UNS S32750 Super Duplex flanges Supplier in India

Q: The difference between S32750 (F53) and S32760 (F55) flanges?

Both S32750 (F53) and S32760 (F55) are Super Duplex stainless steel grades with similar duplex microstructures. S32750 (F53), known as Super Duplex 2507, is widely used in offshore and desalination applications as the standard Super Duplex grade. S32760 (F55) contains additional Tungsten and Copper, which increases its PREN values and enhances performance in more acidic or sour environments. S32760 is also commonly selected to meet historical standards such as ZERON 100.

Q: What are the criteria of Super Duplex flanges?

Super Duplex flanges are manufactured according to ASTM A182 / ASME SA182 standards. Dimensions up to 24 inches typically follow ASME B16.5, while larger sizes (26–60 inches) are based on ASME B16.47 Series A or B. Flanges can also be supplied according to EN 1092-1 and API 6A standards.

Q: Will these flanges work in sea water?

Yes. UNS S32750 flanges are specifically engineered for seawater environments with a PREN above 40. They offer excellent resistance to pitting and crevice corrosion, which would quickly damage Grade 316 stainless steel in similar conditions.

Q: What are some of the flange face types you supply?

We supply all major flange face types, including Raised Face (RF), Flat Face (FF), and Ring Type Joint (RTJ). RTJ flanges are commonly used in high-pressure Super Duplex applications (Class 900# to 2500#) to ensure a reliable metal-to-metal seal.

Solitaire Overseas is a specialized manufacturer, supplier and exporter of UNS S32750 / 2507 and UNS S32760 flanges (super duplex) that are designed to serve the critical piping connections in oil and gas, petrochemical, marine, power generation and desalination sector.

We have high-alloy Super Duplex stainless steel flanges that have a balanced austenitic-ferritic microstructure. Such a composition offers extremely high mechanical strength, outstanding resistance to pitting and crevice corrosion and to stress corrosion cracking (SCC). We also produce the entire line of Weld Neck, Slip-On, Blind, Socket Weld, and Threaded flanges.

The manufacturing and testing of all Super Duplex flanges UNS S32750 are done in strict adherence to ASTM A182 / ASME SA182 (Grade F53). Dimensional standards follow ASME/ANSI B16.5 (up to 24" diameter) and ASME B16.47 ( Series A and B when greater diameter is required ) and are fully compatible with international standards of piping code and project requirements.

Solitaire Overseas offers high quality Super Duplex flanges to EPC contractors, fabricators and end-users in India, Middle East, Europe, Asia, Africa and the Americas. We have standard material grades of UNS S32750 (F53), and UNS S32760 (F55), at pressure class 150# to 2500 # on request.

We also supply matching Super Duplex UNS S32750 / S32760 pipes and tubes and Super Duplex UNS S32750 pipe fittings in order to provide full packages.

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Standard Specifications for Super Duplex Steel Flanges (UNS S32750 / S32760)
What are Super Duplex Flanges UNS S32750 / S32760?
Types of Super Duplex UNS S32750 / S32760 Flanges
Super Duplex Steel UNS S32750 / S32760 Chemical Composition
Mechanical Properties of Super Duplex UNS S32750 / S32760 Flanges
Super Duplex 2507 Equivalent Grades (UNS S32750 / S32760)
Major Characteristics and Advantages of Super Duplex UNS S32750 / 2507 Flanges
ASTM A182 s32750Super Duplex Flange Applications and Industries
Super Duplex Steel Flanges UNS S32760 – Countries We Export
Dimensions of Super Duplex UNS S32750 Flanges
Weight Chart Of Super Duplex UNS S32750/ F53 Flanges

Standard Specifications for Super Duplex Steel Flanges (UNS S32750 / S32760)

Specification Parameter	Technical Details
Material Grades	Super Duplex Stainless Steel UNS S32750 (F53) and UNS S32760 (F55)
Product Standard	ASTM A182 / ASME SA182 – Specification for Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and Valves
Dimensional Standards	ASME B16.5 (NPS ½" to 24"), ASME B16.47 Series A & B (NPS 26" to 60"), API 6A (Wellhead equipment), BS 4504, EN 1092-1
Pressure Classes	Class 150, 300, 600, 900, 1500, 2500
Size Range	½" NB to 48" NB (Custom larger sizes available on request)
Face Types	Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ), Tongue & Groove (T&G)
Manufacturing Routes	Forged and machined to final dimensions
Forms Available	Weld Neck, Slip-On, Blind, Socket Weld, Threaded, Lap Joint, Spectacle Blinds

What are Super Duplex Flanges UNS S32750 / S32760?

A new generation of austenitic-ferritic stainless steel, Super Duplex UNS S32750 (F53) / S32760 (F55) is superior to the conventional austenitic (300-series) and standard duplex grades in nearly every way. It is a unique duplex type of microstructure that incorporates the best of both worlds whereby the mechanical hard/strength properties of ferrite and corrosion resistance/ductility of austenite are combined. The S32750 flanges are super duplex, have high yield and tensile strength, high resistance to pitting and crevice corrosion (PREN >40), and are resistant to chloride-induced stress corrosion cracking.

Flanges of this grade, Weld Neck, Slip-On and Blind are used to connect, branch or terminate the high-pressure piping systems that are in a high-temperature and high-chloride environment where standard stainless steels are no longer reliable.

UNS S32760 (F55) is a very similar Super Duplex grade with slightly varied chemistry; generally having tungsten and increased copper. This alteration typically results in an even larger Pitting Resistance Equivalent Number (PREN), which provides a larger corrosion margin in the specifically harsh acidic chloride or sour service conditions.

UNS S32750 (2507/F53) is in reality the most common Super Duplex grade that is used in offshore, desalination, chemical processing, and power. UNS S32760 (F55) is applied when project requirements insist on it or when it is needed to be compatible with older F55 equipment.

Solitaire Overseas has been producing and stocking Super Duplex UNS S32750 flanges as standard and making UNS S32760 flanges to project-specific material needs.

Types of Super Duplex UNS S32750 / S32760 Flanges

Solitaire Overseas supplies a comprehensive range of Super Duplex flanges designed for severe service conditions:

Weld Neck Flanges (WNRF): Features a long tapered hub for butt welding to the pipe. Ideal for high-pressure and high-temperature applications.
Slip-On Flanges (SORF): Slips over the pipe and is fillet welded. Easier to align but lower fatigue strength than weld necks.
Blind Flanges (BLRF): Solid plates used to seal the end of a piping system or vessel opening.
Socket Weld Flanges (SWRF): Used for smaller bore high-pressure piping; the pipe is inserted into a socket and fillet welded.
Threaded Flanges: Connects to the pipe without welding; used in specific hazardous areas where welding is dangerous.
Lap Joint Flanges: Used with Stub Ends; the flange rotates freely for easy alignment of bolt holes

ASTM A182 Super Duplex Steel Slip On Flanges

ASTM A182 Super Duplex Steel Socket Weld Flanges

ASTM A182 Super Duplex Steel Blind Flanges

ASTM A182 Super Duplex Steel Weld Neck Flanges

ASTM A182 Super Duplex Steel Threaded / Screwed Flanges

ASTM A182 Super Duplex Steel Lap Joint Flanges

ASTM A182 Super Duplex Steel Long Weld Neck Flanges

ASTM A182 Super Duplex Steel Spectacle Blind Flanges

ASTM A182 Super Duplex Steel Plate Flanges

ASTM A182 Super Duplex Steel Ring Type Joint Flanges

ASTM A182 Super Duplex Steel Tongue & Groove Flanges

ASTM A182 Super Duplex Steel Reducing Flanges

Types of Super Duplex Steel Flanges & Typical Range

Flange Type	Nominal Size Range (NPS)	Pressure Class	Remarks
Weld Neck (WNRF)	½" – 48"	150# – 2500#	Butt weld connection; highest structural integrity
Slip-On (SORF)	½" – 24"	150# – 1500#	Double fillet weld; cost-effective installation
Blind (BLRF)	½" – 48"	150# – 2500#	For line termination and pressure testing
Socket Weld (SWRF)	½" – 4"	150# – 1500#	Small bore high-pressure systems
Threaded (NPT/BSP)	½" – 4"	150# – 2500#	No welding required
Lap Joint (L/J)	½" – 24"	150# – 2500#	Used with Stub Ends for easy maintenance
Ring Type Joint (RTJ)	2" – 36"	600# – 2500#	Metal-to-metal seal for extreme pressure

Super Duplex Steel UNS S32750 / S32760 Chemical Composition

The exceptional corrosion resistance of Super Duplex stainless steels is directly related to their chemical composition. High chromium and molybdenum contents, together with nitrogen additions, deliver a high Pitting Resistance Equivalent Number (PREN >40) and strong resistance to localized attack.

Chemical Composition of Super Duplex (Typical, wt %)

Grade	ASTM Spec	C	Mn	Si	P	S	Cr	Ni	Mo	N	Fe
S32750	F53	≤0.030	≤1.20	≤0.80	≤0.035	≤0.020	24.0-26.0	6.0-8.0	3.0-5.0	0.24-0.32	Bal
S32760	F55	≤0.030	≤1.00	≤1.00	≤0.030	≤0.010	24.0-26.0	6.0-8.0	3.0-4.0	0.20-0.30	Bal

Mechanical Properties of Super Duplex UNS S32750 / S32760 Flanges

Super Duplex S32750 / S32760 flanges offer mechanical properties significantly higher than common austenitic grades such as 304L and 316L. This high strength allows for higher pressure ratings or lighter flange designs in critical systems.

Mechanical Properties (Typical)

Grade	Density (g/cm³)	Tensile Strength (min)	Yield Strength 0.2% Proof (min)	Elongation (min)	Melting Point
S32750 (F53)	7.8	800 MPa	550 MPa	15%	≈ 1350°C
S32760 (F55)	7.8	> 750 – 800 MPa	> 550 MPa	25%	≈ 1350°C

Super Duplex 2507 Equivalent Grades (UNS S32750 / S32760)

Super Duplex 2507 is referenced under different designations in various standards. A clear grade equivalence table helps avoid mis-specification and supports global sourcing

Equivalent Grades of Super Duplex Stainless Steel

Grade	UNS	ASTM Forging Spec	Werkstoff Nr.	EN / DIN	Common Trade Name
Super Duplex 2507	S32750	A182 F53	1.4410	X2CrNiMoN25-7-4	SAF 2507®
Super Duplex S32760	S32760	A182 F55	1.4501	X2CrNiMoCuWN25-7-4	ZERON® 100

Major Characteristics and Advantages of Super Duplex UNS S32750 / 2507 Flanges

The use of Super Duplex flanges from Solitaire Overseas offers significant technical and commercial benefits:

Excellent Corrosion Protection: Corrosion-resistance to pitting and crevice is obtained with a large amount of chromium, molybdenum and nitrogen to make it excellent in seawater, brines and chloride-containing process streams.
Very High Strength: The yield strength is twice in comparison to 304/316 stainless steel. This ensures that high pressure containment and to a long duration of sealing faces even in cases of extreme bolt loads are achieved.
Stress Corrosion Cracking (SCC) Resistance: Duplex microstructure is highly resistant to chloride SCC particularly at high-temperature when the normal austenitic flanges would have failed.
Full Traceability: We have EN 10204 3.1 test certificates and third party inspection reports and full documentation package to achieve the stringent QA/QC standards.

ASTM A182 s32750Super Duplex Flange Applications and Industries

ASTM A182 S32750/S32760 Super Duplex flanges are widely used in:

Offshore and Onshore Oil & Gas
Desalination & Seawater Handling
Petrochemical Processing
Power Generation
Marine & Shipbuilding

Super Duplex Steel Flanges UNS S32760 – Countries We Export

Solitaire Overseas is a trusted international supplier of high performance piping components. We export Super Duplex UNS S32750 / S32760 flanges to our clients worldwide for new projects, shutdowns, and MRO requirements. Our export division takes care of export-worthy packaging and all the documentation required (MTC 3.1, Certificate of Origin, etc.).

Region	Example Countries	Typical Industries Served
Asia	India, Thailand, Singapore, Malaysia, Indonesia, Vietnam, South Korea	Refineries, Petrochemicals, Power, Desalination, Shipyards
Middle East	UAE, Saudi Arabia, Oman, Qatar, Kuwait, Bahrain, Iraq	Oil & Gas, Offshore Platforms, Desalination Plants
Europe	UK, Germany, Italy, France, Spain, Netherlands, Norway	Chemical Plants, Offshore Wind, Marine, Power
Africa	South Africa, Ghana, Egypt, Nigeria, Angola	Oil & Gas pipelines, Mining, Infrastructure
Americas	USA, Brazil, Mexico, Chile, Colombia, Canada	Offshore Oil & Gas, Mining Slurry Systems
Oceania	Australia, New Zealand	LNG, Offshore Drilling, Mining, Power

Dimensions of Super Duplex UNS S32750 Flanges

The table below provides a detailed Dimensions Chart for the flanges across various pipe sizes, with measurements for outer diameter (O), thickness (T), bolt hole details, and other critical dimensions.

Nom. Pipe Size	O	T	R	X	No./Dia. of Holes	Bolt Circle Dia.	L2	H	B2	L	B	r	L3	B3	D
1/2	3.5	0.44	1.38	1.19	4-0.62	2.38	1.88	0.84	0.62	0.62	0.88	0.12	0.62	0.9	0.38
3/4	3.88	0.5	1.69	1.5	4-0.62	2.75	2.06	1.05	0.82	0.62	1.09	0.12	0.62	1.11	0.44
1	4.25	0.56	2	1.94	4-0.62	3.12	2.19	1.32	1.05	0.69	1.36	0.12	0.69	1.38	0.5
1-1/4	4.62	0.62	2.5	2.31	4-0.62	3.5	2.25	1.66	1.38	0.81	1.7	0.19	0.81	1.72	0.56
1-1/2	5	0.68	2.88	2.56	4-0.62	3.88	2.44	1.9	1.61	0.88	1.95	0.25	0.88	1.97	0.62
2	6	0.75	3.62	3.06	4-0.75	4.75	2.5	2.38	2.07	1	2.44	0.31	1	2.46	0.69
2-1/2	7	0.88	4.12	3.56	4-0.75	5.5	2.75	2.88	2.47	1.12	2.94	0.31	1.12	2.97	0.75
3	7.5	0.94	5	4.25	4-0.75	6	2.75	3.5	3.07	1.19	3.57	0.38	1.19	3.6	0.81
3-1/2	8.5	0.94	5.5	4.81	8-0.75	7	2.81	4	3.55	1.25	4.07	0.38	1.25	4.1	0.88
4	9	0.94	6.19	5.31	8-0.75	7.5	3	4.5	4.03	1.31	4.57	0.44	1.31	4.6	0.94
5	10	0.94	7.31	6.44	8-0.88	8.5	3.5	5.56	5.05	1.44	5.66	0.44	1.44	5.69	0.94
6	11	1	8.5	7.56	8-0.88	9.5	3.5	6.63	6.07	1.56	6.72	0.5	1.56	6.75	1.06
8	13.5	1.12	10.62	9.69	8-0.88	11.75	4	8.63	7.98	1.75	8.72	0.5	1.75	8.75	1.25
10	16	1.19	12.75	12	12-1.00	14.25	4	10.75	10.02	1.94	10.88	0.5	1.94	10.92	1.31
12	19	1.25	15	14.38	12-1.00	17	4.5	12.75	12	2.19	12.88	0.5	2.19	12.92	1.56
14	21	1.38	16.25	15.75	12-1.12	18.75	5	14	13.25	2.25	14.14	0.5	3.12	14.18	1.63
16	23.5	1.44	18.5	18	16-1.12	21.25	5	16	15.25	2.5	16.16	0.5	3.44	16.19	1.75
18	25	1.56	21	19.88	16-1.25	22.75	5.5	18	17.25	2.69	18.18	0.5	3.81	18.2	1.94
20	27.5	1.69	23	22	20-1.25	25	5.69	20	19.25	2.88	20.2	0.5	4.06	20.25	2.13
22	29.5	1.81	25.25	24.25	20-1.38	27.25	5.88	22	21.25	3.13	22.22	0.5	4.25	22.25	2.38
24	32	1.88	27.25	26.12	20-1.38	29.5	6	24	23.25	3.25	24.25	0.5	4.38	24.25	2.5

Weight Chart Of Super Duplex UNS S32750/ F53 Flanges

The weight chart provides dimensional information for various flange sizes and pressure classes.

Normal Sizes (inch/mm)	Dimension	Class 125/150		Class 300		Class 400		Class 600		Class 900		Class 1500		Class 2500
inch	mm	inch	mm	inch	mm	inch	mm	inch	mm	inch	mm	inch	mm
1/2	A	3 1/2	88.9	3 3/4	95.2	3 3/4	95.2	3 3/4	95.2	4 3/4	121	4 3/4	121	5 1/4
	b	7/16	11.1	9/16	14.3	9/16	14.3	9/16	14.3	7/8	22.2	7/8	22.2	1 3/16
	D2	1 3/8	34.9	1 3/8	34.9	1 3/8	34.9	1 3/8	34.9	1 3/8	34.9	1 3/8	34.9	1 3/8
	D1	2 3/8	60.3	2 5/8	66.7	2 5/8	66.7	2 5/8	66.7	3 1/4	82.6	3 1/4	82.6	3 1/2
3/4	A	3 7/8	98.4	4 5/8	117.5	4 5/8	117.5	4 5/8	117.5	5 1/8	130	5 1/8	130	5 1/2
	b	1/2	12.7	5/8	15.9	5/8	15.9	5/8	15.9	1	25.4	1	25.4	1 1/4
	D2	1 11/16	42.9	1 11/16	42.9	1 11/16	42.9	1 11/16	42.9	1 11/16	42.9	1 11/16	42.9	1 11/16
	D1	2 3/4	69.8	3 1/4	82.5	3 1/4	82.5	3 1/4	82.5	3 1/2	88.9	3 1/2	88.9	3 3/4
1	A	4 1/4	108	4 7/8	123.8	4 7/8	123.8	4 7/8	123.8	5 7/8	149.2	5 7/8	149.2	6 1/4
	b	9/16	14.3	11/16	17.5	11/16	17.5	11/16	17.5	1 1/8	28.6	1 1/8	28.6	1 3/8
	D2	2	50.8	2	50.8	2	50.8	2	50.8	2	50.8	2	50.8	2
	D1	3 1/8	79.4	3 1/2	88.9	3 1/2	88.9	3 1/2	88.9	4	102	4	102	4 1/4
1 1/4	A	4 5/8	117.5	5 1/4	133.4	5 1/4	133.4	5 1/4	133.4	6 1/4	159	6 1/4	159	7 1/4
	b	5/8	15.9	3/4	19	13/16	20.6	13/16	20.6	1 1/8	28.6	1 1/8	28.6	1 1/2
	D2	2 1/2	63.5	2 1/2	63.5	2 1/2	63.5	2 1/2	63.5	2 1/2	63.5	2 1/2	63.5	2 1/2
	D1	3 1/2	88.9	3 7/8	98.4	3 7/8	98.4	3 7/8	98.4	4 3/8	111	4 3/8	111	5 1/8
1 1/2	A	5	127	6 1/8	155.6	6 1/8	155.6	6 1/8	155.6	7	177.8	7	177.8	8
	b	11/16	17.5	13/16	20.6	7/8	22.2	7/8	22.2	1 1/4	31.8	1 1/4	31.8	1 3/4
	D2	2 7/8	73	2 7/8	73	2 7/8	73	2 7/8	73	2 7/8	73	2 7/8	73	2 7/8
	D1	3 7/8	98.4	4 1/2	114	4 1/2	114	4 1/2	114	4 7/8	124	4 7/8	124	5 3/4
2	A	6	152.4	6 1/2	165.1	6 1/2	165.1	6 1/2	165.1	8 1/2	215.9	8 1/2	215.9	9 1/4
	b	3/4	19	7/8	22.2	1	25.4	1	25.4	1 1/2	38.1	1 1/2	38.1	2
	D2	3 5/8	92.1	3 5/8	92.1	3 5/8	92.1	3 5/8	92.1	3 5/8	92.1	3 5/8	92.1	3 5/8
	D1	4 3/4	121	5	127	5	127	5	127	6 1/2	165.1	6 1/2	165.1	6 3/4
2 1/2	A	7	177.8	7 1/2	190.5	7 1/2	190.5	7 1/2	190.5	9 5/8	244	9 5/8	244	10 1/2
	b	7/8	22.2	1	25.4	1 1/8	28.6	1 1/8	28.6	1 5/8	41.3	1 5/8	41.3	2 1/4
	D2	4 1/8	104.8	4 1/8	104.8	4 1/8	104.8	4 1/8	104.8	4 1/8	105	4 1/8	105	4 1/8
	D1	5 1/2	139.7	5 7/8	149.2	5 7/8	149.2	5 7/8	149.2	7 1/2	190.5	7 1/2	190.5	7 3/4

Frequently Asked Questions: Super Duplex UNS S32750 / S32760 Flanges

The difference between S32750 (F53) and S32760 (F55) flanges?

They are both Super Duplex grades that have a similar microstructure. The most common offshore and desalination applications are fertilized with UNS S32750 (F53) which is the standard Super Duplex grade (2507). UNS S32760 (F55) is a material with additions of Tungsten and Copper, which provides a slight increase in PREN valuables, and possibly, increases performance in particularly acidic/sour conditions. S32760 is commonly selected to suit historical requirements such as ZERON(r) 100.

What are the criteria of Super Duplex flanges?

Super duplex flanges are produced with the material standard of ASTM A182 / ASME SA182. Flange dimensions to 24 inch tend to conform to ASME B16.5, but larger flange dimensions (26 -60 inch) are typically based on ASME B16.47 (Series A or B). We also supply to EN 1092-1 as well as API 6A standards.

Will these flanges work in sea water?

Yes, absolutely. UNS S32750 flanges are engineered to work in sea water with a PREN of more than 40. They have resistance to pitting and crevice corrosion which would quickly ruin the Grade 316 stainless steel in the identical environment.

What are some of the flange face types you supply?

We are providing all the common face variations such as Raised Face (RF), Flat Face (FF) and Ring Type Joint (RTJ). RTJ flanges are also typically used in high-pressure Super Duplex applications (Class 900# to 2500#), to guarantee a high-integrity metal-to-metal seal.