Stainless Steel 310S Flanges

Stainless Steel 310S Flanges are pipe connection components manufactured from UNS S31008, a high-chromium, high-nickel austenitic stainless steel with a carbon content capped at 0.08%. The only real difference between 310 and 310S is the “S” designation, meaning lower carbon that minimises carbide precipitation at grain boundaries, making 310S better for welded assemblies in increased temperature service. Stainless Steel 310S Flanges have the same excellent oxidation and scaling resistance as 310, but with higher weldability and less danger of sensitisation.

These flanges are available across all standard face types, pressure classes, and flange forms. UNS S31008 Flanges are specified wherever high-temperature piping systems are welded without post-weld heat treatment and wherever carburisation, scaling, or sulphidation resistance is a design requirement. Their combination of elevated-temperature strength and reliable weld performance makes them the preferred choice over standard 310 in most fabricated process systems.

Price of Stainless Steel 310S Flanges

Stainless Steel 310S Flanges Competitive Price structures for procurement budgets optimisation. These industrial-grade components are designed for heat situations, providing higher oxidation resistance, extended durability, and leak-proof integration into the piping network.

Price Per Unit / Kg

Stainless Steel 310S Flanges are priced between ₹650 and ₹2,400 per kg in the Indian market. International pricing tracks LME nickel rates. 310S contains 19–22% nickel, making it sensitive to nickel market movements. Stainless Steel 310S Flanges price is comparable to standard 310 in most markets; the carbon limit difference does not materially affect raw material cost.

Factors Affecting Price

High chromium (24–26%) and nickel (19–22%) content are the primary raw material drivers. Pressure class, flange type, size, and certification level all affect final pricing. Stainless Steel 310S Flanges suppliers offering ASTM-certified, heat-traceable material at a premium over uncertified stock.

Types of Stainless Steel 310S Flanges

Explore the high-temperature range of 310S components designed for exceptional performance in heat-intensive industrial piping.

Stainless Steel 310S Weld Neck Flanges (WN)
Stainless Steel 310S Slip-On Flanges (SO)
Stainless Steel 310S Blind Flanges (BL)
Stainless Steel 310S Socket Weld Flanges (SW)
Stainless Steel 310S Threaded Flanges (TH)
Stainless Steel 310S Lap Joint Flanges (LJ)
Stainless Steel 310S Long Weld Neck Flanges (LWN)
Stainless Steel 310S Orifice Flanges
Stainless Steel 310S Reducing Flanges
Stainless Steel 310S Spectacle Blind Flanges
Stainless Steel 310S Ring Type Joint (RTJ) Flanges

Specifications of Stainless Steel 310S Flanges

Below is the specification for Stainless Steel 310S Flanges, including size, standard, and pressure class.

Feature	Details
Standard	ASTM A182/ ASME SA 182
Size Range	1/2" (15 NB) to 48" (1200 NB); DN10 ~ DN5000
Pressure Ratings (ANSI)	Class 150, 300, 600, 900, 1500, and 2500 LBS
Production Technique	Forged, heat-treated, and precision-machined
Bore Sizes	NPS ≤ 10 for the largest bore diameter sizes
Testing & Certification	EN 10204/3.1B, Raw Material Certificates, 100% Radiography, Third Party Inspection

Chemical Properties of Stainless Steel 310S Flanges

The chemical composition of Stainless Steel 310S Flanges, including its proportions, is listed in the table below.

Grade	C	Mn	Si	P	S	Cr	Ni	N
310S Min	—	—	—	—	—	24.0	19.0	—
310S Max	0.08	2.0	1.50	0.045	0.030	26.0	22.0	—

Mechanical Properties of Stainless Steel 310S Flanges

The mechanical properties of Stainless Steel 310S Flanges, including tensile strength, yield strength, and elongation, are listed below.

Property	Value
Tensile Strength	515 MPa min
Yield Strength (0.2% Offset)	205 MPa min
Elongation (% in 50 mm)	40% min
Hardness (Brinell)	217 HB max

Physical Properties of Stainless Steel 310S Flanges

The physical properties of Stainless Steel 310S Flanges are listed in the table below, along with density and thermal conductivity.

Grade	Density (kg/m³)	Elastic Modulus (GPa)	Mean Co-eff of Thermal Expansion (µm/m/°C) 0–100°C	Thermal Conductivity (W/m.K) at 100°C	Specific Heat (J/kg.K)	Elec Resistivity (nΩ.m)
310S	7900	200	15.9	14.2	500	780

Dimension Chart of Stainless Steel 310S Flanges

Please refer to the chart given below for SS 310S flange dimensions. High-temperature 310/310S pipe system measurements give the precision.

NPS	Outside Dia (O)	Thickness (T)	Raised Face (R)	Hub Base (X)	Bolt Circle	No. / Dia of Holes	WN Length (L)	Bore (B)
1/2"	3.50	0.44	1.38	1.19	2.38	4 / 0.62	1.88	0.62
3/4"	3.88	0.50	1.69	1.50	2.75	4 / 0.62	2.06	0.82
1"	4.25	0.56	2.00	1.94	3.12	4 / 0.62	2.19	1.05
1-1/4"	4.62	0.62	2.50	2.31	3.50	4 / 0.62	2.25	1.38
1-1/2"	5.00	0.68	2.88	2.56	3.88	4 / 0.62	2.44	1.61
2"	6.00	0.75	3.62	3.06	4.75	4 / 0.75	2.50	2.07
2-1/2"	7.00	0.88	4.12	3.56	5.50	4 / 0.75	2.75	2.47
3"	7.50	0.94	5.00	4.25	6.00	4 / 0.75	2.75	3.07
4"	9.00	0.94	6.19	5.31	7.50	8 / 0.75	3.00	4.03
6"	11.00	1.00	8.50	7.56	9.50	8 / 0.88	3.50	6.07
8"	13.50	1.12	10.62	9.69	11.75	8 / 0.88	4.00	7.98
10"	16.00	1.19	12.75	12.00	14.25	12 / 1.00	4.00	10.02
12"	19.00	1.25	15.00	14.38	17.00	12 / 1.00	4.50	12.00
14"	21.00	1.38	16.25	15.75	18.75	12 / 1.12	5.00	13.25
16"	23.50	1.44	18.50	18.00	21.25	16 / 1.12	5.00	15.25
20"	27.50	1.69	23.00	22.00	25.00	20 / 1.25	5.69	19.25
24"	32.00	1.88	27.25

Dimensions per ASME B16.5 Class 150. Confirm dimensions for other pressure classes with your supplier.

Size Chart of Stainless Steel 310S Flanges

See the comprehensive Size Chart of Stainless Steel 310S Flanges below for detailed dimensions and pressure ratings.

Type	Size Range (NB)	Pressure Class	Standard
Weld Neck	1/2" – 24"	Class 150 – 2500	ASME B16.5
Slip-On	1/2" – 24"	Class 150 – 600	ASME B16.5
Blind	1/2" – 24"	Class 150 – 2500	ASME B16.5
Socket Weld	1/2" – 3"	Class 150 – 2500	ASME B16.5
Threaded	1/2" – 4"	Class 150 – 2500	ASME B16.5
Lap Joint	1/2" – 24"	Class 150 – 600	ASME B16.5
Large Diameter	26" – 60"	Class 75 – 900	ASME B16.47

Pressure Rating Chart of Stainless Steel 310S Flanges

The detailed information about the maximum allowed working pressure for 310S flanges at common operating temperatures is shown in the chart below.

Pressure Class	–29 to 38°C	100°C	200°C	300°C
Class 150	19.0	16.0	13.8	10.2
Class 300	49.6	41.9	35.8	31.6
Class 600	99.3	83.7	71.7	63.3
Class 900	148.9	125.6	107.5	94.9
Class 1500	248.2	209.3	179.2	158.2
Class 2500	413.7	348.9	298.6

Pressure ratings per ASME B16.5 for Group 2.2 (SS 310S). Always verify with the relevant ASME B16.5 table for your exact service temperature.

Key Features of Stainless Steel 310S Flanges

Discover more about the specialised characteristics of stainless steel 310S flanges by following the pointers:

Reduced Carbon Content
Oxidation Resistance
High-Temperature Stability
Superior Weldability
No PWHT Required
Standard Facing Options
Non-Magnetic Properties
Code Compliance

Applications of Stainless Steel 310S Flanges

Explore the critical high-temperature environments where these components are primarily utilised:

Industrial Furnaces
Petrochemical Reformers
Kilns & Incinerators
Power Generation
Cement Production
High-Heat Chemical Processing
Heat Exchanger Connections
Boilers & Superheaters
Thermal Oxidisers

How to Choose the Right Stainless Steel 310S Flanges Supplier?

Before placing the procurement order, please consider the following points to make your purchase best for your project.

Supplier Selection Criteria

Verify that the supplier provides mill test certificates with full heat and lot traceability confirming UNS S31008 composition. SS 310S and standard 310 share the same Werkstoff Nr (1.4845) but have different carbon limits. Check the carbon value on the MTC before accepting material. Always request EN 10204 3.1 as a minimum; EN 10204 3.2 is required for pressure equipment and ASME pressure systems.

Technical Considerations

Confirm flange standard and pressure class before ordering. ASME B16.5 covers up to 24" NB; ASME B16.47 covers 26" and above. For high-temperature welded systems, all the linked components, pipe, fittings, and UNS S31008 Flanges should be of the same confirmed grade to avoid composition mismatch at the welds. Ensure the use of the ASTM A182 F310S certification for ASME pressure systems, not generic plate or bar-converted stock.

Quality & Certification Check

Prioritise Stainless Steel 310S flange suppliers with ISO 9001:2015 certification and third-party inspection capability from SGS, BV, TUV, or Lloyds. For European projects, confirm EN 1092-1 and Werkstoff Nr. 1.4845 documentation is available. All flanges must be supplied in the solution-annealed condition; confirm heat treatment records are part of every documentation package.

Procurement Tips for Bulk Orders

Simplify MTC management and improve price on this high-alloy grade by consolidating flange types, sizes, and pressure classes with one single 310S supplier. A vendor-qualified supplier eliminates the overhead of repeatedly verifying the quality of the supplier for continuous project supplies. Compare MTC and quotations of two to three Stainless Steel 310S Flanges vendors for new procurement to verify chemistry and benchmark the current market price.