Stainless Steel 904L Flanges Manufacturer & Supplier
Midland Alloys Inc. is India’s trusted manufacturer and global supplier of Stainless Steel 904L Flanges, known for delivering exceptional quality with precision. Stainless Steel 904L is a high-alloy, low-carbon austenitic stainless steel containing approximately 23% nickel, 19% chromium, 4% molybdenum, copper, and trace amounts of elements like manganese, silicon, phosphorus, and sulfur. This unique combination greatly improves its resistance to aggressive chemicals and highly reducing acids. Being resistant to corrosion from sulfuric acid, seawater and chloride-bearing environments, SS 904L Flanges ensure exceptional performance in pitting, crevice corrosion, and stress corrosion cracking. In harsh chemical and atmospheric conditions, these flanges offer exceptional strength, weldability, and fabrication capabilities. Their dependability and flexibility make it popular for various industries. They are available in seamless and welded types, including WNRF, SORF, BLRF, threaded, and lap joint flanges. Midland Alloys Inc. delivers high-quality Stainless Steel 904L Flanges at competitive prices to meet every industrial need.
Stainless Steel 904L Flanges Overview
SS 904L Flanges are strong, low-carbon, high-alloy flanges designed for demanding applications that include corrosive media, high temperatures and strong acids. These flanges are strong and long-lasting, made to withstand harsh chemical plants, maritime conditions, and systems that contain chloride. Available in different forms like WNRF, SORF, BLRF, threaded and lap joint, these flanges find application in different piping arrangements and designs. UNS N08904, a premium stainless steel alloy, that offer exceptional resistance to harsh chemicals while retaining its mechanical strength under high stress conditions. Perfect for integrated plumbing systems, SS 904L flanges are designed for easy installation and seamless compatibility with other components. Manufactured in accordance with international standards such as ANSI B16.5 and ASME SA182, these flanges deliver reliable and long-lasting performance across a wide range of industries.
Stainless Steel 904L Flanges Benefits
Stainless Steel 904L Flanges offer a combination of performance, strength, and reliability, making them a preferred choice across critical sectors.
- Outstanding resilience to corrosive conditions, such as seawater and acids
- Strong mechanical properties for demanding industrial uses
- Superior weldability ensures joint integrity and ease of fabrication.
- Retains strength under thermal stress at high temperatures.
- Maintains accurate dimensions when subjected to mechanical stress.
- Prevents product contamination by providing a smooth surface finish.
- Meets complete adherence with global safety, and quality requirements
- Reduces long-term operating expenses due to its low maintenance requirements.
Stainless Steel 904L Flanges Specification
Stainless steel 904L flanges are manufactured in seamless and welded forms to satisfy international standards such as ASTM A182, ANSI B16.5, and ASME SA182. -SS 904L Flanges come in multiple pressure classes, and sizes to cater to the needs of different industries.
1/2" (15 NB) to 48" (1200NB)
ASTM A182 / ASME SA182
ANSI/ASME B16.5, B 16.47 Series A & B, B16.48, BS4504, BS 10, EN-1092, DIN, etc.
Threaded / Screwed / Forged / Plate
150#, 300#, 600#, 900#, 1500#, 2500#, PN6, PN10, PN16, PN25, PN40, PN64 etc.
Flate Face (FF), Raised Face (RF), Ring Type Joint (RTJ)
Forging, Rolling, Casting
FNPT, NPT, BSPT, MNPT, BSPP
Types Of Stainless Steel 904L Flanges
Midland Alloys provides WNRF, SORF, BLRF, threaded, and other joint types to meet various piping connection requirements.
Manufacturing Types
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SORF (Slip-On Raised Face)Slides over the pipe and gets welded for easy installation in low-pressure systems.
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BLRF (Blind Raised Face)Closes off pipe ends; used for testing or sealing flow in a system.
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SWRF (Socket Weld Raised Face)Pipe fits into a recessed area and is welded around the edge. Ideal for small-bore, high-pressure lines.
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WNRF (Weld Neck Raised Face)Has a long, tapered hub and welds to the pipe for strong, leak-proof joints under high pressure.
Face Forms
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Raised Face (RF)The most common type has a raised surface that improves gasket sealing in medium to high pressure.
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Ring Type Joint (RTJ)Uses a metal ring for sealing and works well in high-pressure, high-temperature services.
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Flat Face (FF)Flat surface flange used with cast iron or low-pressure piping where full face gasket is needed.
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Lap-Joint Face (LJF)Used with stub ends and are easy to align and install. Good for systems that need frequent dismantling.
Technical Details & Delivery Condition
Equivalent to UNS N08904 and DIN 1.4539, SS 904L Flanges align with global grade standards for reliable international usage.
| STANDARD | WERKSTOFF NR. | UNS | JIS | BS | KS | AFNOR | EN |
| SS 904L | 1.4539 | N08904 | SUS 904L | 904S13 | STS 317J5 | Z2 NCDU 25-20 | X1NiCrMoCu25-20-5 |
A high performance alloy which includes 23% nickel, 19% chromium, 4% molybdenum, copper and trace elements to improve corrosion resistance are used to make these flanges.
| Grade | C | Mn | Si | P | S | Cr | Mo | Ni | Cu |
| SS 904L | 0.020 max | 2 max | 1.00 max | 0.040 max | 0.030 max | 19.00 – 23.00 | 4.00 – 5.00 max | 23.00 – 28.00 | 1.00 – 2.00 |
The exceptional mechanical qualities of SS 904L Flanges, such as their high tensile, yield, and elongation strengths, ensure structural integrity even under the most demanding loads.
| Density | Melting Point | Tensile Strength | Yield Strength (0.2%Offset) | Elongation |
| 7.95 g/cm3 | 1350 °C (2460 °F) | Psi – 71000 , MPa – 490 | Psi – 32000 , MPa – 220 | 35 % |
These flanges are produced in compliance with ANSI B16.5, which covers standard dimensional tolerances, pressure classes, and size ranges.
| Standard | Class | Diameter | Bolt Circle Diameter | Number of Bolts | Bolt Size | Diameter of Bolt Hole |
|---|---|---|---|---|---|---|
| AS4087 | PN14 | 95 | 67 | 4 | M12 | 14 |
| AS 2129 Flange | Table C | 95 | 67 | 4 | 13 | 14 |
| Table D | 95 | 67 | 4 | 13 | 14 | |
| Table E | 95 | 67 | 4 | 13 | 14 | |
| Table F | 95 | 67 | 4 | 13 | 14 | |
| Table H | 114 | 83 | 4 | 16 | 17 | |
| Table J | 114 | 83 | 4 | 16 | 17 | |
| ANSI B16.5 | ANSI 150 | 89 | 60 | 4 | 13 | 16 |
| ANSI 300 | 95 | 67 | 4 | 13 | 16 | |
| ANSI 600 | 95 | 67 | 4 | 13 | 16 | |
| ANSI 900 | 121 | 83 | 4 | 19 | 22 | |
| ANSI 1500 | 121 | 83 | 4 | 19 | 22 | |
| ISO 7005 (DIN) Flange | PN6 | 80 | 55 | 4 | M10 | 11 |
| PN10 | 95 | 65 | 4 | M12 | 14 | |
| PN16 | 95 | 65 | 4 | M12 | 14 | |
| PN20 | 90 | 60.5 | 4 | M14 | 16 | |
| PN25 | 95 | 65 | 4 | M12 | 14 | |
| PN40 | 95 | 65 | 4 | M12 | 14 |
Flange weights vary based on size, thickness, and pressure class—use our standard chart for accurate shipping and design estimates.
| Pipe Normal Diam. | O.D. Flange | Thk. Of Flange Min | Diam. of Hub | Diameter of Raised Face | Length Hub.Y | Thread Length | Diam. of Bolt Circle | Diam. of Bolt Holes | Number of Bolts | Diam. of Bolts (inch) | KG | LB | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| inch | dn | O | C | X | G | Y | T | BC | BH | BN | BD | ||
| 1/2″ | 15 | 89.00 | 11.20 | 30.20 | 35.10 | 15.70 | 15.70 | 60.50 | 15.80 | 4 | 1/2″ | 0.4 | 0.9 |
| 3/4″ | 20 | 98.50 | 12.70 | 38.10 | 42.90 | 15.70 | 15.70 | 69.90 | 15.80 | 4 | 1/2″ | 0.7 | 1.5 |
| 1″ | 25 | 108.00 | 14.20 | 49.30 | 50.80 | 17.50 | 17.50 | 79.30 | 15.80 | 4 | 1/2″ | 0.8 | 1.8 |
| 1-1/4″ | 32 | 117.50 | 15.70 | 58.70 | 63.50 | 20.60 | 20.60 | 88.90 | 15.80 | 4 | 1/2″ | 1.2 | 2.6 |
| 1-1/2″ | 40 | 127.00 | 17.50 | 65.00 | 73.20 | 22.40 | 22.40 | 98.60 | 15.80 | 4 | 1/2″ | 1.5 | 3.3 |
| 2″ | 50 | 152.50 | 19.10 | 77.70 | 91.90 | 25.40 | 25.40 | 120.70 | 19.10 | 4 | 5/8″ | 2.3 | 5.1 |
| 2-1/2″ | 65 | 178.00 | 22.40 | 90.40 | 104.60 | 28.40 | 28.40 | 139.70 | 19.10 | 4 | 5/8″ | 3.7 | 8.1 |
| 3″ | 80 | 190.50 | 23.90 | 108.00 | 127.00 | 30.20 | 30.20 | 152.40 | 19.10 | 4 | 5/8″ | 4.1 | 9 |
| 3-1/2″ | 90 | 216.00 | 23.90 | 122.20 | 139.70 | 31.80 | 31.80 | 177.80 | 19.10 | 8 | 5/8″ | 5.1 | 11.2 |
| 4″ | 100 | 228.50 | 23.90 | 134.90 | 157.20 | 33.30 | 33.30 | 190.50 | 19.10 | 8 | 5/8″ | 5.9 | 13 |
| 5″ | 125 | 254.00 | 23.90 | 163.60 | 185.70 | 36.60 | 36.60 | 215.90 | 22.40 | 8 | 3/4″ | 7 | 15.4 |
| 6″ | 150 | 279.50 | 25.40 | 192.00 | 215.90 | 39.60 | 39.60 | 241.30 | 22.40 | 8 | 3/4″ | 8.4 | 18.5 |
| 8″ | 200 | 343.00 | 28.40 | 246.10 | 269.70 | 44.50 | 44.50 | 298.50 | 22.40 | 8 | 3/4″ | 13 | 28.6 |
| 10″ | 250 | 406.50 | 30.20 | 304.80 | 323.90 | 49.30 | 49.30 | 362.00 | 25.40 | 12 | 7/8″ | 18 | 39.5 |
| 12″ | 300 | 482.50 | 31.80 | 365.30 | 381.00 | 55.60 | 55.60 | 431.80 | 25.40 | 12 | 7/8″ | 29 | 64 |
| 14″ | 350 | 533.50 | 35.10 | 400.10 | 412.80 | 57.20 | 57.20 | 476.30 | 28.50 | 12 | 1″ | 39 | 86 |
| 16″ | 400 | 597.00 | 36.60 | 457.20 | 469.90 | 63.50 | 63.50 | 539.80 | 28.50 | 16 | 1″ | 47 | 103 |
| 18″ | 450 | 635.00 | 39.60 | 505.00 | 533.40 | 68.30 | 68.30 | 577.90 | 31.80 | 16 | 1 1/8″ | 57 | 126 |
| 20″ | 500 | 698.50 | 42.90 | 558.80 | 584.20 | 73.20 | 73.20 | 635.00 | 31.80 | 20 | 1 1/8″ | 76 | 167 |
| 24″ | 600 | 813.00 | 47.80 | 663.40 | 692.20 | 82.60 | 82.60 | 749.30 | 35.10 | 20 | 1 1/4″ | 97 | 214 |
904L flanges can be integrated, with pressure gauges to monitor system pressure, particularly in corrosive, or high performance applications.
| ANSI/ASME B16.34 | PRESSURE RATING CHART | ||||||
| Temperature °F | 150# | 300# | 400# | 600# | 900# | 1500# | 2500# |
| -20 to 100 | 275 | 720 | 960 | 1440 | 2160 | 3600 | 6000 |
| 200 | 230 | 600 | 800 | 1200 | 1800 | 3000 | 5000 |
| 300 | 205 | 540 | 720 | 1080 | 1620 | 2700 | 4500 |
| 400 | 190 | 495 | 660 | 995 | 1490 | 2485 | 4140 |
| 500 | 170 | 465 | 620 | 930 | 1395 | 2330 | 3880 |
| 600 | 140 | 435 | 580 | 875 | 1310 | 2185 | 3640 |
| 650 | 125 | 430 | 575 | 860 | 1290 | 2150 | 3580 |
| 700 | 110 | 425 | 565 | 850 | 1275 | 2125 | 3540 |
| 750 | 95 | 415 | 555 | 830 | 1245 | 2075 | 3460 |
| 800 | 80 | 405 | 540 | 805 | 1210 | 2015 | 3360 |
| 850 | 65 | 395 | 530 | 790 | 1190 | 1980 | 3300 |
| 900 | 50 | 390 | 520 | 780 | 1165 | 1945 | 3240 |
| 950 | 35 | 380 | 510 | 765 | 1145 | 1910 | 3180 |
| 1000 | 20 | 320 | 430 | 640 | 965 | 1605 | 2675 |
| 1050 | 20 | 310 | 410 | 615 | 925 | 1545 | 2570 |
| 1100 | 20 | 255 | 345 | 515 | 770 | 1285 | 2145 |
| 1150 | 20 | 200 | 265 | 400 | 595 | 995 | 1655 |
| 1200 | 20 | 155 | 205 | 310 | 465 | 770 | 1285 |
| 1250 | 20 | 115 | 150 | 225 | 340 | 565 | 945 |
| 1300 | 20 | 85 | 115 | 170 | 255 | 430 | 715 |
| 1350 | 20 | 60 | 80 | 125 | 185 | 310 | 515 |
| 1400 | 20 | 50 | 65 | 95 | 145 | 240 | 400 |
| 1450 | 15 | 35 | 45 | 70 | 105 | 170 | 285 |
| 1500 | 10 | 25 | 35 | 55 | 80 | 135 | 230 |
| NPS (Nominal Pipe Size) | Outside Diameter (OD) mm | Bolt Circle Diameter (BCD) mm | Number of Bolts | Bolt Size | Flange Thickness (mm) | Raised Face Diameter (mm) |
|---|---|---|---|---|---|---|
| 1/2″ | 90 | 65 | 4 | 1/2″ | 14 | 65 |
| 3/4″ | 105 | 80 | 4 | 1/2″ | 14 | 80 |
| 1″ | 120 | 95 | 4 | 5/8″ | 16 | 95 |
| 1 1/2″ | 165 | 125 | 4 | 5/8″ | 18 | 125 |
| 2″ | 180 | 150 | 4 | 3/4″ | 19 | 150 |
| 3″ | 230 | 190 | 6 | 3/4″ | 22 | 190 |
| 4″ | 285 | 250 | 8 | 7/8″ | 24 | 250 |
| 6″ | 340 | 310 | 8 | 1″ | 27 | 310 |
| 8″ | 405 | 370 | 8 | 1 1/8″ | 30 | 370 |
| 10″ | 480 | 445 | 12 | 1 1/8″ | 33 | 445 |
| 12″ | 560 | 520 | 12 | 1 1/4″ | 36 | 520 |
| 14″ | 635 | 585 | 12 | 1 3/8″ | 38 | 585 |
| 16″ | 710 | 650 | 16 | 1 3/8″ | 41 | 650 |
| 18″ | 840 | 760 | 16 | 1 1/2″ | 43 | 760 |
| 20″ | 915 | 825 | 20 | 1 1/2″ | 46 | 825 |
| 24″ | 1065 | 940 | 20 | 1 3/4″ | 50 | 940 |
Stainless Steel Flanges Grades We Offer
Manufacturing Process of Stainless Steel 904L Flanges
Midland Alloys Inc. is one of the leading manufacturers of Stainless Steel 904L Flanges, offering custom sizes, and competitive pricing. These flanges are crafted using high-quality raw materials and advanced manufacturing techniques to meet stringent global standards. The process of making SS 904L flanges begins, with the meticulous selection of premium raw materials, which is then followed by precise cutting. After heating, the material is shaped into the desired flange type. Heat treatment is used after forming in order to improve the internal structure, and mechanical properties. In order to maintain the exact dimensional accuracy, CNC machining is used. To make sure it is free of flaws, each flange goes through rigorous dimensional check, and non destructive testing process. Before delivery, a final comprehensive inspection is carried out to ensure performance, and quality.
Plate
Shear
Press
Inspection
Lathe
Drilling
Cleaning
Flange
Inspection
Analytic
Marking
Packing & Shipping
Stainless Steel 904L Flanges Applications
Stainless Steel 904L Flanges find extensive application in chemical processing plants due to their higher acid resistance and durability. In the pharmaceutical industry, their hygienic characteristics provide contamination-free flow systems. The oil and gas industry depends on them due to their strength and corrosion resistance under high pressure. Food and beverage plants utilize them due to their non-reactive quality and smooth finish. Power generation and heat exchangers utilize these flanges for high-temperature operations with long-term reliability. They are also used in pulp and paper industries, pollution control equipment, and wastewater treatment facilities where high corrosion resistance is essential. Marine engineering, and offshore platforms utilise these flanges for their durability in saltwater environments. Their ability to withstand mechanical stress and chemical exposure makes them essential for critical and safety-sensitive operations across a wide range of sectors.
Our Packing Standards
Stainless Steel 904L Flanges are wrapped with export-grade materials to avoid getting damaged during transport and handling. The packaging methods are HDPE wrapping, shrink wrapping, plastic cap bundling and wooden crates with secure fastening. Details like grade, size, standard, and heat number are precisely marked on each and every package. We ensure worldwide shipping through air, or sea as well as domestic delivery via rail and road. We manage urgent inquiries, large bulk, and project-specific requirements. Custom orders require additional times, but in-stock items are shipped the same day. Invoices, packing lists, test certifications and export documentation are examples of accompanying documents. Additionally, we provide flexible packaging in accordance with customer preferences, or global standards such as GCC and EU regulations.
Why Choose Midland Alloys Inc.
Midland Alloys Inc. is a reputable company in the stainless steel sector, known for high-quality products and dependable customer satisfaction. As a top manufacturer, and supplier, we provide custom sizes and specifications to meet the project requirements at affordable rates.
With a strong global network of supplies, we provide timely delivery of certified goods produced with cutting-edge technology, and high-quality standards. Our wide industry reach, trustworthy certifications and dedication to client satisfaction make us the perfect partner for Stainless Steel 904L Flanges. We stand out by combining technical expertise with customer-centric service, ensuring every order meets the exact expectations of our clients. From offering prompt responses to complex project inquiries to maintaining complete traceability and documentation, we focus on delivering value beyond just the product. Our team of skilled engineers and quality controllers continuously works to innovate, optimise and improve product performance. Whether you’re sourcing for critical infrastructure, offshore platforms, or high-purity applications, Midland Alloys Inc. ensures consistency, integrity, and long-term trust with every flange we deliver.
FAQs
Yes, because of their austenitic structure, and lower carbon content SS 310 and 310S flanges provide outstanding weldability and are appropriate for fabrication procedures like forming and machining.
UNS N08904 is the standard and most reliable grade for Stainless Steel 904L Flanges.
Yes, 904L is more expensive than standard grades due to its high alloy content and superior properties.
