #### **Size Ranges** - **Butt-Weld:** 1/2" to 24" NPS (DN15 to DN600) - **Socket-Weld:** 1/8" to 4" NPS (DN6 to DN100) - **Threaded:** 1/8" to 2" NPS (DN6 to DN50) #### **Standards Compliance** - **ASME B16.9:** Factory-made wrought butt-welding fittings - **ASME B16.11:** Forged steel fittings, socket-welding and threaded - **MSS SP-43:** Wrought stainless steel butt-welding fittings - **ISO 4144:** Stainless steel fittings threaded ends --- ### **International Standards & Certifications** - **UNS:** N08028 - **ASTM/ASME:** B366/SB366 - **EN:** 10253-4 (Butt-welding pipe fittings) - **PED:** 2014/68/EU Category I/IV - **Certifications:** NACE MR0175, ISO 15156, ASME B31.3 --- ### **Applications** #### **Chemical Processing Industry** - Sulfuric acid production and handling systems - Phosphoric acid processing equipment - Chemical reactors and process vessels - Acid concentration systems - Process interconnecting piping - Heat exchanger connections #### **Oil & Gas Industry** - Downhole and surface equipment - Process piping in sour service - Heat exchangers in refining operations - Offshore platform piping systems - Wellhead components #### **Pollution Control** - Flue gas desulfurization (FGD) systems - Scrubbers and absorbers - Waste water treatment plant piping - Chemical waste processing systems #### **Pulp & Paper Industry** - Digester piping systems - Bleaching equipment piping - Chemical recovery systems #### **Industrial Applications** - Industrial chemical transfer systems - Heat exchanger piping connections - Process cooling systems - Industrial furnace components --- ### **Fabrication & Installation** #### **Welding Procedures** - **Preferred Methods:** GTAW (TIG), GMAW (MIG) - **Filler Metals:** Alloy 28, ERNiCrMo-4, ENiCrMo-4 - **Shielding Gas:** 100% Argon for GTAW - **Purge Gas:** Required for interior protection - **Heat Input Control:** Moderate to low recommended #### **Installation Guidelines** - **Alignment:** Proper alignment before welding - **Gap Control:** Maintain consistent root gap - **Cleaning:** Thorough cleaning before welding - **Support:** Adequate support during installation - **Inspection:** Visual and NDE as required #### **Quality Control** - **Visual Inspection:** 100% visual examination - **Dimensional Check:** Verify all critical dimensions - **Surface Finish:** Ensure proper surface condition - **Marking:** Clear identification per specifications - **Traceability:** Full material traceability maintained --- ### **Corrosion Resistance** #### **Chemical Resistance** - **Excellent:** Sulfuric acid (various concentrations and temperatures) - **Good:** Phosphoric acid, nitric acid, organic acids - **Resistant:** Chloride pitting and crevice corrosion - **Limited:** Hydrochloric acid, oxidizing chlorides #### **Special Features** - High chromium content provides excellent oxidation resistance - Molybdenum enhances resistance to localized corrosion - Copper addition improves resistance to sulfuric acid - Balanced composition for wide corrosion resistance --- ### **Quality Assurance** #### **Testing & Inspection** - Liquid penetrant testing - Hydrostatic testing - Dimensional verification - Material certification - Traceability documentation #### **Certification** - Mill test certificates to EN 10204 3.1/3.2 - Full material traceability - NACE MR0175/ISO 15156 compliance - PED certification for pressure applications --- ### **Pressure-Temperature Ratings** | Temperature (°C) | Maximum Allowable Pressure (bar) | |------------------|---------------------------------| | -29 to 38 | 52 | | 100 | 52 | | 150 | 48 | | 200 | 45 | | 250 | 42 | *Based on Schedule 40 fittings* --- ### **Conclusion** Alloy 28/Incoloy® 028 Fittings provide an exceptional combination of corrosion resistance, mechanical strength, and reliability for handling aggressive chemical media in piping systems. Their superior performance in sulfuric acid and chloride-containing environments, combined with strict adherence to international standards, makes them the preferred choice for critical applications in chemical processing, oil and gas, pollution control, and industrial sectors. The comprehensive quality assurance and certification ensure these fittings deliver long-term, trouble-free service in the most demanding corrosive applications. --- *Incoloy® is a registered trademark of Special Metals Corporation. All technical data are typical values and should be verified for specific applications. Consult manufacturer's specifications for project-specific requirements and applicable codes and standards.*

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 2698 gallon liquid totes Special package is available on request.