654 SMO (UNS S32654 / Alloy 654) Forging Parts | China Leading ISO-Certified Manufacturer & Supplier

About Our 654 SMO (UNS S32654 / Alloy 654) Forging Solutions

Established in 1997, Jiangsu Liangyi Co., Limited is a professional ISO 9001:2015 certified manufacturer of high-performance 654 SMO (UNS S32654 / Alloy 654) forging parts in Jiangsu, China. Our 80,000㎡ factory has advanced forging equipment, including 2000–6000 ton hydraulic forging presses, 1–5 meter seamless rolling machines, and full in-house testing facilities, and we have an annual manufacturing capacity of 120,000 tons. We supply custom UNS S32654 forged parts from 30 KG to 30,000 KG to customers in over 50 countries across Europe, North America, the Middle East, Asia Pacific, and Africa. All of our products meet  ASTM, EN, and ASME standards.

As a top China-based Alloy 654 open die forging supplier, we provide a full range of service from steel melting, open die forging, seamless ring rolling, heat treatment, machining to non-destructive testing .All parts are made based on clients drawings and technical specifications. Explore our full range of forged products and forging materials. Our 654SMO seamless rolled rings and custom forgings are used for extreme corrosive, high-pressure, and high-temperature industrial environments.

654 SMO vs Competitive Alloys: Full Performance Comparison

CPT tested in 1M NaCl per ASTM G150; CCT tested in 6% FeCl₃ per ASTM G48 Method D. Values are representative for wrought/forged product forms. Contact our engineering team for application-specific corrosion data.

654 SMO Forged Bars & Rods

We supply UNS S32654 forged round bars, square bars, flat bars, rectangular bars, and step shafts with a maximum forging diameter up to 2 meters and weight up to 30 tons per piece. All forged bars are produced with a minimum 3:1 forging ratio, with full ultrasonic testing and EN 10204 3.1/3.2 mill test certificates. They are the best choice materials for valve stems, pump shafts, turbine components, and structural parts in corrosive environments.

654SMO Seamless Rolled Forged Rings

Our Alloy 654 seamless rolled forged rings are made with a maximum diameter up to 6 meters and single-piece weight up to 30 tons.These parts includ gear rings, valve body rings, flange blanks, bearing rings, and custom contoured rolled rings. Our 654SMO forged rings meet ASTM, ASME, and EN standards, and they are used for oil & gas wellhead equipment, pressure vessels, and industrial valves in the Middle East, Europe, and North America.

UNS S32654 Forged Housings, Sleeves & Hollow Components

We make custom 654 SMO forged hubs, housings, shells, sleeves, bushes, casings, and seamless hollow bars with an outer diameter capacity up to 3000 mm. These seamless hollow forgings can delete weld failure risks, so that they are the best choice material for heavy-wall cylinders, valve bodies, pump barrels, and pressure equipment in chemical processing, offshore oil & gas, and desalination applications.

Alloy 654 Forged Discs, Plates & Blocks

Our 654SMO forged discs, disks, plates, blocks, and flange blanks are produced with a strict minimum 3:1 forging ratio, making sure all parts have a fully wrought and consistent microstructure .. We supply custom sizes up to 3 meters in diameter and 20 tons in weight, they are used for tube sheets, baffle plates, pressure vessel closures, and structural parts for heat exchangers and reactors.

654 SMO Forged Valve & Oilfield Components

As a specialized China supplier of UNS S32654 forged valve parts, we make valve balls, bonnets, bodies, stems, closures, seat rings, cores, and discs for ball valves, check valves, gate valves, butterfly valves and back pressure valves.We supply forged wellhead components, Christmas trees, casing heads, tubing heads, casing hangers, tubing spools, drilling tools, risers, connectors and flanges for the oil and gas industry.

654SMO Forged Pressure Vessel & Heat Exchanger Components

We produce Alloy 654 forged pipes, tubes, shells, casings, barrels, reactor nozzles, channel flanges, tube sheets and baffle plates for boilers, heat exchangers, pressure vessels, reactors and industrial heaters. Our 654 SMO forgings fully meet ASME ,and they are used in European chemical plants, North American refineries, and other desalination projects around the world. They can work reliably for a long time even in high-temperature, high-chloride process media.

UNS S32654 Forged Turbomachinery & Pump Components

We make custom 654 SMO forged pump casings, impellers, shafts, housings, wear rings, centrifugal compressor impellers, turbine tie rods, and nuclear reactor coolant pump parts. Thanks to 654 SMO's high mechanical strength and excellent corrosion resistance, our forged parts improve equipment efficiency and lifetime for power generation, petrochemical, and nuclear power applications around the world.

Oil & Gas Upstream & Downstream Industry

654 SMO is the standard material for oilfield and offshore equipment exposed to high-chloride, high-sulfur (sour service) downhole environments. Our UNS S32654 oilfield forgings are the best choice material for onshore and offshore oil and gas projects in the Middle East, North Sea, Gulf of Mexico, and Southeast Asia.

Nuclear Power Generation Industry

Our Alloy 654 nuclear grade forgings have non-magnetic properties, excellent radiation resistance and great material purity , they are manufactured to meet international nuclear industry quality requirements. They are used for nuclear reactor coolant pump casings, impellers, seal chambers, rotors, and other critical safety-related parts in nuclear power plants across Asia and Europe.

Petrochemical & Chemical Processing Industry

Our UNS S32654 pressure vessel forgings are the best choice materials for heat exchangers, reactors, columns, and process equipment in chemical plants, refineries, and specialty chemical facilities. Our forgings meet ASTM and ASME standards and can be supplied with full EN 10204 3.1/3.2 mill test certificates.

Seawater Desalination & Marine Industry

Due to 654 SMO's excellent seawater corrosion resistance, it is the beset choice material for desalination equipment, marine offshore platforms, and shipboard systems. Our 654SMO forged valve parts and pressure parts are used in large-scale seawater desalination projects in the Middle East, Mediterranean, and Australia.

Turbomachinery & Industrial Pump Industry

Thanks to 654 SMO’s high mechanical strength, good ductility, and excellent formability, our Alloy 654 forged turbomachinery parts support lightweight, high-efficiency designs for centrifugal pumps, compressors, and turbines used in petrochemical, power generation, and oil and gas applications worldwide.

1. Premium Raw Material Melting Process

All our 654 SMO raw material is melted via two premium processes:

• EAF + AOD/VOD + Degassing: It is used for standard industrial applications, making sure all parts meet ASTM chemical composition requirements at optimized cost.
• EAF + AOD/VOD + Electroslag Remelting (ESR): It is used for nuclear grade, sour service, and important safety-related applications. ESR has ultra-high material purity, consistent microstructure, and near-zero inclusion content.

All raw material is fully tested for chemical composition (PMI + OES spectrometry) before entering the forging workshop, with full melt-to-finished-part traceability.

2. Precision Open Die Forging & Seamless Ring Rolling

Our 654 SMO forgings are produced on 2000–6000 ton hydraulic forging presses and 1–5 meter seamless ring rolling machines, with a strict minimum forging ratio of 3:1 (higher ratios applied for nuclear and critical safety applications). This provides a fully forged makeup across the entire component. eliminating internal porosity and segregation, and improving both mechanical properties and corrosion resistance. We support fully custom forging geometries based on your 2D/3D drawings.

3. Controlled Solution Heat Treatment

All UNS S32654 forged parts undergo precision solution annealing at 1150–1200°C, followed by rapid water quenching. This treatment:

• Fully dissolves chromium and molybdenum carbides and secondary phases (sigma, chi)
• Maximizes pitting and crevice corrosion resistance (restores full PREN 42.5)
• Provides a stable, fully austenitic microstructure throughout the forging part
• Meets the post-weld heat treatment requirement for important applications

We operate 10 computer-controlled heat treatment furnaces, supporting large-size forgings up to 15 meters in length and 30 tons in weight. Temperature uniformity is verified by calibrated thermocouples per AMS 2750 (Nadcap standard).

4. Precision CNC Machining & Finishing

Our in-house CNC machining workshop provides fine machining, surface treatment, and hardfacing services, delivering finished forgings ready for assembly:

• Dimensional Tolerances: It is up to IT6 for critical bore and shaft fits
• Surface Finish: It is Ra 0.8 µm for valve sealing surfaces; Ra 1.6–3.2 µm for general machined surfaces
• Hardfacing: Stellite® 6 / Stellite® 21 cobalt-based hardfacing alloy PTAW hardfacing for valve seat sealing surfaces (available upon request)
• Thread Machining: API, ASME, and custom thread profiles

5. Strict Non-Destructive Testing & Quality Inspection

We have advanced NDT, chemical composition testing, mechanical property testing, and metallographical testing equipment. All 654 SMO forgings undergo 100% ultrasonic testing (UT) per ASTM A388. Additional testing options include:

• Magnetic Particle Testing (MT) — ASTM E709
• Liquid Penetrant Testing (PT) — ASTM E165
• Radiographic Testing (RT) — ASTM E94
• Hardness Testing (HB / HRC / HV) — ASTM E10 / E18
• Charpy Impact Testing — ISO 148 (at -20°C, -40°C, or ambient)
• Intergranular Corrosion Testing — ASTM A262 Practice E
• Positive Material Identification (PMI) — XRF / OES
• ASTM G150 Critical Pitting Temperature (CPT) Test (available on request)
• ASTM G48 Method D Critical Crevice Corrosion Temperature (CCT) Test (available on request)

Applicable inspection standards: ASTM A370, A388/A388M, A262, A479/A479, A484/A484M; ISO 148.

Chemical Composition (ASTM Standard, Weight %)

PREN formula for 654 SMO: PREN = %Cr + 3.3×%Mo + 16×%N ≈ 24 + 3.3×7.3 + 16×0.5 = ~42.5

Mechanical Properties (Solution Annealed & Water Quenched)

Physical & Thermal Properties of 654 SMO (UNS S32654)

The following physical properties are essential for equipment design calculations, including heat exchanger thermal sizing, thermal stress analysis, and equipment weight estimation:

Critical Pitting Temperature (CPT) & Crevice Corrosion Temperature (CCT) Data

The Critical Pitting Temperature (CPT) and Critical Crevice Corrosion Temperature (CCT) are the most important parameters for evaluating an alloy's resistance to localized corrosion in chloride environments. Unlike the PREN formula (which is compositional), CPT and CCT are measured experimentally and directly reflect real-world performance in process media.

Global Compliance & Certification

• ISO 9001:2015 Quality Management System Certification
• ASTM / ASME Standard Compliance — ASTM A182 Grade F654, ASTM A388, ASTM A262, ASTM A370
• EN 10204 3.1 / 3.2 Mill Test Certificate Available
• Third-Party Inspection Supported (BV, SGS, TUV, DNV, etc.)

Recommended Welding Processes for 654 SMO

Filler Metal Recommendation for 654 SMO Welding

Always use matching 654 SMO filler metal for important corrosion-resistant applications. Common commercial filler metals include:

• Avesta P12 / Sandvik 27.31.4.LN: Matching 654 SMO GTAW/GMAW wire. Nominal composition: 27Cr-31Ni-4Mo-0.4N. Provides slightly overalloyed weld metal to compensate for dilution effects.
• Inconel 625 (ERNiCrMo-3): Alternative for dissimilar metal welds or when matching filler is unavailable. Good corrosion resistance but higher cost.

Key Welding Parameters & Controls

• Preheat: It is not needed for 654 SMO (unlike carbon steel). The material should be at ambient temperature before welding.
• Interpass Temperature: It needs to be strictly controlled below 150°C. Use contact thermometers or infrared pyrometers between passes. Excessive interpass temperature promotes sigma phase precipitation in the HAZ, reducing CPT by up to 30°C.
• Heat Input: Minimize heat input per pass (< 1.5 kJ/mm recommended for critical applications). Use stringer beads rather than weave beads.
• Shielding Gas: 100% Argon or Ar + 2–5% N₂ for GTAW. Nitrogen addition to shielding gas helps compensate for nitrogen loss during welding and maintains weld metal PREN.
• Back Purging: Always use 100% Argon back purging for root passes to prevent oxidation (sugaring) of the weld root, which significantly reduces corrosion resistance.
• Interpass Cleaning: Wire brush or grind between passes using stainless steel tools dedicated to 654 SMO (no carbon steel contamination).

Post-Weld Heat Treatment (PWHT) for 654 SMO

Unlike carbon steels, 654 SMO does NOT need stress-relief PWHT. However, for important corrosion-resistant applications (sour service, seawater, nuclear), post-weld solution annealing is strongly recommended:

• Temperature: 1150–1200°C (2100–2190°F)
• Hold Time: Minimum 30 minutes per 25mm of thickness; minimum 1 hour total
• Cooling: Rapid water quench (NOT air cool). Air cooling allows sigma and chi phase to precipitate in the 700–950°C range, which cannot be visually detected but causes severe embrittlement and loss of corrosion resistance.
• Verification: Post-PWHT corrosion testing per ASTM A262 Practice E (intergranular corrosion) and ASTM G150 (CPT verification) recommended for critical applications.

Jiangsu Liangyi has 10 computer-controlled heat treatment furnaces , which provides solution annealing of finished weld assemblies up to 15 meters in length as a post-fabrication service. Contact us for details.

Available Surface Treatments

The correct surface treatment is essential to make sure 654 SMO forgings get their full corrosion resistance potential. The forging surface must be free of scale, contamination, and embedded iron particles before service. Jiangsu Liangyi offers the following surface treatment options:

Export Packaging & Shipping Standards

All 654 SMO forging exports from Jiangsu Liangyi are packed to make sure all parts meet international shipping standards with zero corrosion and zero dimensional damage.

• Inner Packaging: Each forging is wrapped in VCI (Vapor Corrosion Inhibitor) polyethylene film, providing 24-month corrosion protection in sealed packaging. Desiccant silica gel packs are placed inside each sealed package.
• Outer Packaging: They are packaged in ISPM 15 certified solid wooden cases or wooden pallets ，meeting international phytosanitary standards for exports to the EU, US, Canada, Australia and other regions. Case interiors are lined with moisture-resistant protective paper.
• Marking: Each piece and outer case is marked with: material grade (654 SMO / UNS S32654), heat number, dimensions (OD × ID × L or weight), purchase order number, inspection stamp, and destination port per your requirements.
• Oversized Forgings: Forgings > 3 tons are shipped by open-top container, flat-rack container, or breakbulk, depending on dimensions. We coordinate oversized shipment logistics with our freight forwarding partners.
• Export Documentation: Full export documentation is provided with every shipment: commercial invoice, packing list, EN 10204 3.1/3.2 mill test certificate, certificate of origin, HS code classification, and customs clearance support.
• Insurance: All-risk marine cargo insurance available upon request. We work with Ping An Insurance and other internationally recognized cargo insurers.