Is 1.4466 suitable for cryogenic service at −196°C?

Yes. 1.4466 is fully qualified for −196°C cryogenic service. As a fully austenitic steel with no ferrite, it has no ductile-to-brittle transition temperature. EN 10088-3 guarantees ≥60J transverse Charpy impact at −196°C. Production from Jiangsu Liangyi routinely achieves 80–130J transverse at −196°C, exceeding the minimum for LNG and cryogenic equipment standards.

What is the maximum ring size and forging weight available in 1.4466?

Jiangsu Liangyi produces 1.4466 seamless rolled rings up to 6,000 mm outer diameter and 30,000 kg (30 tons) per piece. Open die forgings (bars, discs, shafts) are available up to 30,000 kg single-piece weight, bars up to 2,000 mm diameter and 15,000 mm length, discs up to 3,000 mm diameter.

Do you provide EN10204 3.2 certification and third-party inspection for 1.4466 forgings?

Yes. EN10204 3.1 MTR is our standard delivery document. EN10204 3.2 certification — jointly issued by the customer's nominated third-party inspection body and our QC team — is available on request. Source inspection witness at forging, heat treatment, or testing stages can be facilitated through internationally recognized agencies including TUV Rheinland, Bureau Veritas, SGS, Lloyd's Register, DNV, Applus+, RINA, and others.

What is the ASTM equivalent of 1.4466 X1CrNiMoN25-22-2?

The closest ASTM UNS equivalent is UNS S31050, covering a similar high-Cr, high-Ni, ultra-low carbon, Mo-N urea-grade austenitic stainless steel composition. For ASME BPVC projects, the composition requirements are typically referenced directly from EN 10088-3. Our technical department can provide material equivalency documentation for ASME code projects.

1.4466 (X1CrNiMoN25-22-2) Forging Parts | China Urea Grade Stainless Steel Forging Manufacturer

Name: Jiangsu Liangyi Co., Limited
Address: Chengchang Industry Park, Jiangyin City, Jiangsu Province, 214400, CN
Telephone: +86-510-86107550
Price range: $$$

1.4466 X1CrNiMoN25-22-2 Urea Grade Stainless Steel Forged Parts — Seamless Rolled Rings, Round Bars and Custom Forgings manufactured by Jiangsu Liangyi Co., Limited, Jiangyin, China

About Jiangsu Liangyi & Our 1.4466 Forging Expertise

1997Established

25+Years Forging Experience

120,000TAnnual Capacity

50+Countries Served

80,000㎡Factory Area

Established in 1997 in Jiangyin City, Jiangsu Province — one of China's most strategically important heavy industry corridors along the Yangtze River — Jiangsu Liangyi Co., Limited has built over 25 years of specialized expertise in the open die forging and seamless rolled ring manufacturing of high-alloy stainless steels and nickel-base alloys. Our 80,000㎡ manufacturing facility houses a total original fixed asset investment exceeding 40 million USD, comprising a fully integrated production chain from vacuum degassing and steel melting through multi-stage forging, solution annealing heat treatment, precision CNC machining, and comprehensive in-house nondestructive testing — all under a single ISO 9001:2015 certified quality management roof.

Our engagement with 1.4466 (X1CrNiMoN25-22-2) urea-grade stainless steel began in the early 2000s, driven by growing demand from European and Middle Eastern urea fertilizer engineering contractors who required a China-based supplier capable of consistently meeting the stringent chemical composition control, ultra-low carbon guarantee, and full-process traceability demanded by this material. Over the following two decades, we have refined every aspect of the 1.4466 forging process — from melt chemistry optimization and forging temperature window control to solution annealing atmosphere management and IGC (intergranular corrosion) qualification testing — accumulating a depth of process knowledge that is simply not achievable without long-term, high-volume, hands-on manufacturing experience with this specific grade.

Today, our 1.4466 forgings are installed in operating urea synthesis reactors, offshore wellhead assemblies, nuclear power auxiliary systems, large-scale LNG terminals, and high-pressure heat exchangers across Europe, the Middle East, Southeast Asia, North America and Oceania. We produce single-piece forgings weighing from 30 kg to 30,000 kg, and seamless rolled rings up to 6 meters in outer diameter — a capability that positions us among a very small number of manufacturers globally able to supply the full size range demanded by major petrochemical and energy projects.

What Is 1.4466 (X1CrNiMoN25-22-2)? — A Complete Metallurgical Guide

1.4466, designated under the European EN 10088 standard as X1CrNiMoN25-22-2, is a fully austenitic, high-alloy stainless steel engineered specifically to overcome the most demanding corrosion challenge in the chemical process industry: the ammonium carbamate corrosion environment of urea synthesis. It is sometimes referenced under Swedish designation 2RE69 (Sandvik) and is recognized globally as the gold standard "urea grade" stainless steel — a material classification that only a handful of alloy grades have ever earned. Understanding why requires a close look at the metallurgy behind the designation.

The Urea Synthesis Corrosion Problem — Why Standard Stainless Steels Fail

Urea is synthesized from ammonia and carbon dioxide under high temperature (typically 180–185°C) and high pressure (typically 140–200 bar). The intermediate compound in this reaction — ammonium carbamate (NH₂COONH₄) — is one of the most corrosive substances encountered in industrial chemical processing. Its aggressive attack mechanism is uniquely damaging to standard austenitic stainless steels such as 316L: it preferentially attacks grain boundaries where chromium carbides have precipitated during processing or welding (a phenomenon called sensitization), causing catastrophic intergranular corrosion (IGC) that can reduce a component's service life from decades to months.

The industry's answer, developed and refined through decades of plant operating experience and material science research, is a steel with three simultaneous design targets: (1) an ultra-low carbon content that prevents carbide precipitation in the first place, (2) a dramatically elevated chromium content to build a robust, self-healing passive film, and (3) a carefully balanced addition of nitrogen to stabilize the austenitic phase and compensate for any remaining strength loss from the ultra-low carbon. 1.4466 / X1CrNiMoN25-22-2 is precisely the alloy system that achieves all three targets simultaneously.

The Role of Each Alloying Element in 1.4466 — Engineering the Perfect Balance

Why element balance matters in 1.4466: Unlike standard stainless steels where composition windows are broad, 1.4466 demands very tight control of each alloying element. Even small deviations — particularly in carbon, nitrogen, and the Cr/Ni ratio — can undermine the IGC resistance or destabilize the austenite phase. At Jiangsu Liangyi, we use full spectrometer analysis at every heat to confirm compliance before any forging begins.

1.4466 (X1CrNiMoN25-22-2) — Alloying Element Functions & Targets
Element	Target Range	Primary Metallurgical Function	Consequence of Deviation
Carbon (C)	≤ 0.020%	Ultra-low C is the defining feature of urea-grade stainless. Suppresses M₂₃C₆ carbide formation at grain boundaries, completely deleting intergranular sensitization risk even after welding or slow cooling.	C above 0.025% — even without visible sensitization — measurably reduces IGC resistance in ammonium carbamate. C above 0.030% disqualifies the material for urea service entirely.
Chromium (Cr)	24.0 – 26.0%	Forms the primary passive Cr₂O₃ oxide film. High Cr content (vs 16–18% in 316L) creates a dramatically thicker and more stable passive layer that is highly resistant to both oxidizing ammonium carbamate and pitting in chloride media.	Cr below 24% reduces passive film stability. Cr above 26% risks sigma phase formation during heat treatment, which embrittles the steel.
Nickel (Ni)	21.0 – 23.0%	Primary austenite stabilizer. The high Ni content (10-14% in 316L) compensates the high Cr and allows a fully stable austenitic microstructure without ferrite or martensite, which is essential for ductility, IGC resistance and low temperature performance.	Ni below 21% risks partial ferrite formation, which can become a preferential corrosion initiation site. Ni above 23% adds cost without performance benefit at this Cr/Mo level.
Molybdenum (Mo)	2.0 – 2.5%	Strongly improves pitting and crevice corrosion resistance by adsorbing into the passive film and increasing its resistance to chloride attack. Also improves resistance to reducing acid environments. Each 1% Mo raises the PREN (Pitting Resistance Equivalent Number) by approximately 3 points.	Mo below 2% leaves the material vulnerable to pitting in chloride-containing process streams that often co-exist in urea and oil/gas environments.
Nitrogen (N)	0.10 – 0.16%	The most important compensating element in 1.4466. Nitrogen is a powerful austenite stabilizer and solid-solution strengthener. It restores the yield strength lost from the ultra-low carbon, adds to pitting resistance (each 0.1% N raises PREN by approximately 16 points), and dramatically slows carbide precipitation kinetics, further protecting grain boundaries.	N below 0.10% weakens the steel mechanically and reduces PREN. N above 0.16% risks nitrogen porosity in welds and can complicate forging if not properly controlled during melting.
Manganese (Mn)	≤ 2.0%	Secondary austenite stabilizer, substituting for some nickel. Also improves hot ductility and deoxidizes the melt. However, excess Mn can form MnS inclusions that serve as pitting initiation sites, so it is kept intentionally low.	Mn above 2% significantly increases MnS inclusion density, reducing corrosion resistance and fatigue life.
Silicon (Si)	≤ 0.70%	Deoxidizer during melting. Provides some resistance to high-temperature oxidation. In some urea-grade interpretations, low Si (<0.5%) is preferred as Si can promote sigma phase formation at high Cr levels during certain heat treatment cycles.	Si above 0.70% accelerates sigma phase precipitation at the solution annealing boundary temperatures, compromising toughness.
Phosphorus (P)	≤ 0.025%	Residual impurity kept strictly low. P segregates to grain boundaries and sharply reduces IGC resistance — exactly the opposite of what 1.4466 is designed for. Stringent P control is a quality hallmark of genuine urea-grade material.	P above 0.025% measurably increases IGC attack rate in ammonium carbamate testing (Huey test). Some specifications require P ≤ 0.020% for important urea plant applications.
Sulfur (S)	≤ 0.010%	Residual impurity minimized to reduce MnS inclusion density. Each MnS inclusion is a potential pitting initiation site in chloride or acidic media. Low S also improves hot workability during forging, which is important for large cross-section billets.	S above 0.010% increases pitting susceptibility and can cause hot-shortness cracking during heavy forging operations on large cross-sections.

PREN — Quantifying 1.4466's Corrosion Superiority

Pitting resistance equivalent number (PREN) is an empirically derived index, which is used to indicate the pitting resistance of stainless steels: PREN = %Cr + 3.3×%Mo + 16×%N. Higher PREN indicates better pitting resistance. Using typical mid-range compositions, 1.4466 achieves a PREN of approximately 38–40, versus 24–26 for standard 316L and 30–32 for 316L + higher Mo variants. This PREN advantage translates directly to a dramatically expanded range of operating environments where 1.4466 remains passive and corrosion-free — including many conditions that would cause rapid localized corrosion of lower-PREN stainless steels.

💡 Key Insight from Our Manufacturing Experience: Over 25+ years of producing 1.4466 forgings, we have observed that the material's performance is sensitive to the Cr/Ni ratio and N content, not just minimum values. Based on our production records, heats with Cr near 25.5% and N near 0.14% — both well within specification — tend to show better IGC test results than heats at 24.2% Cr and 0.11% N. We deliberately target the upper half of each specification range and document the achieved composition on every EN10204 3.1 certificate we issue.

1.4466 vs Other Stainless Grades — Full Comparison & Selection Guide

Engineers specifying materials for urea, oil & gas, chemical processing and cryogenic applications often need to evaluate 1.4466 against alternative grades. The following table provides a direct, technically grounded comparison based on our manufacturing experience and published corrosion data — helping you understand precisely where 1.4466 excels and where alternative grades may be considered:

Comparison: 1.4466 vs Common Alternative Stainless Steel Grades
Property / Criteria	1.4466 (X1CrNiMoN25-22-2)	316L (1.4404)	904L (1.4539)	310S (1.4845)	Duplex 2205 (1.4462)
Cr Content	24–26%	16–18.5%	19–23%	24–26%	22–23%
Ni Content	21–23%	10–14%	23–28%	19–22%	4.5–6.5%
Mo Content	2.0–2.5%	2.0–2.5%	4.0–5.0%	None	3.0–3.5%
Carbon Content (max)	≤ 0.020%	≤ 0.030%	≤ 0.020%	≤ 0.080%	≤ 0.030%
Nitrogen Addition	0.10–0.16%	None / trace	None / trace	None	0.10–0.22%
PREN (approx.)	38–40	24–26	34–37	~24	34–38
IGC Resistance (Ammonium Carbamate)	Excellent — designed for this	Poor — rapid failure	Moderate	Poor	Moderate
Cryogenic Toughness (−196°C)	Excellent (≥60J)	Good	Excellent	Good	Not recommended — brittle at cryogenic temps
Stress Corrosion Cracking Resistance	Very Good	Poor in hot Cl⁻	Good	Poor	Excellent
High-Temp Oxidation Resistance (>800°C)	Moderate	Limited	Limited	Excellent	Moderate
Forgeability (Large Cross-Section)	Excellent (fully austenitic — uniform deformation)	Excellent	Good	Good	Moderate (dual-phase requires precise temp control)
Urea Plant Approval	Global industry standard	Not approved	Not standard	Not approved	Not approved

⚠ Critical Warning for Material Substitution: We regularly receive inquiries from procurement teams asking whether 316L or 904L can substitute for 1.4466 in urea plant applications to reduce cost. The answer is categorically no. The ammonium carbamate corrosion mechanism specifically attacks the grain boundary structure of austenitic steels with C above approximately 0.020%, causing IGC failures that are rapid, unpredictable, and potentially catastrophic. No cost saving from using a lower-grade material justifies this risk. If you have any doubt about the correct material specification for your application, our technical team is available to review your process parameters and provide a documented material selection recommendation.

Core Performance Advantages of 1.4466 (X1CrNiMoN25-22-2) Forged Steel

✓ Zero Intergranular Sensitization Risk

With carbon ≤0.020% achieved through AOD or VOD refining, M₂₃C₆ carbide precipitation at grain boundaries is thermodynamically suppressed even after slow cooling or multi-pass welding heat cycles. This is not a compromise — it is absolute protection against the single most common failure mechanism in urea plant stainless steel components.

✓ Superior Passive Film Stability

The combination of 24–26% Cr and 2.0–2.5% Mo creates a passive oxide film that is both thicker and more chemically stable than that of standard grades. Published corrosion literature and industry experience indicate that properly manufactured 1.4466 achieves substantially lower corrosion rates than 316L in ammonium carbamate testing (Huey test per ASTM A262) — a well-documented performance advantage that is the primary reason for its global adoption in urea synthesis applications.

✓ Nitrogen-Boosted Mechanical Strength

The 0.10–0.16% N addition is not merely a bonus — it is an engineered compensator that raises yield strength to ≥250–260 MPa despite the ultra-low carbon, while simultaneously improving fatigue resistance and delaying austenite decomposition during service. Components designed to thinner walls without sacrificing pressure rating are achievable, delivering direct weight and cost savings on large pressure vessel assemblies.

✓ Exceptional Cryogenic Toughness

Fully austenitic microstructure with no delta-ferrite means no ductile-to-brittle transition temperature down to liquid nitrogen temperatures. At −196°C, 1.4466 maintains ≥60 J transverse Charpy impact energy — meeting the most demanding cryogenic equipment standards without special heat treatment modifications.

✓ Broad Corrosive Media Compatibility

Apart from urea synthesis, PREN 38–40 of 1.4466 also exhibits reliable passive behavior in hot concentrated phosphoric acid, formic acid, acetic acid, chloride solutions at elevated temperatures, and mixed oxidizing/reducing acid environments — expanding the material’s application in chemical, pharmaceutical, and desalination industries.

✓ Excellent Forging Characteristics

As a single-phase fully austenitic alloy, 1.4466 deforms uniformly during hot forging with predictable metal flow and no phase transformation complications. Compared to duplex stainless steels, which require extremely tight temperature control to maintain the correct phase balance, 1.4466 is more forgiving across the forging temperature window, enabling superior dimensional accuracy on complex large forgings.

Our 1.4466 Forging Manufacturing Process — From Melt to Certified Part

The quality of a 1.4466 forged component is determined not just by its final chemical composition, but by every step from the initial melt chemistry through the final heat treatment and dimensional inspection. At Jiangsu Liangyi, we control the entire production chain in-house, so that we can take responsibility for quality at every stage rather than relying on sub-suppliers. Below is a transparent overview of our integrated manufacturing process for 1.4466 forgings:

Raw Material & Melt Chemistry Control

AOD/VOD refining guarantees C ≤0.020% and N 0.10–0.16%. Full spectrometer PMI performed on every heat before casting.

Ingot & Billet Casting

Parameters of controlled solidification minimize segregation.Each ingot is assigned a unique heat number that can be traced through all subsequent production

Heating & Temperature Control

Billets are heated to the forging temperature window (typically 1050–1200°C for 1.4466) in precisely controlled gas-fired or electric furnaces with pyrometer monitoring.

Open Die Forging / Ring Rolling

Multi-directional forging breaks down as-cast dendritic structure and achieves consistent fine-grain microstructure throughout the cross-section. Ring rolling controlled by CNC ring rolling mill.

Solution Annealing Heat Treatment

All 1.4466 forgings are solution annealed at 1050–1100°C followed by rapid quenching (water or forced air) to fully dissolve carbides and restore maximum corrosion resistance.

Dimensional & Surface Inspection

CMM 3D coordinate measurement, optical instruments and manual inspection to customer drawing tolerances before any destructive or NDT sampling.

Full NDT Inspection

UT (Ultrasonic Testing), PT (Dye Penetrant Testing), MT (Magnetic Particle Testing), RT (Radiographic Testing) per applicable EN / ASTM / API standards.

Mechanical & Chemical Testing

Tensile, yield, elongation, Charpy impact, hardness — all tested in our in-house laboratory equipped with calibrated instruments. Chemical composition confirmed by OES spectrometer.

IGC / Corrosion Testing (if specified)

Huey test (ASTM A262 Practice C) or Strauss test (ASTM A262 Practice E) for IGC qualification. Pitting resistance testing available per ASTM G48.

Documentation & Certification

EN10204 3.1 or 3.2 MTR issued with full traceability. Third-party inspection (TUV, BV, SGS, LR, DNV) facilitated on request.

Solution Annealing — The Most Critical Step for 1.4466 Corrosion Performance

Of all the manufacturing steps, solution annealing heat treatment is arguably the most consequential for the final corrosion resistance of a 1.4466 forging. The objective is to heat the forging to a temperature high enough (1050–1100°C) to fully dissolve any carbides or intermetallic phases that may have formed during forging or slow cooling, and then quench it rapidly enough to "freeze" the alloy in the fully solutionized, single-phase austenitic state before these phases can re-precipitate.

The quench rate is critical: too slow, even by just a few degrees per minute through the sensitization temperature range (approximately 500–800°C), can allow sufficient carbide precipitation to degrade IGC resistance — even from the ultra-low 0.020% carbon level. In our facility, large section forgings (above 300 mm cross-section) are water quenched directly from the furnace with precisely controlled water flow rates to ensure the cooling rate through the sensitization range consistently exceeds our internal minimum. Thinner sections may qualify for forced air quenching where validated by production testing. Every heat treatment furnace cycle is chart-recorded and the time-temperature profile is included as part of the delivery documentation for any customer who requests it.

Forging Temperature Window — Maintaining Austenitic Phase Stability

1.4466 is a fully austenitic steel at all normal forging temperatures, which in principle makes it easier to forge than duplex grades. However, the material does present its own specific forging challenges. At temperatures above approximately 1200°C, the grain growth rate accelerates significantly, and forging at excessively high temperatures can produce coarse-grained microstructures that, while meeting specification minimums, are suboptimal for fatigue performance in rotating equipment applications. Conversely, forging below approximately 1000°C significantly increases forging forces and risks strain localization, particularly in large cross-section billets.

Our production engineers use thermocouple verified furnace charts, infrared surface temperature monitoring on the forging press and established reheat schedules to keep the work-piece temperature in the optimal range through the entire forging sequence. For complicate multi-step forgings such as large flanged shafts or stepped rings, multiple reheat cycles are scheduled into the forging schedule rather than risk cold-working from excessive temperature drop.

Complete Range of 1.4466 / X1CrNiMoN25-22-2 Custom Forged Products

Jiangsu Liangyi manufactures 1.4466 forgings across the full dimensional spectrum demanded by global industrial projects — from precision-machined 30 kg pump shafts to 30-ton reactor nozzle forgings and 6-meter diameter seamless rings for large pressure vessel assemblies. Every product is manufactured from independently verified heat-compliant 1.4466 material and supplied with full production traceability. Explore our complete product range:

1. Forged Bars, Shafts & Spindles

We produce X1CrNiMoN25-22-2 forged round bars, square bars, flat bars, rectangular bars, step shafts, splined drive shafts, valve spindles, and solid blanks in diameters from 50 mm up to 2,000 mm and lengths up to 15,000 mm. All forged bars undergo 100% ultrasonic testing per EN 10308 or equivalent ASTM A388, with UT indication acceptance to EN / ASTM Class 3 or better. The forging process produces a wrought fiber structure that significantly improves the mechanical properties — particularly toughness and fatigue strength — compared to centrifugal casting or machining from plate. This is especially important for rotating components such as pump shafts, compressor shafts, and valve spindles where dynamic loading cycles during service demand the highest possible material integrity.

Our most commonly supplied bar/shaft geometries in 1.4466 include: stepped pump shafts with multiple diameter transitions, splined drive shafts for mud motor applications in downhole drilling, venturi meter body blanks for precision-machined flow measurement devices, and ultrasonic flowmeter spool body blanks. We routinely machine these to finished dimensions in our CNC workshop and supply them ready for assembly in customer equipment.

2. Seamless Rolled Forged Rings

Our seamless rolled ring capability in 1.4466 covers outer diameters from 200 mm to 6,000 mm, with wall thicknesses from 20 mm to 600 mm and heights from 50 mm to 1,500 mm — making us one of the few manufacturers globally capable of supplying the very largest ring sizes demanded by major refinery and fertilizer plant construction projects. All rings are produced by the seamless ring rolling method, which creates a continuous circumferential grain flow pattern (known as hoop direction grain flow) that provides superior mechanical properties in the radial and tangential directions — the critical loading directions for pressure-containing ring components.

We produce 1.4466 seamless rings in rectangular, contoured (flanged), and profiled cross-sections including T-section rings, L-section flanges, and custom profiled rings that minimize machining stock and reduce final component weight. Typical ring products include: gear rings and bearing rings for rotating machinery, large flange blanks for pressure vessel nozzles and manways, valve seat ring blanks for high-pressure ball valves and gate valves, ring-type closure heads for high-pressure reactor vessels, and circumferential joint rings for large diameter pipeline connectors.

3. Forged Sleeves, Hollow Bars & Heavy-Wall Cylinders

1.4466 forged sleeves, hollow bars, thick-wall cylinders, casing shells, and tubular housings are produced with outer diameters up to 3,000 mm and bore diameters from 100 mm upward, in lengths up to 5,000 mm. These hollow forgings are preferred over machining from solid bar for large bore applications because: (1) the hollow forging process removes the segregated central zone of the original ingot, which is the lowest-quality material zone; (2) the forging process produces radial grain flow in the remaining wall material, significantly improving mechanical properties in the hoop and axial directions; (3) material waste from bore machining is dramatically reduced, lowering final component cost despite the higher forging complexity.

Common applications include high-pressure heat exchanger shells, reaction vessel pressure-containing shells, downhole drilling tool housing cylinders, sleeve valves and plug valve bodies, and large bore pump barrel forgings. We supply these both as rough-forged blanks and as CNC-finished components with precision-ground bores, machined threads, and specified surface finishes.

4. Forged Discs, Tube Sheets, Baffle Plates & Flanges

Our disc and plate forging capability covers diameters up to 3,000 mm and thicknesses from 30 mm to 800 mm, in weights up to 15,000 kg as single-piece forgings. Tube sheets are among our most precision-demanding products: these large-diameter discs must be forged to very tight thickness tolerances (typically ±3–5 mm on a 300 mm nominal thickness) and then precision-machined to drilling-ready finish, with thousands of tube holes drilled to precise pitch and perpendicularity tolerances. A single tube sheet failure in a heat exchanger due to material defects or poor corrosion resistance is an extremely costly event requiring complete exchanger disassembly. Our 100% UT inspection of tube sheet forgings before machining ensures no internal defects are present that would be revealed only after expensive machining work is complete.

Our flange range in 1.4466 covers standard weld neck, slip-on, blind, socket weld, lap joint, and custom-profiled flanges from DN15 to DN2000 and ANSI Class 150 through Class 2500. For special applications such as double studded adapter flanges (DSAs) used in subsea wellhead and Christmas tree applications, we produce forged billets machined to the precise API 6A dimensional requirements, with chemical, mechanical and NDT testing documentation as specified by our customers' API 6A licensed manufacturers.

5. Custom Valve Forgings

We supply the complete set of forgings required for high-pressure and cryogenic valves in 1.4466, including: valve bodies for ball valves (forged split-body, trunnion-mounted, floating ball), gate valves, globe valves, and check valves; valve bonnets; valve balls and stems; valve seat ring blanks; valve body closure flanges; and yoke forgings for gate and globe valve actuation systems. For cryogenic butterfly valves — a demanding application where the combination of low temperature, high-purity process media, and precise flow control requires exceptional material quality — we supply the body, disc, and shaft forgings with material qualifications including impact testing at −196°C and EN10204 3.1 MTR as standard; EN10204 3.2 certification (jointly issued with customer-nominated third-party) is available on request.

6. Pump & Compressor Component Forgings

For the turbomachinery and fluid handling industry, we manufacture precision-forged 1.4466 pump casings, impellers, pump barrel housings, pump shafts, wear rings, diffuser rings, and centrifugal compressor impeller blanks. Pump and compressor components in 1.4466 are particularly valued in urea service (where process pumps circulate highly corrosive ammonium carbamate solutions) and in high-purity chemical and pharmaceutical applications where material integrity and surface finish are critical. Our CNC machining capability allows us to supply these complex geometries to finished dimensions, reducing our customers' lead time and downstream machining cost.

Industry Applications & Global Project Cases — 1.4466 Forgings in Service

Our 1.4466 forgings have been placed into service in some of the world's most demanding industrial environments. The following section describes each major application domain in depth, with specific component examples and the engineering rationale for material selection. View more project references on our official website.

Urea Production & Fertilizer Manufacturing — The Primary Application Domain

Urea (CO(NH₂)₂) is the world's most widely consumed nitrogen fertilizer and an essential industrial chemical. Global urea production exceeds 180 million metric tons per year, with the vast majority produced via the Stamicarbon or Snamprogetti (Saipem) high-pressure synthesis process. Every major urea plant contains critical pressure-containing and fluid-handling equipment that must resist the combined attack of ammonium carbamate at temperatures up to 185°C and pressures up to 200 bar — one of the harshest process environments in the entire chemical industry.

The global industry has converged on 1.4466 (X1CrNiMoN25-22-2) as essentially the only acceptable material for the highest-risk components in these systems, after decades of field experience demonstrated the inadequacy of 316L, 316Ti, and other previously specified grades. Components that Jiangsu Liangyi regularly supplies for urea plant construction and maintenance include: high-pressure urea synthesis reactor nozzle forgings, high-pressure stripper tube sheet and baffle plate forgings, high-pressure carbamate condenser tube sheet forgings, HP scrubber component forgings, urea solution pump casings and impellers, high-pressure valve body and bonnet forgings for the reactor feed and product isolation valves, and channel flange forgings for all high-pressure heat exchanger sections.

We have supplied custom 1.4466 forging packages for urea plant projects in the Netherlands, Germany, Saudi Arabia, Kuwait, UAE, Qatar, India, Malaysia, Indonesia, Thailand, and Australia — working directly with major EPC contractors and proprietary process licensors. Our extensive experience with the specific drawing and documentation requirements of urea plant projects means we can process customer purchase orders efficiently and meet the detailed inspection witness and documentation requirements that these projects demand.

Oil & Gas — Onshore Wellheads, Offshore Platforms & Subsea Systems

The oil and gas industry presents a combination of corrosion challenges — H₂S-induced sulfide stress cracking (SSC), CO₂-induced sweet corrosion, chloride pitting in formation brine, and crevice corrosion in tight clearance assemblies — that makes material selection both critically important and technically complex. For sour service applications (H₂S partial pressure above NACE threshold), 1.4466 offers exceptional SSC resistance by virtue of its fully austenitic microstructure (austenite is inherently more resistant to hydrogen embrittlement than martensitic or ferritic structures) and the high nitrogen content that further suppresses hydrogen absorption.

We supply X1CrNiMoN25-22-2 forgings produced to the dimensional and material requirements referenced in API 6A, for incorporation into API 6A licensed equipment. Typical components include: wellhead Christmas tree body forgings (gate valves, check valves, choke body forgings), blowout preventer (BOP) ram forgings and body component forgings, casing head and tubing head spool forgings, tubing hanger and casing hanger body forgings, subsea connector and riser component forgings, drill collar blanks and downhole tool housing forgings, and mud motor splined drive shaft forgings for directional drilling tools. For offshore applications in environments such as the North Sea, Persian Gulf, and Southeast Asian deepwater fields, the combination of 1.4466's pitting resistance and excellent mechanical properties makes it a reliable long-term choice where component replacement is prohibitively expensive.

Nuclear Power Generation — Safety-Critical Component Supply

Nuclear power plants impose the most demanding quality requirements of any industry — a consequence of the safety-critical nature of the components involved and the extremely long design service lives (40–60+ years) required. The use of 1.4466 in nuclear applications exploits the material's unique combination of very high corrosion resistance in reactor coolant chemistry, excellent low-temperature impact toughness (relevant for emergency cooling scenarios), absence of delta-ferrite (ferrite can become embrittled under neutron irradiation through alpha prime precipitation), and stable mechanical properties under prolonged thermal exposure.

Jiangsu Liangyi has supplied 1.4466 / X1CrNiMoN25-22-2 forgings for nuclear power auxiliary system components including: primary coolant pump housing components, pressure vessel nozzle forgings for auxiliary cooling systems, containment vessel penetration seal assembly forgings, emergency core cooling system (ECCS) valve and pump forgings, and reactor building ventilation duct flange forgings. All nuclear supply is performed under our ISO 9001:2015 quality management system with additional nuclear quality supplemental requirements as specified by the customer, and with full third-party source inspection (typically by customer-designated third-party Q.A. representatives or internationally recognized inspection agencies).

Chemical Processing — Pressure Vessels, Heat Exchangers & Reactors

Beyond urea synthesis, 1.4466 finds widespread application across the broader chemical processing industry wherever standard stainless steels are inadequate due to the combination of high corrosivity, elevated temperature, and pressure. Specific chemical process environments where 1.4466 is specified include: concentrated hot phosphoric acid processing (fertilizer and electronics industries), formic acid and acetic acid production and handling, pharmaceutical API synthesis where contamination prevention and material purity are paramount, desalination high-pressure membrane housing and pump components, fine chemicals production involving halogenated solvents, and chlor-alkali plant wet chlorine gas handling equipment.

For these applications, we manufacture 1.4466 forged pressure vessel shell sections, tube sheet pairs (fixed and floating), baffle plates with precise tube hole drilling, channel flanges and closure heads, nozzle forgings of all sizes and pressure classes, vessel support forgings, and heat exchanger header forgings. Our experience with ASME Boiler & Pressure Vessel Code Section VIII requirements (in addition to EN 13445 for European projects) allows us to supply these components with the specific documentation, material test reports, and dimensional certifications required for code-stamped pressure vessel construction.

Turbomachinery, Cryogenic & LNG Applications

The global transition toward cleaner energy has driven significant growth in LNG liquefaction and regasification infrastructure, creating sustained demand for cryogenic-grade materials that can reliably perform at liquid nitrogen and liquid natural gas temperatures (−160°C to −196°C) over decades of service. 1.4466 is uniquely positioned for these applications: its fully austenitic structure eliminates the ductile-to-brittle transition that limits ferritic and martensitic steels at low temperatures, while its high alloy content provides superior corrosion resistance in the marine and coastal environments where LNG terminals are typically sited.

We supply 1.4466 cryogenic forgings for: LNG pump casing and impeller forgings for submerged LNG pump assemblies, cryogenic high-performance butterfly valve disc and body forgings, cryogenic centrifugal compressor impeller blanks, cold box piping component forgings, LNG storage tank penetration seal forgings, nitrogen liquefier and vaporizer component forgings, and cryogenic flow control valve body forgings. All cryogenic-service 1.4466 forgings are tested with Charpy V-notch impact testing at the actual specified service temperature (−196°C or as specified), not merely at a representative sub-zero temperature, to provide direct evidence of adequate toughness at the actual operating condition.

Other Demanding Applications

The unique property profile of 1.4466 — ultra-low carbon, high PREN, excellent low-temperature toughness, full austenitic stability — makes it the material of choice for numerous other industrial applications that don't fall neatly into the categories above. These include: electrical submersible pump (ESP) motor housing forgings for high-GOR and sour oil wells, venturi cone flow meter body forgings for custody transfer measurement in corrosive fluids, marine riser and subsea pipeline connector forgings for deepwater applications, specialized desalination high-pressure pump component forgings, and custom industrial machinery components in pharmaceutical, food processing, and semiconductor manufacturing equipment where contamination-free performance and long maintenance intervals are critical.

Chemical Composition of 1.4466 (X1CrNiMoN25-22-2) — Standard & Our Typical Achieved Values

The following table shows both the EN 10088-3 specification limits and our typical achieved composition range for production heats, reflecting our deliberate targeting of the upper-performance portion of each specification window:

1.4466 Chemical Composition — EN 10088-3 Specification vs Jiangsu Liangyi Typical Achieved Values
Element	EN 10088-3 Min	EN 10088-3 Max	JL Typical Achieved	Role Summary
Iron (Fe)	Balance	Balance	Balance	Matrix element
Chromium (Cr)	24.00%	26.00%	25.0–25.8%	Passive film, pitting resistance
Nickel (Ni)	21.00%	23.00%	21.5–22.5%	Austenite stabilizer, IGC resistance
Molybdenum (Mo)	2.00%	2.50%	2.10–2.40%	Pitting / crevice resistance (PREN boost)
Nitrogen (N)	0.10%	0.16%	0.12–0.15%	Strength compensation, carbide suppression, PREN boost
Carbon (C)	—	0.020%	≤ 0.015%	Must be ultra-low — sensitization prevention
Manganese (Mn)	—	2.00%	≤ 1.50%	Austenite stabilizer, hot ductility
Silicon (Si)	—	0.70%	≤ 0.50%	Deoxidizer — minimize sigma risk
Phosphorus (P)	—	0.025%	≤ 0.020%	Impurity — strict control for IGC performance
Sulfur (S)	—	0.010%	≤ 0.005%	Impurity — minimize for pitting and hot workability

Note on Carbon Control: While EN 10088-3 permits C up to 0.020%, our production routinely achieves ≤0.015% — a meaningful margin below the limit. In our experience and based on published corrosion literature, every reduction in carbon below 0.020% provides an incremental further improvement in IGC resistance. We consider this tighter carbon control a cost-free quality enhancement that adds direct value to our customers' applications.

Mechanical Properties of 1.4466 Forged Steel — Specification, Context & Significance

All 1.4466 forgings from Jiangsu Liangyi are delivered in the solution-annealed condition (+A) or as-annealed with thermomechanical processing (+AT), with guaranteed mechanical properties fully compliant with EN 10088-3. The following table provides the specification values along with engineering context to help designers understand the significance of each property:

1.4466 Mechanical Properties — EN 10088-3 Guaranteed Values with Engineering Context
Property	Condition	Guaranteed Value	Engineering Significance
Tensile Strength (Rm)	+A / +AT	540 – 740 MPa	The upper limit serves as a cap: excessively high strength in austenitic steels can be associated with incomplete solution annealing or cold work. The 540 MPa minimum guanrantees adequate load-bearing capacity for pressure-retaining components.
0.2% Proof Strength (Rp0.2)	+A (annealed)	≥ 250 MPa	This is the yield-equivalent value used for pressure vessel wall thickness design calculations per ASME VIII or EN 13445. Higher than typical 316L (+A) minimum of ~220 MPa, thanks to nitrogen solid solution strengthening — enabling thinner walls for equivalent pressure rating.
0.2% Proof Strength (Rp0.2)	+AT (thermomechanical)	≥ 260 MPa	The +AT condition — involving controlled thermomechanical processing — provides an additional 10 MPa yield strength increase without compromising corrosion resistance, useful for applications requiring maximum design efficiency.
Elongation at Fracture (A)	Longitudinal (+AT)	≥ 40%	Exceptional ductility in the forging direction. This high elongation value ensures that components will deform plastically and give visible warning before fracture, critical for pressure safety.
Elongation at Fracture (A)	Transverse (+AT)	≥ 30%	Transverse (short-transverse) ductility of ≥30% confirms isotropic behavior and absence of deleterious banding or segregation in the forging cross-section. We routinely achieve 35–45% transverse elongation in production testing.
Charpy Impact Energy (KV) Longitudinal	+A at +20°C	≥ 100 J	Excellent room-temperature impact toughness — more than adequate for all standard industrial applications. Fully austenitic structure ensures no concern about ductile-to-brittle transition.
Charpy Impact Energy (KV) Transverse	+A at +20°C / −196°C	≥ 60 J	The −196°C specification is the cryogenic qualification criterion. ≥60 J at liquid nitrogen temperature is the threshold for LNG equipment standards. Our production consistently achieves 80–120 J transverse at −196°C, well above the minimum.
Brinell Hardness (HB)	+A	≤ 240 HB	The hardness maximum limits ensure the material is in the fully annealed condition and has not been work-hardened or incompletely heat treated. Values above 240 HB would indicate cold work or incomplete solution annealing, both of which compromise corrosion resistance.

High-Temperature Mechanical Properties — Design Considerations for Elevated Service

For applications where 1.4466 components operate at elevated temperatures — such as urea synthesis reactor internals (operating at up to 185°C) — designers must account for the reduction in 0.2% proof strength with increasing temperature. As a general reference based on published EN material data, 1.4466 proof strength at 100°C is approximately 90% of room-temperature values, at 150°C approximately 83%, and at 200°C approximately 78%. These are indicative figures only — for design purposes, always reference the applicable EN or ASTM material standard or consult our technical department, as values vary between heats based on the exact N content achieved.

Welding & Fabrication Guidance for 1.4466 (X1CrNiMoN25-22-2) Forgings

One of the most important practical questions customers ask us as forging suppliers is: "How does 1.4466 weld, and what do we need to know to maintain corrosion performance in the weld zone?" This is a legitimate and critically important question for any application where the forging will be welded into a larger assembly. The good news is that 1.4466 is well-suited to welding — but there are specific practices that must be followed to preserve its exceptional corrosion resistance through the weld zone.

Why Ultra-Low Carbon Is the Key to Weld Zone IGC Performance

The primary reason 1.4466 maintains good IGC resistance in the heat-affected zone (HAZ) of welds is its ultra-low carbon content. In standard 304 or 316 stainless steels, the HAZ is the most vulnerable zone: the heat cycle from welding causes carbon to diffuse to grain boundaries and form M₂₃C₆ chromium carbides, locally depleting the chromium concentration at grain boundaries below the ~12% threshold needed to maintain passivity. This is sensitization, and it can occur in the HAZ within seconds during welding. In 1.4466 with C ≤0.020%, there is simply insufficient carbon available to form damaging carbide concentrations, even in the slow-cooled portions of the HAZ.

Recommended Filler Metals for 1.4466 Welding

Recommended Filler Metals for Welding 1.4466 / X1CrNiMoN25-22-2
Welding Process	Recommended Filler / Electrode	Notes
GTAW (TIG)	AWS A5.9 ER25-22-2 / W25 22 2 N L	Preferred for root passes and precision welds. Use pure argon or Ar/2%N₂ shielding to maintain nitrogen content in weld metal.
GMAW (MIG)	AWS A5.9 ER25-22-2	Use Ar/2%N₂ shielding gas. Spray transfer mode preferred for production welding of thicker sections.
SMAW (MMA)	AWS A5.4 E25-22-2LN	For field welding and repair. Low hydrogen electrodes. Nitrogen addition in electrode formulation compensates for N losses during welding.
SAW (Submerged Arc)	AWS A5.9 ER25-22-2 with matching flux	For large weld deposits on thick sections. Flux choice is important to keep N content and avoid dilution issues.

Preheat & Interpass Temperature

1.4466 does not require preheating for welding (in contrast to carbon steels) which facilitates fabrication. The interpass temperature should be limited to below 150°C to avoid carbides being precipitated and sigma phase forming in multi-pass welds. Temperature indicating sticks or contact pyrometers should be used to confirm the interpass temperature between passes.

Post-Weld Heat Treatment

Post-weld heat treatment (PWHT) is not required for 1.4466 in standard applications, and stress-relief annealing at intermediate temperatures (500–800°C) should be avoided as it risks sigma phase precipitation and sensitization. If PWHT is specified for a specific reason, a full solution anneal at 1050–1100°C followed by rapid quenching is the only acceptable treatment.

Production Standards, International Certifications & Full-Process Quality Control

Applicable International Standards

Our 1.4466 forging parts are manufactured, tested and documented in full compliance with the following internationally recognized standards:

EN 10088-3: 2014 — Stainless steels: Technical delivery conditions for semi-finished products, bars, rods, wire, sections and bright products of corrosion resisting steels for general purposes. This is the primary material specification standard for 1.4466 round bars and open die forgings.
EN 10028-7: 2016 — Flat products made of steels for pressure purposes: Stainless steels. Referenced for plate and disc forgings used in pressure vessel construction.
EN 10250-4: 2000 — Open die steel forgings for general engineering purposes: Stainless and heat-resisting steels. Specifically covers the forging delivery requirements for 1.4466.
EN 10088-1: 2014 — Stainless steels: List of stainless steels. Defines the 1.4466 designation and composition limits.
ASTM A276 / A276M — Standard Specification for Stainless Steel Bars and Shapes. Referenced for projects with North American / ASME code requirements.
ASTM A479 / A479M — Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels.
API 6A (22nd Edition) — Specification for Wellhead and Christmas Tree Equipment. We produce forgings to the dimensional and material requirements referenced in API 6A, for incorporation into equipment manufactured by API 6A licensed manufacturers.
ASME Boiler & Pressure Vessel Code, Section II Part A — Referenced for ASME code pressure vessel construction projects.

Macrostructure Quality Acceptance Limits

Class	Defect Category	Maximum Acceptable Severity	Assessment Method
1	Freckles (segregation spots)	Grade A (per applicable chart)	Macroetch on transverse cross-section, visual per EN 10243-2
2	White Spots (hydrogen flakes)	Grade A	Macroetch, visual examination
3	Radial Segregation	Grade A	Macroetch, visual examination
4	Ring Pattern (banding)	Grade B	Macroetch, visual examination
5	Centre Porosity	Grade A	UT and macroetch cross-verification

Full-Process Quality Control & Testing Procedures

Every batch of 1.4466 forgings from Jiangsu Liangyi undergoes the following comprehensive test and inspection program before shipment — all conducted in our in-house CNAS-recognized testing laboratory or by accredited third parties:

Jiangsu Liangyi 1.4466 Stainless Steel Forging Production Line — Forging Press, Solution Annealing Furnace, Ultrasonic Testing (UT) and Dye Penetrant Inspection (PT) in progress at Jiangyin factory

Raw Material PMI (Positive Material Identification): Full OES (optical emission spectrometer) analysis of every incoming heat against EN 10088-3 composition limits. No material enters our production unless 100% compliant. Heat number traceability maintained from this point through every subsequent step.
In-Process Forging Temperature Monitoring: Thermocouple furnace charts and IR pyrometer surface temperature checks at each forging stage. Reheat cycles documented and cross-referenced to forging log.
Heat Treatment Certification: Full time-temperature chart for every furnace load, with pyrometer calibration certificate. Solution annealing temperature, hold time, and quench method documented on the heat treatment certificate attached to the MTR.
Visual Surface Inspection: 100% visual examination of all machined and forged surfaces per applicable EN or ASTM standard. Surface condition documented photographically for critical applications.
Dimensional Inspection: Full dimensional verification per customer drawing using calibrated instruments including CMM (Coordinate Measuring Machine) for complex geometries, calibrated manual instruments for standard features. All dimensional records retained.
Ultrasonic Testing (UT): 100% volumetric UT examination per EN 10228-3 / ASTM A388 / API 6A or customer specification. Flaw acceptance per applicable class (typically Grade 3 or better). UT performed by Level II or III certified personnel.
Dye Penetrant Testing (PT): 100% surface PT (visible or fluorescent) per EN ISO 3452 / ASTM E165, on all accessible surfaces after final machining. Acceptance per EN ISO 23277 or customer specification.
Magnetic Particle Testing (MT): Where specified for additional surface and near-surface defect detection on machined surfaces.
Radiographic Testing (RT): Where specified by customer for weld zone qualification or complex forging sections with limited UT access.
Tensile Testing: Tensile strength (Rm), 0.2% proof strength (Rp0.2), and elongation (A) tested per EN ISO 6892-1 / ASTM E8 on specimens from approved sampling locations as defined by the applicable product standard.
Charpy V-Notch Impact Testing: Sets of 3 specimens per sampling direction, tested at specified temperature (room temperature standard; −196°C for cryogenic qualification; or customer-specified temperature). Per EN ISO 148-1 / ASTM E23.
Hardness Testing: Brinell (HB) hardness per EN ISO 6506-1 / ASTM E10. Vickers microhardness (HV) available for weld zone and HAZ qualification.
Metallographic Examination: Macro and micro structure examination per EN 1321 / ASTM E407 where required. Grain size determination per EN ISO 643 / ASTM E112. Available for every heat upon customer request.
Intergranular Corrosion (IGC) Testing: Huey test per ASTM A262 Practice C (boiling 65% HNO₃, 5 × 48-hour cycles) or Strauss test per ASTM A262 Practice E (boiling H₂SO₄/CuSO₄). Available as standard IGC qualification for urea-grade material.
Pitting Corrosion Testing: ASTM G48 Method A (FeCl₃ immersion) for pitting resistance qualification where specified.
Ferrite Content Measurement: Feritscope measurement for delta-ferrite content quantification. 1.4466 should measure <1% delta-ferrite; any significant ferrite content is an indicator of chemical composition deviation or incorrect heat treatment.

Documentation & Traceability — EN10204 3.1 and 3.2 Certification

Every 1.4466 forging delivered by Jiangsu Liangyi is accompanied as standard by an EN10204 3.1 Material Test Report (MTR) certified by our authorized Quality Control representative, covering all required chemical composition results, mechanical test results, heat treatment records, NDT results, and dimensional certification. The MTR includes the heat number, melt number, forging number, and our internal production batch number, allowing complete forward and backward traceability through our quality management records.

EN10204 3.2 certification — involving independent confirmation of all test results by an authorized third-party inspection organization — is available upon customer request at a modest additional charge. We can facilitate source inspection and witness testing by internationally recognized third-party agencies — including TUV Rheinland, Bureau Veritas (BV), SGS, Lloyd's Register (LR), DNV, Applus+, RINA, and any other agency nominated by the customer.

How to Order Custom 1.4466 Forgings — A Practical Guide for Engineers & Procurement Teams

When you order custom forgings, especially a specialised, safety-critical grade such as 1.4466, it is important to communicate your technical requirements clearly to ensure that the final product meets your design intent. From our more than 25 years of experience responding to customer inquiries around the globe, we have learned what information is most important to include in your inquiry to obtain the quickest and most accurate response:

Required Information for a Quotation

Material specification: Confirm "1.4466 per EN 10088-3" or "X1CrNiMoN25-22-2" (and any supplementary requirements, e.g., P ≤0.020%, IGC test)
Product form: Bar / ring / disc / sleeve / valve body / custom forging — with sketch or drawing
Key dimensions: OD, ID (if hollow), length/height, weight (estimated), tolerances
Delivery condition: Rough forged (+A), rough machined, or finish machined to drawing
Quantity & delivery schedule: Number of pieces and required delivery date
Certification level: EN10204 3.1 (standard) or EN10204 3.2 (with third-party)
Application / end use: Helps us identify any supplementary testing that may be required

Optional Supplementary Requirements

Intergranular corrosion test (Huey / Strauss) — for urea plant qualification
Charpy impact at temperature other than room temperature (e.g., −196°C for cryogenic)
Pitting resistance test per ASTM G48
Ferrite content measurement (<1% target)
Third-party source inspection witness at forging, heat treatment or testing stage
HIC (Hydrogen Induced Cracking) resistance testing for sour service oil & gas
Phosphorus ≤0.020% special restriction for critical urea service
Specific dimensional or testing documentation requirements for API 6A licensed equipment applications
Material documentation for sour service (NACE MR0175 / ISO 15156-3 material requirements are met by standard production conditions — hardness ≤240 HB, solution-annealed)

Typical Lead Time: Standard 1.4466 forgings with readily available heat inventory: 4–8 weeks from PO to shipment. Custom large forgings (>5,000 kg) requiring fresh melt and production scheduling: 10–16 weeks. Rush production for smaller, critical-path items can sometimes be accommodated — contact our sales team to discuss your specific timeline requirement.

Minimum Order Quantity: We accept orders from single-piece custom forgings for prototype and project development, through to production batches of hundreds or thousands of pieces for series production components.

Frequently Asked Questions — 1.4466 (X1CrNiMoN25-22-2) Forgings

What exactly is 1.4466 steel, and why is it called "urea grade"?

1.4466 (X1CrNiMoN25-22-2 per EN 10088) is a high-alloy, fully austenitic stainless steel specifically engineered for extreme corrosion resistance in urea synthesis environments. The "urea grade" designation reflects its principal application: resistance to ammonium carbamate (NH₂COONH₄), the highly corrosive intermediate compound formed during urea production at temperatures up to 185°C and pressures up to 200 bar.

The key to its performance is the combination of ultra-low carbon (≤0.020%), which prevents grain boundary sensitization (intergranular carbide precipitation), with high chromium (24–26%), high nickel (21–23%), molybdenum (2–2.5%), and nitrogen (0.10–0.16%) — a chemistry that was specifically developed after standard austenitic stainless steels like 316L proved inadequate for urea service. It is sometimes called 2RE69 using the Swedish Sandvik designation, but the EN 1.4466 / X1CrNiMoN25-22-2 designation is the universal reference today.

How does 1.4466 compare to 316L in urea plant service, and can 316L ever substitute for 1.4466?

316L absolutely cannot substitute for 1.4466 in urea synthesis high-pressure service. The corrosion mechanisms are fundamentally different: in ammonium carbamate, 316L suffers rapid intergranular corrosion (IGC) because its carbon content (up to 0.030%), while considered "low" by general stainless steel standards, is sufficient to cause M₂₃C₆ carbide precipitation at grain boundaries during any elevated-temperature exposure. Once sensitized, the chromium-depleted grain boundary zones corrode rapidly in ammonium carbamate, causing complete component failure within months rather than the years expected from 1.4466.

In standard Huey test (boiling 65% nitric acid per ASTM A262 Practice C), published corrosion literature consistently shows that 316L corrodes at substantially higher rates than 1.4466 — a significant multiple difference that reflects the fundamental microstructural vulnerability of 316L to intergranular attack in oxidizing acidic media. In actual ammonium carbamate service, the difference in performance is even more pronounced because the attack mechanism specifically targets the weakest microstructural feature (grain boundaries) of the less resistant material. No amount of specification-stretching or process modification makes 316L acceptable for urea synthesis high-pressure components.

Is 1.4466 suitable for cryogenic service down to −196°C (liquid nitrogen temperature)?

Yes, 1.4466 is fully qualified for cryogenic service down to −196°C, and this is one of its significant secondary application areas. As a fully austenitic stainless steel with no ferrite or martensite, 1.4466 does not exhibit a ductile-to-brittle transition temperature (DBTT) — the phenomenon that causes ferritic and martensitic steels to become suddenly brittle at low temperatures. The austenitic face-centered cubic (FCC) crystal structure maintains atomic-level plasticity down to absolute zero temperature.

The EN 10088-3 standard guarantees a minimum transverse Charpy V-notch impact energy of ≥60 J at −196°C for 1.4466 in solution-annealed condition. Our production experience confirms that solution-annealed 1.4466 forgings comfortably satisfy this requirement (actual values documented in individual EN10204 3.1 MTRs issued per production heat). This performance meets the requirements of EN 1626 (valves for cryogenic service), EN 13458 (cryogenic vessels), and the cryogenic sections of ASME BPVC — making 1.4466 forgings directly applicable to LNG pump casings, cryogenic valve bodies, cold box piping components, and liquid nitrogen storage system components.

What is the maximum ring size and forging weight that Jiangsu Liangyi can produce in 1.4466?

For seamless rolled rings in 1.4466, our maximum outer diameter capability is 6,000 mm (6 meters), with a maximum single-piece weight of 30,000 kg (30 tons). We can produce rings in rectangular, flanged (T-section), L-section, and custom profiled cross-sections within this size envelope. Minimum outer diameter for our ring rolling process is approximately 200 mm.

For open die forgings (bars, discs, shafts, hollow cylinders), the maximum single-piece forging weight is also 30,000 kg, with maximum bar diameter up to 2,000 mm and maximum length up to 15,000 mm. Disc and plate forgings up to 3,000 mm diameter and 800 mm thickness are achievable. For very large components approaching these limits, we recommend early engagement with our technical team to assess forging feasibility, equipment scheduling, and heat treatment logistics.

What certifications and inspection documentation do you provide for 1.4466 forgings?

Standard delivery includes an EN10204 3.1 Material Test Report (MTR) certified by our authorized QC representative, covering: full chemical composition (all elements per EN 10088-3 including C, Cr, Ni, Mo, N, Mn, Si, P, S), tensile test results (Rm, Rp0.2, A), Charpy impact test results (KV at specified temperature), hardness results, NDT reports (UT, PT and any other tests performed), heat treatment certificate (with time-temperature chart), dimensional inspection report, and full heat number and production traceability data.

EN10204 3.2 certification — with all test results counter-certified by an independent third-party inspection body — is available on request. We can facilitate source inspection and witness testing by customer-nominated third-party agencies including TUV Rheinland, Bureau Veritas, SGS, Lloyd's Register, DNV, Applus+ RTD, RINA, and others. EN10204 3.2 certificates are jointly issued by the customer's nominated third-party inspection body and our QC team — we do not unilaterally issue 3.2 documents.

Do you perform intergranular corrosion (IGC) testing on 1.4466 forgings?

Yes. IGC testing is available and commonly requested for urea-grade 1.4466 applications. We perform both the Huey test (ASTM A262 Practice C — exposure to boiling 65% nitric acid for 5 × 48-hour cycles) and the Strauss test (ASTM A262 Practice E — copper sulfate / sulfuric acid immersion). The Huey test is the most widely specified IGC test for urea plant material qualification and is sometimes mandated by the process licensor or EPC contractor as part of the incoming material approval process.

For properly manufactured 1.4466 with C ≤0.020% and correct solution annealing, passing the Huey test is routine. Actual IGC test results are documented in the EN10204 3.1 MTR when this test is performed, and tested specimens and preparation records are retained in our QA archive for customer reference.

What is the ASTM or UNS equivalent of 1.4466 (X1CrNiMoN25-22-2)?

There is no direct formal ASTM UNS equivalent for X1CrNiMoN25-22-2 with the same composition window. The closest ASTM UNS designation is UNS S31050, which covers austenitic stainless steels with a similar high-chromium, high-nickel, molybdenum and low-carbon chemistry in the urea-grade category. However, the exact composition limits differ slightly between the EN and ASTM systems. For projects specified to ASME BPVC that require 1.4466-equivalent material, the ASME material specification is normally quoted as a special material within ASME Section II Part D. The customer’s engineering team will set the chemical composition requirements directly from EN 10088-3 and confirm applicability with the ASME Authorized Inspector.Our technical department can assist customers with material equivalency documentation for ASME code projects upon request.

Can 1.4466 forgings be used in API 6A sour service (H₂S-containing) applications?

Yes. 1.4466 is listed in NACE MR0175 / ISO 15156-3 as an acceptable material for use in oil and gas production environments containing H₂S, subject to specific hardness and heat treatment requirements. The fully austenitic microstructure of 1.4466 makes it inherently more resistant to hydrogen embrittlement (HIC and SSC mechanisms) than martensitic or precipitation-hardened stainless steels, and significantly more resistant than carbon steels or low-alloy steels in sour environments.

For sour service applications, our 1.4466 forgings are produced with hardness maintained at ≤240 HB, in the solution-annealed condition — both consistent with the requirements of NACE MR0175 / ISO 15156-3 for austenitic stainless steels. Hardness test results and heat treatment certificates are included in the EN10204 3.1 MTR as standard. Where customers require additional assurance, we can supplement the standard mechanical testing with Hydrogen-Induced Cracking (HIC) resistance testing per NACE TM0284 and Sulfide Stress Corrosion Cracking (SSC) resistance testing per NACE TM0177 Method A.

What surface finish options are available for 1.4466 forgings?

We supply 1.4466 forgings in the following surface conditions: (1) As-forged / as-heat-treated — de-scaled surface, suitable for further machining; (2) Rough-machined — with machining allowance of typically 3–10 mm per surface removed to clean, metallurgically sound material beneath any forging scale; (3) Finish-machined to drawing — full CNC turning, milling, drilling, boring and grinding to customer drawing dimensions and specified tolerances; (4) Ground and polished — fine surface finish (Ra 1.6, 0.8, or 0.4 µm) for sealing surfaces, bearing journals, and precision fits; and (5) Electro-polished — for applications in pharmaceutical, food-grade, and ultra-high-purity environments where maximum corrosion resistance and cleanliness are required.

For sealing surfaces on valve bodies, flanges, and pressure vessel nozzles, we can machine to specified flatness, parallelism, and surface roughness tolerances verified by calibrated profilometer and CMM. Ring groove dimensions for API ring joint gaskets (RTJ) are machined to the dimensional tolerances specified in API 6A, as required by our customers' API 6A licensed manufacturers.

What is 2RE69 and is it the same as 1.4466?

2RE69 is the Sandvik (Swedish) proprietary designation for their version of the high-Cr, high-Ni, ultra-low carbon, Mo-N alloyed urea-grade stainless steel. It corresponds closely to the EN designation 1.4466 / X1CrNiMoN25-22-2. While the underlying alloy concept is the same, the exact composition limits between "2RE69" (a Sandvik-specific controlled composition) and "1.4466 per EN 10088-3" (a standardized European specification) may differ slightly at the boundary values.

When customers specify "2RE69 equivalent" or "2RE69 per EN 10088-3," we supply material conforming to the EN 10088-3 1.4466 composition and property requirements — the standard that governs commercial supply from independent forging manufacturers such as Jiangsu Liangyi. If a project specification explicitly requires Sandvik 2RE69 as a trade-name material (not equivalent), the customer should contact Sandvik directly for their material supply. In the vast majority of practical urea plant projects, "EN 1.4466" and "2RE69-equivalent" are used interchangeably and our material has been accepted by the major process licensors and EPC contractors.

Contact Jiangsu Liangyi — Request a 1.4466 Forging Quotation

Whether you are specifying materials for a new urea plant, sourcing replacement forgings for a plant turnaround, or qualifying a new supplier for your approved vendor list, the Jiangsu Liangyi technical and commercial team is ready to support you. Send your drawings, technical specifications, and quantity requirements to receive a detailed quotation with typical production lead time, full material traceability information, and a completed material compliance confirmation against your specification. Our technical engineers can also review your material specification and application requirements and provide written technical recommendations — at no charge — to help ensure the best possible outcome for your project.

Inquiry Email: sales@jnmtforgedparts.com

Phone / WhatsApp: +86-13585067993

Office Tel: +86-510-86107550

Official Website: www.jnmtforgedparts.com

Factory Address: Chengchang Industry Park, Jiangyin City, Jiangsu Province, 214400, China

Business Hours: Monday – Friday, 08:00 – 18:00 (CST, UTC+8)