Flanges Manufacturers and Suppliers

Silver Tubes is a prime manufacturer of flanges in India and effectively makes industrial-grade flanges for a range of applications. We have advanced production and a global presence to deliver solutions with precision engineering. Flanges play an important role in most piping systems; they provide secure connections and leak-proof joints for industries such as oil and gas, power and construction. As one of the trusted flanges manufacturers in Mumbai, we manufacture slip-on, weld neck, blind, and socket weld flanges through various sizes and ratings in stainless steel, carbon steel, and alloy steel. We fulfill international and national quality standards such as ASME, ANSI, DIN, and ASTM. As an ISO 9001:2008 certified company we take utmost care with quality control, testing, and timely delivery in customer assurance at the best price.

What is Flange?

A flange is a protruding ridge or rim used to strengthen or distribute load, commonly used to connect pipes, valves, pumps and other equipment to form a piping system. This enhances the ease of maintenance, inspection and modification. Strong points for leak-proof, secure connection using bolts and gaskets. Compared with welded joints, flanges allow for easier disassembly and reassembly. Proper sealing procedures regarding the gasket selection and torque tightening for a flange seal will prevent leakage and will also help extend the life of the assembly. Material selection, load-bearing capacity and routine checks are key to reliability as neglecting these can lead to failures due to bolt loosening or gasket blowout. A flange installation guide should be followed to ensure correct assembly maximizing the system's life and efficiency in industrial applications.

Flanges

Best Materials for Flanges and Why

Flanges are made from high-quality materials to ensure durability, strength and resistance to extreme conditions. Different materials are chosen based on their performance in various industrial applications.

Stainless Steel Flanges: High corrosion resistance and excellent durability in harsh environments.

Alloy Steel Flanges: Enhanced strength and toughness for high-pressure applications.

Carbon Steel Flanges: Cost-effective with excellent mechanical properties for various industries.

Low Temperature Carbon Steel Flanges: Ideal for sub-zero conditions, maintaining strength and impact resistance.

Duplex Stainless Steel Flanges: Superior corrosion resistance with high strength for demanding applications.

Inconel 600 Flanges: Exceptional heat and oxidation resistance for extreme chemical and thermal environments.

How Flanges Are Manufactured?

We follow strict flange manufacturing standards to ensure durability and performance.

Raw Material Selection:

The process begins with selecting high-quality raw materials such as carbon steel, stainless steel, alloy steel, and other metals, ensuring compliance with flange certification requirements like MTR certification for flanges.

Types of Processes in Flange Manufacturing:

Different technique manufacturing methods are used, including:

  • Forging Process: Heated metal is shaped under high pressure using a flange manufacturing machine, producing stronger forged vs cast flanges.
  • Casting Process: Molten metal is poured into a mold, commonly used by world-class custom flanges manufacturers for complex designs.
  • Cutting from Plate: Ideal for large-diameter and non-standard flanges, ensuring precise dimensions.
  • Rolled Ring Process: Used in flange production process for large-sized flanges, providing superior strength.
  • Heat Treatment: Enhances mechanical properties such as hardness, toughness, and corrosion resistance.
  • Machining & Finishing: CNC machining ensures precise dimensional accuracy, followed by processes like drilling, facing, and threading for proper fitment.
  • Surface Treatment & Coating: Protective coatings like galvanization and epoxy coating are applied to enhance durability and corrosion resistance.
  • Testing & Quality Control: Strict flange quality testing is performed, including hardness checks, hydrostatic pressure tests, and dimensional inspections, to meet flange manufacturing standards.
  • Final Inspection & Certification: Every flange is third-party inspected for quality assurance, which ensures that it meets flange certification standards such as EN 10204 3.1 or 3.2. Flange MTR certification ensures traceability and material quality.

Different Types of Flanges

There are different kinds of flanges to accommodate different industrial uses providing safe connections and effective flow in piping systems.The following is a table summarizing the different types of flanges, their design, functions and face types.

Threaded Flange

Socket Weld Flange

Slip On Flange

Blind Flange

Weld Neck Flange

Lap Joint Flange

Reducing Flange

Elbow Flange


What Are the Benefits of Flanges?

The most significant flange benefits are the strength, security and efficiency with which they provide a connection within piping systems for industries. Flanges improve pipe flange applications through durability, high structural strength and simplicity in maintenance. The corrosion resistance feature shields against rust and chemical exposure, making them ideal for harsh environments. The flanges accommodate high pressure management and extreme heat resistance with a guarantee for reliability in aggressive applications. Its leak prevention functionality ensures a tight, secure seal, minimizing the likelihood of fluid leakage. With options for customization, flanges come in various sizes, materials, and pressure ratings to meet particular industry requirements. As an economical solution it keeps long term maintenance costs low while ensuring safety & compliance standards. These advantages of industrial flanges make it a necessity for secure and efficient piping systems.


What is flange specification?

Flange specification refers to the detailed parameters that define a flange’s dimensions, material, pressure rating, face type and compliance with industry standards. The following are the specifications of flanges

Flanges Specifications
Flanges Types Slip-On, Weld Neck, Long Weld Neck, Threaded, Blind, Companion, Lap Joint
Class 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS ASA 150, ASA 300, PN 6,10,16,25, 40,64,100,160 ETC. available with NACE MR 01-75
Size 1/2″ (15 NB) to 48″ (1200NB) DN10~DN5000
Type Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ), Lap-Joint Face (LJF), Large Male-Female (LMF), Small Male-Female (SMF), Large Tongue & Groove, Small Tongue, Groove
Grades
Stainless Steel ASTM / ASME 201, 202, 301, 304, 304L, 310, 310S, 316L, 316TI, 317, 317L, 321, 347, 409, 409M, 409L, 410, 410S, 420, 430, 431, 441, 444, 446, 17.4PH, 904L
Super Duplex Steel S32750
Duplex Steel ASTM / ASME SA 790 UNS NO S 31803 , S 32205 , S 32550 , S 32750 , S 32760.
Carbon Steel ASTM / ASME A 335 GRP 1 , P 5 , P 9 , P 11 , P 12 , P 22 , P 23 , P 91
Alloys Steel ASTM / ASME A 691 GRP1 CR , 1 1/4 CR , 2 1/4 CR , 5 CR , 9CR , 91.
Nickel Alloys Nickel Alloys 200, Nickel Alloys 201
Titanium Grade 1, Grade 4, Grade 5(Ti 6Al-4V), Grade 6(Ti 5Al-2.5Sn), Grade 7, Grade 11, Grade 12, 8Ai-1Mo-1V, Grade 9(3Al-2.5V), 6Al-6V-25n, 6Al-2Sn-4Zr-2Mo, 6Al-7Nb, Grade 23(Ti 6AL-4V ELI), Grade 5 ELI
Inconel Inconel 600, Inconel 601, Inconel 625, Inconel 625LCF, Inconel 686, Inconel 718, Inconel 800, Inconel 825, Inconel X-750 , Inconel 690, Inconel 602, Inconel 617, Inconel 925, Inconel A-289, Inconel AL-6XN, AL-904L
Hastelloy Hastelloy C-22, Hastelloy C-276, Hastelloy C-2000, Hastelloy C-4, Hastelloy X, Hastelloy B, Hastelloy N, Hastelloy G
Molybdenum ASTM / ASME A 182 GR F 5, F 9 , F 11 , F 12 , F 22 , F 91, ASTM B387, Ferro Molybdenum
Cobalt Cobalt HS-6, Cobalt HS-4, Cobalt HS-25, Sterlite Grade 1, Sterlite Grade 6, Sterlite Grade 12, Sterlite Grade 21
Niobium ASTM B394, R04200 R04210
Nimonic Nimonic75, Nimonic80, Nimonic85, Nimonic90, Nimonic263, etc
Tungsten W1 WAl1, W61, etc, Carbonite Tungsten, Copper Tungsten, Nickel Tungsten
Nichrome Nichrome90, Nichrome80, Nichrome80A, Nichrome RW80, Nichrome75, etc
Magnesium Magnesium AL017100, AL017140, AL017150, AL017160, AL017200, AL017210, AL017250, etc.
Tantalum Tantalum – Grade 1.
Monel Monel 400, Monel k500
MU-METAL MU-METAL
Zirconium Zirconium 702, Zirconium 705, Zirconium 705, Zirconium-2, Zirconium-4
Beryllium Copper Alloy 25 UNSC17200
Aluminium 1050,1100, 2017, 7150, 7178, 7575, 2050, 7085, 2011 A92011, 2014A A92014, 2024 A92024, 2219, 5052 A95052, 5083 A95083, 5754, 6061 A96061 A86061, 6063, 6082 A96082, 7071 7020, 7050 A97050, 7075 A97075 A87075, 7175
Copper Alloys C 11000, C 10200, C 12200, C 51100, C 51000, C 51900, C 52000, C 52100, C 74500, C 75700, C 75400, C 76400, C 77000, C 21000, C 22000, C 23000, C 24000, C 26000, C 26800, C 27000, C 27200, C 28000

Chemical composition of Flange

The chemical composition depends on its material type, affecting its strength, corrosion resistance and durability.

Grade C Mn Si P S Cr Mo
F1 0.15 max 0.3-0.6 0.5 0.03 0.03 4-6 0.44-0.65
F5 0.15 max 0.3-0.6 0.5-1.0 0.03 0.03 4-6 0.44-0.65
F9 0.15 max 0.3-0.6 0.5-1.0 0.03 0.03 8-10 0.9-1.1
F11 0.5-0.15 0.3-0.6 0.5-1.0 0.03 0.03 1.0-1.5 0.44-0.65
F12 0.15 max 0.3-0.6 0.5 0.03 0.03 4-6 0.44-0.65
F22 0.50.15 max 0.3-0.6 0.5 0.03 0.03 4-6 0.44-0.65
F91 0.15 max 0.3-0.6 0.5-1.0 0.03 0.03 8-10 0.9-1.1

Flanges: Strength & Mechanical Properties

Flanges are made to support high pressure, maximum temperature and maximum load but with strength and toughness. Its primary mechanical properties determine the performance and reliability of Steel Flange under industrial conditions.

Grade Tensile Strength Yield Strength (0.2%Offset) Elongation
F1 275 485 20 %
F5 275 485 20 %
F9 380 585 20 %
F11 205 415 20 %
F12 275 485 20 %
F22 205 415 20 %
F91 380 585 20 %

What are the Standard Flange Material Grades and Sizes

The following are the standard flange material grades and sizes used in industrial applications As one of the Best ASTM flange suppliers in India, we offer high-quality flanges in various materials and dimensions to meet diverse requirements.

Flange Size (NPS / DN) Nominal Diameter (in/mm) Pressure Ratings (ASME) Drilling Standards
½" to 24" (DN15 – DN600) 15 mm – 600 mm 150#, 300#, 600#, 900#, 1500#, 2500# ANSI / ASME B16.5
26" to 60" (DN650 – DN1500) 650 mm – 1500 mm 75#, 150#, 300#, 400# ASME B16.47 Series A & B
DN10 to DN2000 10 mm – 2000 mm PN6, PN10, PN16, PN25, PN40 DIN / EN1092-1
Customized sizes As per client requirement As per design API 605, MSS SP-44, AWWA C207

Most Popular Flange Grades

Flanges come in a wide range of material grades, which are specifically engineered to suit certain industrial applications. Selection of flange material is based on pressure, temperature and corrosion requirements. The following are some of the most popularly utilized flange grades by industries.

Carbon Steel Flange Grades

Carbon steel flanges are widely used due to their high strength, durability and cost-effectiveness. These flanges are ideal for high-pressure and high-temperature applications.

  • ASTM A105: This is the most commonly used carbon steel material for forged flanges. It is suitable for high-temperature applications and provides excellent mechanical properties.
  • ASTM A350 LF2: Designed for low-temperature environments, this material offers excellent impact toughness and is commonly used in cryogenic and sub-zero applications.
  • ASTM A694 (F42, F52, F60, F65, F70): These high-strength carbon steel grades are primarily used in high-pressure transmission pipelines. They provide different strength levels, ensuring suitability for demanding applications.

Stainless Steel Flange Grades

Stainless steel flanges are known for their superior corrosion resistance, making them suitable for harsh environments, including chemical processing and marine applications.

  • 304: A versatile stainless steel grade that offers good corrosion resistance and is widely used in general piping applications.
  • 316: Enhanced with molybdenum, this grade provides excellent resistance to chloride corrosion, making it ideal for marine and chemical industries.
  • 321: Contains titanium, which stabilizes the material at high temperatures, reducing the risk of carbide precipitation.
  • 904L: A high-alloy stainless steel with exceptional resistance to acidic and chloride-rich environments, ensuring superior performance in aggressive conditions.

Alloy Steel Flange Grades

Alloy steel flanges are used in industries requiring high strength, heat resistance and superior mechanical properties. These flanges are commonly found in power plants, refineries and high-pressure systems.

  • ASTM A182 F5: Contains chromium and molybdenum, making it resistant to heat and oxidation in high-temperature environments.
  • ASTM A182 F9: Offers excellent strength and corrosion resistance, making it ideal for high-temperature industrial processes.
  • ASTM A182 F11: Commonly used in moderate-temperature and high-pressure applications such as steam pipelines and power plants.
  • ASTM A182 F22: Suitable for use in pressure vessels and steam piping due to its high creep strength.
  • ASTM A182 F91: Known for its outstanding high-temperature strength and creep resistance, making it suitable for extreme industrial conditions.

Duplex & Super Duplex Stainless Steel Flanges

These flanges offer a combination of high strength and superior corrosion resistance, making them ideal for harsh and corrosive environments, including offshore and chemical industries.

  • ASTM A182 F51 (Duplex 2205): Features a balanced microstructure of austenite and ferrite, providing excellent corrosion resistance and high mechanical strength.
  • ASTM A182 F53 (Super Duplex 2507): Offers superior resistance to pitting and crevice corrosion in highly corrosive environments such as marine and chemical processing.
  • ASTM A182 F55 (Super Duplex): Provides enhanced strength and durability for applications requiring extreme corrosion resistance.

Nickel Alloy Flange Grades

Nickel alloy flanges are highly resistant to heat, oxidation and corrosive environments, making them suitable for aerospace, chemical and high-temperature applications.

  • Inconel 800, 825, 600, 625, 601: These nickel-based alloys provide excellent thermal stability, oxidation resistance and mechanical strength at high temperatures.
  • Nickel 200, Nickel 201: Known for their exceptional resistance to acids, caustic solutions and extreme temperature conditions, making them ideal for chemical processing industries.

Copper-Nickel (Cu-Ni) Flange Grades

Copper-nickel flanges are mostly used in marine and shipbuilding industries, because of their effective seawater corrosion and biofouling resistance.

  • ASTM B151 UNS C70600 (90/10 Cu-Ni): Gives excellent corrosion resistance and high durability in marine applications such as ship hulls and seawater piping.
  • ASTM B151 UNS C71500 (70/30 Cu-Ni): Has more strength and more resistance to biofouling, making it suitable for the offshore and shipbuilding industries.

All these grades of flanges are guaranteed to give reliability, efficiency and performance over time in different industrial applications.


ASTM vs. DIN vs. ASME Flanges – What’s the Difference?

Flanges adhere to various international standards such as ASTM, DIN and ASME, each having its specifications regarding materials, sizes, and pressure classes.Knowledge of their variations guarantees the proper choice for piping systems according to regional and industrial needs.

Introduction to Flange Standards

ASTM, DIN and ASME are the most common flange standards applied in industry. The standards vary in measurement units, pressure ratings, and material specifications to ensure that flanges comply with certain engineering and safety standards. Selecting the appropriate standard is based on considerations such as region, application and performance needs.

ASTM Flanges (American Standard)

ASTM flanges are extensively adopted in the international and USA marketplaces, centering mainly around material properties as well as mechanical performance.Such flanges aim to satisfy tight ASTM material standards, guaranteeing reliability under variable operating conditions. Typical ASTM flange materials involve ASTM A105 (carbon steel) and ASTM A182 (stainless steel).These flanges can be found in pressure classes ranging from Class 150 to Class 2500 and are consequently ideal for applications within the oil & gas, refineries, power plants and chemical processing sectors.

DIN Flanges (European Standard)

DIN flanges adhere to the Deutsches Institut für Normung (DIN) standards, which are widely applied in European industries. In contrast to ASTM flanges, DIN flanges employ metric units and PN (Pressure Nominal) ratings rather than class ratings. Typical materials for DIN flanges are DIN 1.4404 (stainless steel) and DIN 1.0570 (carbon steel). DIN flanges have pressure ratings from PN6 to PN400, which makes them suitable for European piping systems, petrochemical plants and water treatment plants.

ASME Flanges (Engineering Standard)

ASME flanges are used in the USA and worldwide, with a high emphasis on engineering design and pressure retention. The ASME B16.5 and ASME B16.47 standards specify the dimensions, materials and pressure ratings for these flanges, which provide high performance in industrial applications. ASME flanges are produced in Class 150 to Class 2500 pressure ratings, which makes them ideal for high-pressure, high-temperature applications. They find extensive application in power generation, chemical processing, and heavy industry applications where the requirements are resistance and adherence to engineering standards.

Key Differences Between ASTM, DIN and ASME Flanges

  • Region of Use: ASTM and ASME flanges are mainly used in the USA and international markets, while DIN flanges are standard in Europe.
  • Measurement Unit: ASTM and ASME flanges use inches and PSI, whereas DIN flanges use metric units and bar.
  • Pressure Ratings: ASTM and ASME flanges adhere to Class Ratings (150–2500), while DIN flanges utilize PN Ratings (PN6–PN400).
  • Application: ASTM flanges are chosen on the basis of material properties, DIN flanges are utilized in European metric-based systems and ASME flanges are applied for industrial applications at high pressure.

Which One to Choose?

The choice of the appropriate flange standard depends on the requirements of the industry and the regional regulations.ASTM flanges are perfect for situations where American material standards are required, thereby guaranteeing toughness and rigidity. DIN flanges are used exclusively when piping systems are based on European metrics thus providing accuracy and compatibility. ASME flanges should be used specifically for high-pressure applications industrially, where stringent adherence to engineering standards is mandated.

What is the ASME Code for Flanges?

The ASME B16.5 and ASME B16.47 codes specify the size, materials, pressure rating and tolerances for industrial piping system flanges. The codes provide the uniformity, safety and performance in various industries.

What is the ASME B16.47 Flange?

The ASME B16.47 specification applies to large diameter flanges (NPS 26 to NPS 60), designed for high pressure and high temperature applications. It is extensively used in oil & gas, power generation, refineries and chemical processes, delivering safe and efficient pipeline connections.


Why Choose Silver Tubes?

We are a global quality custom flanges manufacturer renowned for providing superior quality and precision-engineered products that meet the standards of flange manufacturing. Our cutting-edge facility boasts world-class technology and high-precision flange manufacturing equipment which allows us to manufacture both standard and custom flanges with perfection. We meet globally recognized certifications including ISO 9001, PED, ASTM, ASME, DIN and EN 10204 3.1/3.2, that guarantee strict flange quality testing and flange certification requirements. With bulk inventory, we provide competitive rates without compromising quality, guaranteeing bulk supply and timely order delivery.Our assured delivery network enables us to dispatch flanges all over India and abroad, gaining the confidence of top industrial buyers. We offer committed assistance, technical support by experts, and warranty-ensured products for long-lasting reliability. Also, we deliver MTR certification for flanges, EN 10204 3.1/3.2 Certification, and ASME & ASTM Compliance Reports, testing material composition and compliance with global standards. Choose us for unparalleled quality, accuracy, and reliability.


What are the applications of flanges?

Building & Construction

Automotive manufacturing

Marines Application

Energy Production

Chemical Processing

Healthcare and Medical

Home Appliances

Oil & Gas


Why Flanges Are Preferred in These Industries?

Our flanges are widely used in industrial piping systems due to their strength, durability and ease of maintenance. They provide secure, leak-proof connections, making them ideal for handling high pressure, extreme temperatures and corrosive environments. Their customizable designs allow them to be tailored for specific needs, such as stainless steel for hygienic food processing or nickel alloys for marine applications. With versatility and reliability, flanges remain essential for safe and efficient industrial operations worldwide.

Flanges FAQ: Everything You Need to Know

Our Duplex Steel Flanges provide a balance of corrosion resistance and strength and are therefore suited for chemical processing, marine, and oil & gas industry applications. They possess greater mechanical strength than general stainless steel and modest resistance to chloride stress corrosion cracking. Super Duplex Steel Flanges offer increased resistance to corrosion, increased tensile strength and enhanced durability because of the increased chromium, molybdenum and nitrogen content. Ideally suited for intense pressure and extremely corrosive environments - like offshore oil rigs, seawater desalination plants, and chemical processing facilities - these are super duplex flanges. It is their superior performance in aggressive conditions that makes them the preferred choice for demanding applications.

SAE flange standard is established by the Society of Automotive Engineers (SAE) and is generally intended for hydraulic flange connections. The most universal standard is SAE J518, which provides dimensions, pressure ratings and design for split and solid flanges used in high-pressure hydraulic systems. It is widely used in mobile equipment, industrial equipment and fluid power applications.

Flanges are connected in a piping system by bolting two flange faces with a gasket in between to provide a leak-proof, secure seal. The connection is secured with bolts and nuts, tightening with even pressure to avoid leaks. Flanges may be welded, threaded or clamped to the pipes based on the application. Some of the general flange connection styles are weld neck, slip-on, socket weld, threaded, lap joint, and blind flanges tailored to different pressure and operation requirements.

The size of the flange is determined by measuring outer diameter (OD), inner diameter (ID), bolt circle diameter (BCD), number and size of bolt holes, flange thickness and pressure rating, etc., and these measurements ensure proper fitment and compatibility with piping systems. Using calipers, tape measures or flange gauges accurate measurements of flange dimensions help in exact installation.

The weight of a round bar can be calculated using the formula: Weight (kg)=π4×Diameter2×Length×Density\text{Weight (kg)} = \frac{\pi}{4} \times \text{Diameter}^2 \times \text{Length} \times \text{Density} For stainless steel (density ~ 7.85 g/cm³), the simplified formula is: Weight (kg/m)=0.006165×Diameter2\text{Weight (kg/m)} = 0.006165 \times \text{Diameter}^2 (Where Diameter is in mm)

Before purchasing, ensure the round bars come with quality certifications like ISO 9001 (Quality Management), EN 10204 3.1/3.2 (Material Traceability), ASTM / ASME Compliance, PED (Pressure Equipment Directive) and Ultrasonic Testing (UT) and Non-Destructive Testing (NDT) Reports.
These certifications ensure quality, durability, and compliance with international industry standards.