S32304 Lean Duplex Stainless Steel Pipe,310H stainless steel tube,S31803 Stainless Steel Pipes,high-temperature stainless steel tube

Key Features of S32304 Lean Duplex Stainless Steel Pipe

Excellent Stress Corrosion Cracking Resistance: Outstanding resistance to chloride-induced SCC, significantly outperforming 304 and 316L in chloride-containing environments, especially at elevated temperatures.

1. High Mechanical Strength: Minimum yield strength of ≥ 400 MPa (approximately twice that of 304/304L), allowing for thinner wall sections, weight reduction, and lower material costs.

2. Good Pitting and Crevice Corrosion Resistance: PRE (Pitting Resistance Equivalent) ≥ 24, providing reliable service in environments with moderate chloride concentrations, outperforming 304 and comparable to 316 in many applications.

3. Low Nickel Content – Cost Stability: With nickel content of only 3.0–5.5% (compared to 8–10% for 304 and 10–14% for 316), S32304 offers greater price stability and lower material cost than austenitic grades.

4. Excellent Weldability: Maintains balanced ferrite/austenite ratio in the weld zone with proper welding procedures, and can be welded to austenitic grades using appropriate filler metals.

5. Good Low-Temperature Toughness: Maintains adequate impact toughness down to -40°C, suitable for many structural and pressure vessel applications.

6. High Resistance to Erosion and Wear: Higher hardness and strength provide improved resistance to erosion and wear compared to austenitic stainless steels.

7. International Certification: Pipes can be certified by ABS, BV, DNV, LR, GL, RINA, CCS, KR, and NK, and comply with NORSOK M-630 standards for offshore and marine applications.

S32304 Lean Duplex Stainless Steel Pipe Related International Standards and Grades

Womic Steel’s S32304 lean duplex pipes conform to multiple international specifications for pressure service, structural applications, and corrosive environments:

Standard	Description	Equivalent Grade / Material Number
ASTM A789 / A790	Seamless and welded ferritic/austenitic stainless steel pipe	S32304
ASTM A928	Welded ferritic/austenitic pipe for corrosive service	S32304
EN 10216-5	Seamless stainless steel tubes for pressure purposes	1.4362 (X2CrNiN23-4)
EN 10217-7	Welded stainless steel tubes for pressure purposes	1.4362 (X2CrNiN23-4)
DIN 17458	Austenitic seamless tubes (duplex supplement)	X2CrNiN23-4
JIS G3459 / G3463	Stainless steel pipes for general and heat-resisting use	SUS329J1L (similar)
GB/T 21833	Seamless and welded duplex stainless steel pipes	022Cr23Ni4MoCuN
ISO 17781	Duplex stainless steel pipes for petroleum and natural gas industries	1.4362
NORSOK M-630	Material data sheets for duplex stainless steel	Grade D (S32304)

These standards ensure that S32304 lean duplex pipes meet global requirements for chemical composition, balanced dual-phase microstructure, mechanical performance, testing, and dimensional accuracy.

Chemical Composition of S32304 Lean Duplex Stainless Steel Pipe

Element	C	Mn	P	S	Si	Cr	Ni	Mo	N	Cu
S32304	≤0.030	≤2.50	≤0.040	≤0.010	≤1.00	21.5–24.5	3.0–5.5	0.05–0.60	0.05–0.20	0.05–0.60

Note: S32304 is a lean duplex grade with lower nickel and molybdenum content than standard duplex (2205). The high chromium content (21.5–24.5%) and nitrogen addition provide excellent corrosion resistance and mechanical strength despite the lower alloy content. The reduced nickel content makes this grade less susceptible to price volatility while maintaining performance in moderate chloride environments.

Pitting Resistance Equivalent (PRE) Calculation:
PRE = %Cr + 3.3 × %Mo + 16 × %N ≥ 24 (typically 24–27)

Comparison of PRE Values:

1) 304/304L: PRE ≈ 18–19

2) 316/316L: PRE ≈ 24–26

3) S32304 (2304): PRE ≈ 24–27

4) S32205 (2205): PRE ≥ 34

S32304 Lean Duplex Stainless Steel Pipe Mechanical Properties and Heat Treatment Requirements

Property	Unit	S32304
Tensile Strength (min)	MPa	≥600
Yield Strength (0.2% offset, min)	MPa	≥400
Elongation (min)	%	≥25
Hardness (Brinell, max)	HBW	≤290
Hardness (Rockwell C, max)	HRC	≤30
Density	g/cm³	7.80
Melting Range	°C	1350–1400

Impact Toughness (Charpy V-Notch, typical at -40°C):

Longitudinal: ≥ 60 J (typical)

Heat Treatment Condition:
S32304 lean duplex pipes are solution annealed at 980–1040°C followed by rapid cooling (water quenching or rapid air cooling) . This heat treatment:

1. Restores the balanced 40–60% ferrite / 40–60% austenite microstructure.

2. Dissolves unwanted intermetallic phases that can reduce corrosion resistance and toughness.

3. Relieves internal stresses from forming, rolling, or welding.

4. Ensures optimal mechanical properties and corrosion performance.

5. Note: Compared to S32205 (2205) which requires higher annealing temperatures (1040–1120°C), S32304 has a lower solution annealing temperature range (980–1040°C) due to its lower alloy content. This makes heat treatment more economical and easier to control.

6. Delivery Condition: Pipes are normally supplied in solution annealed and pickled condition. Upon request, bright annealed or polished finishes can be provided for specific applications.

Manufacturing Process of S32304 Lean Duplex Seamless Steel Pipe

Womic Steel adopts advanced production technology to ensure each S32304 lean duplex seamless pipe meets exact specifications with balanced microstructure and excellent surface quality.

1. Raw Material Selection: High-quality S32304 lean duplex billets from certified mills (Baosteel, TISCO, Outokumpu, POSCO) with certified chemical composition and ferrite/austenite balance.

2. Heating and Piercing: Billets heated to controlled temperature (lower than austenitic grades to prevent ferrite coarsening) and pierced using a rotary piercing mill.

3. Hot Rolling: Shells elongated and rolled to desired intermediate size.

4. Cold Drawing / Cold Pilgering: Pipes refined to precise dimensions with improved surface finish and enhanced mechanical properties.

5. Solution Annealing: Heat treatment at 980–1040°C followed by rapid cooling to restore balanced duplex structure.

6. Pickling & Passivation: Removal of oxides and creation of passive film; standard pickling acids suitable for lean duplex grades.

7. Straightening and Dimensional Calibration: Ensures consistent roundness and wall uniformity.

8. Final Inspection & Marking: Each pipe tested (including ferrite content measurement), marked with grade, heat number, and standard before packing.

This process guarantees a balanced dual-phase microstructure, smooth internal bore, high structural integrity, and excellent corrosion resistance across all batches of Womic Steel’s S32304 Lean Duplex Seamless Pipe.

Manufacturing Process of S32304 Lean Duplex Welded Steel Pipe

Womic Steel utilizes state-of-the-art manufacturing technology to ensure every S32304 lean duplex welded pipe meets precise specifications with weld zone phase balance and excellent surface quality.

1. Raw Material Selection: High-quality S32304 lean duplex stainless steel strips/coils from certified suppliers.

2. Slitting & Uncoiling: The steel coil is slit to the required width and uncoiled for feeding into the forming mill.

3. Forming & Welding: The strip is progressively formed into a cylindrical shape. The edges are welded using advanced TIG or Plasma welding with appropriate heat input control and shielding gas (Ar + N₂) to maintain weld zone phase balance.

4. Weld Seam Treatment: External weld bead removal and optional internal bead control.

5. Solution Annealing: Full heat treatment of the entire welded pipe at 980–1040°C followed by rapid cooling – essential for restoring corrosion resistance and balanced microstructure in the weld and HAZ.

6. Sizing & Calibration: Final precise outer diameter and roundness.

7. Pickling & Passivation: Chemical treatment removes scale and promotes passive layer formation, including the weld zone.

8. Non-Destructive Testing (NDT) : Weld seam inspected using Eddy Current or Ultrasonic Testing.

9. Ferrite Content Measurement: Verification of weld and base metal phase balance (typically 35–65% ferrite).

10. Final Inspection & Marking: Complete dimensional check, visual inspection, and traceable marking.

This controlled process guarantees a sound weld seam, excellent dimensional accuracy, balanced duplex microstructure, and reliable corrosion resistance for every batch of Womic Steel’s S32304 Lean Duplex Welded Pipe.

S32304 Lean Duplex Stainless Steel Pipe Dimensions and Tolerances

1. Outside Diameter: 6mm – 1219mm (1/4″ – 48″)

2. Wall Thickness: 0.5mm – 40mm (SCH 5S – SCH XXS

3. Length: Up to 12m (fixed or random); longer lengths available upon request

4. Tolerances: According to ASTM A999 / EN ISO 1127

ANSI B 36.19/ANSI B36.10 DIMENSIONS OF SEAMLESS &WELDED STAINLESS STEEL PIPE
Nominalsize		mm	ANSIB36.19				ANSIB36.10ANSIB36.10
DN	NPS	mm	5S	10S	40S	80S	10	20	30	STD	40	60	XS	80	100	120	140	160XXS
6	1/8"	10.29		1.24	1.73	2.41				1.73	1.73		2.41	2.41
8	1/4"	13.72		1.65	2.24	3.02				2.24	2.24		3.02	3.02
10	3/8"	17.15		1.65	2.31	3.20				2.31	2.31		3.20	3.20
15	1/2"	21.34	1.65	2.11	2.77	3.73				2.77	2.77		3.73	3.73				4.78	7.47
20	3/4"	26.67	1.65	2.11	2.87	3.91				2.87	2.87		3.91	3.91				5.56	7.82
25	1"	33.4	1.65	2.77	3.38	4.55				3.38	3.38		4.55	4.55				6.35	9.09
32	1 1/4"	42.16	1.65	2.77	3.56	4.85				3.56	3.56		4.85	4.85				6.35	9.70
40	1 1/2"	48.26	1.65	2.77	3.68	5.08				3.68	3.68		5.08	5.08				7.14	10.16
50	2"	60.33	1.65	2.77	3.91	5.54				3.91	3.91		5.54	5.54				8.74	11.07
65	2 1/2"	73.03	2.11	3.05	5.16	7.01				5.16	5.16		7.01	7.01				9.52	14.02
80	3"	88.9	2.11	3.05	5.49	7.62				5.49	5.49		7.62	7.62				11.13	15.24
90	3 1/2"	101.6	2.11	3.05	5.74	8.08				5.74	5.74		8.08	8.08
100	4"	114.3	2.11	3.05	6.02	8.56				6.02	6.02		8.56	8.56		11.13		13.50	17.12
125	5”	141.3	2.77	3.40	6.55	9.52				6.55	6.55		9.52	9.52		12.70		15.90	19.05
150	6"	168.28	2.77	3.40	7.11	10.97				7.11	7.11		10.97	10.97		14.30		18.20	21.95
200	8"	219.08	2.77	3.76	8.18	12.70		6.35	7.04	8.18	8.18	10.30	12.70	12.70	15.10	18.20	20.60	23.00	22.22
250	10"	273.05	3.40	4.19	9.27	12.70		6.35	7.80	9.27	9.27	12.70	12.70	15.09	18.26	21.44	25.40	28.58
300	12"	323.85	3.96	4.57	9.52	12.70		6.35	8.38	9.52	10.31	14.27	12.70	17.48	21.44	25.40	28.58	33.32
350	14"	355.6	3.98	4.78			6.35	7.92	9.52	9.52	11.13	15.09	12.70	19.05	23.83	27.79	31.75	35.71
400	16"	406.4	4.19	4.78			6.35	7.92	9.52	9.52	12.70	16.66	12.70	21.44	26.19	30.96	36.53	40.49
450	18"	459.2	4.19	4.78			6.35	7.92	11.13	9.52	14.27	19.05	12.70	23.83	29.36	34.92	39.67	45.24
500	20"	508	4.77	5.53			6.35	9.52	12.70	9.52	15.09	20.62	12.70	26.19	32.54	38.10	44.45	50.01
550	22"	558.8	4.77	5.53			6.35	9.52	12.70	9.52	15.87	22.22	12.70	28.57	34.92	41.27	47.62	53.97
600	24"	609.6	5.54	6.35			6.35	9.52	14.70	9.52	17.48	24.61	12.70	30.96	38.89	46.02	52.37	59.94
650	26"	660.4					7.92	12.70		9.52			12.70
700	28"	711.2					7.92	12.70	15.88	9.52			12.70
750	30"	762	6.35	7.92			7.92	12.70	15.88	9.52			12.70
800	32"	812.8					7.92	12.70	15.88	9.52			12.70

*(Refer to ANSI B36.19 / B36.10 dimension tables for detailed schedule matching)*

Surface Conditions of S32304 Lean Duplex Stainless Steel Pipe

Womic Steel offers a wide range of surface finishes to meet various industrial, structural, and architectural applications.

Surface Type	Description
Annealed & Pickled (AP Finish)	Standard industrial finish – matte, oxide-free after acid treatment. Suitable for most process piping and structural applications.
Bright Annealed (BA Finish)	Mirror-like surface obtained through controlled atmosphere annealing – available for smaller diameter pipes.
Polished Finish (180#, 240#, 320#, 400#, 600#)	Smooth mechanical finish suitable for decorative, architectural, and food processing applications.
Mirror Polished (8K)	Ultra-reflective surface for sanitary, architectural, and high-end design applications.
Brushed / Hairline Finish	Satin linear texture for furniture, railings, and interior design.
Passivated Finish	Surface chemically treated to enhance corrosion protection.
Grit Blasted / Bead Blasted	Matte, uniform surface texture for structural and industrial environments.

Each S32304 pipe surface is inspected for uniform appearance, absence of pits, and consistent finish quality.

Testing and Inspection of S32304 Lean Duplex Stainless Steel Pipe

Every S32304 lean duplex stainless steel pipe undergoes comprehensive inspection in accordance with ASTM, EN, and GB standards, including duplex-specific tests, to guarantee reliability and performance:

Test / Inspection	Description	Applicability
Visual & Dimensional Inspection	Surface, roundness, wall thickness, straightness, and end preparation	100%
Hydrostatic Pressure Test	Leakage and pressure resistance verification	100%
Eddy Current Test (ECT)	Surface and sub-surface imperfection detection	100% (seamless)
Ultrasonic Test (UT)	Internal integrity of pipe wall and weld seam	100%
Positive Material Identification (PMI)	Confirms correct chemical grade (Cr, Ni, Mo, N verification)	100%
Ferrite Content Measurement	Magnetic induction or metallographic method – requirement: 35–65% ferrite	100%
Microstructure Examination	Verification of balanced dual-phase structure, absence of intermetallic phases	Per heat / batch
Tensile Testing	Confirms ≥600 MPa UTS and ≥400 MPa yield strength	Per heat / batch
Hardness Testing	Brinell or Rockwell – max ≤290 HBW / ≤30 HRC	Per heat / batch
Charpy Impact Testing	Verifies low-temperature toughness at -40°C (as specified)	Per heat (optional)
Intergranular Corrosion Test (IGC)	Validates resistance to sensitization	Optional
Surface Roughness Check	For polished or special finish requirements	As required
Third-Party Inspection	SGS / BV / DNV / TUV – witnessed testing and certification	Upon customer request

These extensive tests ensure that every S32304 Lean Duplex Stainless Steel Pipe from Womic Steel meets the highest international standards for reliability, corrosion resistance, and longevity.

Applications of S32304 Lean Duplex Stainless Steel Pipe

S32304 lean duplex stainless steel pipe is an ideal cost-effective alternative to 304 and 316L for applications requiring higher strength and good corrosion resistance. Womic Steel supplies to global projects with certifications available from all major classification societies.

Industry	Typical Applications
Hot Water and Pressure Vessels	Hot water storage tanks, pressure vessels, boilers – where SCC resistance is required at elevated temperatures
Structural and Construction	Bridge components, handrails, support structures, architectural facades – high strength allows reduced section thickness
Food and Beverage Processing	Processing tanks, piping systems, brewing equipment – where cleanability and corrosion resistance are essential
Heat Exchangers	Shell-and-tube heat exchangers, plate heat exchangers – good thermal conductivity and strength
Chemical Processing	Dilute acid handling, organic chemical processing – moderate corrosion resistance at lower cost
Marine and Offshore	Seawater piping (moderate exposure), ballast systems, firewater lines – certified by ABS, BV, DNV, LR, GL, RINA, CCS, KR, NK
Water Treatment	Freshwater and brackish water handling, reverse osmosis systems
Pulp and Paper	Process piping in non-bleach areas, water handling systems
Mining and Mineral Processing	Slurry lines, process water systems – where wear resistance is important
Transportation	Tanker trucks, rail cars – weight reduction through higher strength
Architectural and Decorative	Railings, canopies, building cladding – aesthetic finishes available

S32304 Lean Duplex Stainless Steel Pipe Packing, Delivery, and Womic Steel’s Transportation Advantage

Each S32304 lean duplex stainless steel pipe is securely packed and clearly labeled to ensure safe and efficient transport worldwide.

General packaging for local truck transport:
Bundle packing with woven fabric, iron strip bundle, plastic cap on both ends.

Hexagonal packaging:
Bundle packing with woven fabric, iron strip bundle, plastic cap on two ends.

Packaging for welded pipe in medium and large sizes:
Wrapped with woven fabric by automatic packaging for export sea-worthy transport.

Packaging for medium and large size welded pipes for export:
Wooden or steel crate packaging for export sea-worthy transport.

General packaging for products to be exported:
Wooden box for export sea-worthy transport.

Packaging for precision tubes and heat exchanger tubes:
Wooden box for both local truck and export sea-worthy transport.

Womic Steel’s Shipping and Delivery Strengths for S32304 Lean Duplex Pipe:

1. Direct cooperation with global shipowners ensures the most competitive freight rates.

2. Professional loading and securing teams guarantee damage-free shipment.

3. Efficient document preparation – includes EN 10204 3.1 certificates and material test reports (MTR) – minimizing customs delays.

4. Rapid delivery time – standard sizes of S32304 maintained in ready stock; large inventory ensures quick dispatch.

5. Continuous cargo tracking and after-sales follow-up to ensure smooth arrival at destination.

Why Choose Womic Steel’s S32304 Lean Duplex Stainless Steel Pipe

Womic Steel is a trusted manufacturer and exporter specializing in lean duplex stainless steel pipes, committed to delivering premium quality, cost-effective solutions, and professional service.

1. Strict quality control under ISO 9001 and PED 2014/68/EU certification.

2. Lean duplex expertise – specialized knowledge in phase balance control and heat treatment of low-nickel duplex grades.

3. Modern production lines – cold pilger mills and automatic TIG welding lines.

4. Complete testing, inspection, and documentation support – including ferrite measurement and full traceability.

5. Cost-effective alternative – lower nickel content provides price stability and lower material cost compared to 304 and 316L, while offering higher strength.

6. Flexible customization – special diameters, wall thicknesses, lengths, and surface finishes (polished, brushed, mirror).

7. Fast production cycle – efficient manufacturing for both seamless and welded lean duplex pipes.

8. Reliable global shipping to all major ports worldwide.

9. Direct mill pricing – no middlemen, ensuring competitive costs.

Contact Womic Steel

For inquiries, technical support, or to request a quotation for your specific clad pipe requirements, please contact us:

Website: www.womicstainless.com

E‑mail: info@womicstainless.com

Tel / WhatsApp / WeChat:

Victor: +86 15575100681

Jack: +86 18390957568

Womic Steel – Your reliable partner for high‑quality stainless steel seamless pipes, metallurgically bonded clad tubes, and custom solutions for corrosion‑resistant applications.