ANSI B16.5 and ANSI B16.36 Stainless Steel, Carbon Steel & Alloy Steel Orifice Flange Manufacturer & Exporter
Amardeep Steel Centre is one of India's most trusted manufacturers, suppliers, and exporters of high-quality ASME/ANSI B16.5 and ANSI B16.36 Orifice Flanges. With decades of experience in precision flange manufacturing, we supply orifice flanges to oil & gas, petrochemical, power generation, water treatment, and process industries worldwide.
Our orifice flanges are manufactured from premium-grade raw materials including Stainless Steel, Carbon Steel, Alloy Steel, Duplex, Super Duplex, Nickel Alloys, and Copper Alloys. Available in a wide range of sizes (1/2" to 48"), pressure classes (150 LBS to 2500 LBS), and face types, our flanges comply with all major international standards including ASME, ANSI, DIN, BS, JIS, and EN.
We carry ready stock of ANSI B16.5 & B16.36 Orifice Flanges and provide custom fabrication as per client drawings and specifications. Our ISO-certified manufacturing facility ensures every flange meets stringent quality benchmarks before dispatch. We manufacture and supply all major orifice flange types in accordance with ASME B16.5 and ANSI B16.36 standards for critical industrial flow measurement applications.
Table of Contents
- Orifice Flanges Manufacturer
- What Are Orifice Flanges?
- Key Features
- Specifications
- Orifice Flange Types
- Class 150 Flange Dimensions
- Class 300 Flange Dimensions
- ANSI B16.36 Class 150 Dimensions
- ANSI B16.36 Class 300 Dimensions
- Material Specification
- Standards & Specifications
- Pressure Ratings
- Applications
- Quality Assurance & Testing
- Why Choose Amardeep Steel Centre?
- Frequently Asked Questions
What Are Orifice Flanges?
Orifice flanges are specialized flanges that incorporate built-in pressure tap holes (also called jack screws or tapped holes) and are used in piping systems in conjunction with orifice plates or flow nozzles. They are used instead of standard pipe flanges when accurate flow measurement of liquids or gases is required.
Each orifice flange pair features two pipe taps that measure the differential pressure drop created as the fluid passes through the orifice plate. This pressure drop is directly proportional to the flow rate, making orifice flanges a critical component for accurate flow metering in process pipelines.
The orifice plate is a separate component (not part of the flange assembly) and is positioned concentrically within the pipe bore. The plate typically has a bore diameter of 30% to 75% of the pipe's internal diameter, creating the pressure differential used for measurement.
Different orifice flange types are used depending on the piping configuration, pressure class, and process requirements. Common configurations include weld neck, slip-on, socket weld, and threaded orifice flanges. Each design is selected based on the required orifice flange use in flow measurement, pressure monitoring, and process control systems.
Key Features of Amardeep Steel Orifice Flanges
- Built-in precision-machined pressure tap holes (jack screws) for accurate flow monitoring
- Leak-proof construction with precision-machined mating surfaces
- Available in Raised Face (RF) and Ring Type Joint (RTJ) face configurations
- Manufactured to ASME B16.36, B16.5, and all major international standards
- Supplied as matched pairs (orifice flange union) for easy installation
- Compatible with all standard orifice plates, sealing gaskets, and stud bolt sets
- High-pressure and high-temperature rated for demanding service environments
- Custom drilling, special materials, and non-standard sizes available on request
- 100% hydrostatic testing and dimensional inspection before dispatch
- ISO-certified manufacturing with full material traceability
ASME B16.5 Orifice Flange Specifications
| Parameter | Details |
|---|---|
| Size Range | 1/2" (15 NB) to 48" (1200 NB) |
| Pressure Class | 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS |
| Standards | ANSI B16.5, ANSI B16.47, MSS SP44, ANSI B16.36, ANSI B16.48 |
| Face Types | Raised Face (RF), Ring Type Joint (RTJ), Flat Face (FF), Large Male-Female (LMF), Lap-Joint Face (LJF) |
| Types | Weld Neck, Slip-On, Socket Weld, Threaded/Screwed |
| Material | Stainless Steel, Carbon Steel, Alloy Steel, Duplex, Super Duplex, Nickel Alloys, Copper Alloys |
| DIN Standard | ND-6, 10, 16, 25, 40 Etc. |
| Production Technique | Forged, Heat Treated, Machined |
| Test Certificates | EN 10204/3.1B, Raw Materials Certificate, 100% Radiography Test Report, Third Party Inspection |
| Coating | Oil Black Paint, Anti-rust Paint, Zinc Plated, Cold & Hot Dip Galvanized |
Orifice Flange Types
1. Weld Neck Orifice Flange
Weld neck orifice flanges feature a long tapered hub that transitions smoothly into the pipe wall, distributing stress over a larger area. They are the most common type used in high-pressure and high-temperature applications. The butt weld connection provides maximum strength and leak resistance, making them ideal for critical flow measurement service in refineries, chemical plants, and power stations.
2. Slip-On Orifice Flange
Slip-on orifice flanges slide over the pipe and are welded both inside and outside for a secure connection. They are easier to install and align than weld neck types and are used for moderate pressure and temperature services. Available with raised face or flat face configurations, slip-on orifice flanges are a cost-effective solution for lower pressure flow measurement applications.
3. Socket Weld Orifice Flange
Socket weld orifice flanges are specifically designed for smaller pipe sizes (typically up to 2") in high-pressure service. The pipe inserts into a recessed socket end and is fillet welded externally. These flanges provide excellent strength and leak protection and are widely used in hydraulic lines, instrumentation piping, and chemical process lines requiring precise flow measurement.
4. Threaded (Screwed) Orifice Flange
Threaded orifice flanges feature internal threads that engage directly with the pipe threads, eliminating the need for welding. They are ideal for systems where welding is not practical, such as flammable or explosive environments. Available in NPT and BSP thread forms, these flanges are used in low-to-moderate pressure applications for gas and liquid flow measurement.
ASME B16.5 Class 150 Flange Dimensions
| Nominal Size | Outside Dia. O | Thk. C | Raised Face Dia. R | Hub Dia. X | Bore (WN) B1 | Length Y1 | Bolt Circle | No. Holes | Weight (WN) |
|---|---|---|---|---|---|---|---|---|---|
| 1/2" | 3.50 | 0.44 | 1.38 | 1.19 | 0.88 | 0.62 | 2.38 | 4 | 2 |
| 3/4" | 3.88 | 0.50 | 1.69 | 1.50 | 1.09 | 0.62 | 2.75 | 4 | 2 |
| 1" | 4.25 | 0.56 | 2.00 | 1.94 | 1.36 | 0.69 | 3.12 | 4 | 3 |
| 2" | 6.00 | 0.75 | 3.62 | 3.06 | 2.44 | 1.00 | 4.75 | 4 | 6 |
| 3" | 7.50 | 0.94 | 5.00 | 4.25 | 3.57 | 1.19 | 6.00 | 4 | 10 |
| 4" | 9.00 | 0.94 | 6.19 | 5.31 | 4.60 | 1.31 | 7.50 | 8 | 15 |
| 6" | 11.00 | 1.00 | 8.50 | 7.56 | 6.72 | 1.56 | 9.50 | 8 | 24 |
| 8" | 13.50 | 1.12 | 10.62 | 9.69 | 8.72 | 1.75 | 11.75 | 8 | 39 |
| 10" | 16.00 | 1.19 | 12.75 | 12.00 | 10.88 | 1.94 | 14.25 | 12 | 52 |
| 12" | 19.00 | 1.25 | 15.00 | 14.38 | 12.88 | 2.19 | 17.00 | 12 | 80 |
| 14" | 21.00 | 1.38 | 16.25 | 15.75 | 14.14 | 2.25 | 18.75 | 12 | 110 |
| 16" | 23.50 | 1.44 | 18.50 | 18.00 | 16.16 | 2.50 | 21.25 | 16 | 140 |
| 18" | 25.00 | 1.56 | 21.00 | 19.88 | 18.18 | 2.69 | 22.75 | 16 | 150 |
| 20" | 27.50 | 1.69 | 23.00 | 22.00 | 20.20 | 2.88 | 25.00 | 20 | 180 |
| 24" | 32.00 | 1.88 | 27.25 | 26.12 | 24.25 | 3.25 | 29.50 | 20 | 260 |
ASME B16.5 Class 300 Flange Dimensions
| Nominal Size | Outside Dia. O | Thk. C | Raised Face Dia. R | Hub Dia. X | Bore B1 | Length Y1 | Bolt Circle | No. Holes | Weight (WN) |
|---|---|---|---|---|---|---|---|---|---|
| 1/2" | 3.75 | 0.56 | 1.38 | 1.50 | 0.88 | 0.88 | 2.62 | 4 | 2 |
| 1" | 4.88 | 0.69 | 2.00 | 2.12 | 1.36 | 1.06 | 3.50 | 4 | 4 |
| 2" | 6.50 | 0.88 | 3.62 | 3.31 | 2.44 | 1.31 | 5.00 | 8 | 9 |
| 3" | 8.25 | 1.12 | 5.00 | 4.62 | 3.57 | 1.69 | 6.62 | 8 | 15 |
| 4" | 10.00 | 1.25 | 6.19 | 5.75 | 4.57 | 1.88 | 7.88 | 8 | 25 |
| 6" | 12.50 | 1.44 | 8.50 | 8.12 | 6.72 | 2.06 | 10.62 | 12 | 42 |
| 8" | 15.00 | 1.62 | 10.62 | 10.25 | 8.72 | 2.44 | 13.00 | 12 | 67 |
| 10" | 17.50 | 1.88 | 12.75 | 12.62 | 10.88 | 2.62 | 15.25 | 16 | 91 |
| 12" | 20.50 | 2.00 | 15.00 | 14.75 | 12.88 | 2.88 | 17.75 | 16 | 140 |
| 16" | 25.50 | 2.25 | 18.50 | 19.00 | 16.16 | 3.25 | 22.50 | 20 | 250 |
| 20" | 30.50 | 2.50 | 23.00 | 23.12 | 20.20 | 3.75 | 27.00 | 24 | 400 |
| 24" | 36.00 | 2.75 | 27.25 | 27.62 | 24.25 | 4.19 | 32.00 | 24 | 580 |
ANSI B16.36 Class 150 Orifice Flange Dimensions (mm)
| Nom. Size | O (mm) | C (mm) | R (mm) | X (mm) | A (mm) | Y (mm) | No. Holes | Bolt Circle (mm) |
|---|---|---|---|---|---|---|---|---|
| 1" | 124 | 38.1 | 50.8 | 53.8 | 33.5 | 82.6 | 4 | 88.9 |
| 1-1/2" | 155.4 | 38.1 | 73.2 | 69.9 | 48.3 | 85.9 | 4 | 114.3 |
| 2" | 165.1 | 38.1 | 91.9 | 84.1 | 60.5 | 85.9 | 8 | 127 |
| 2-1/2" | 190.5 | 38.1 | 104.6 | 100.1 | 73.2 | 88.9 | 8 | 149.4 |
| 3" | 209.6 | 38.1 | 127 | 117.3 | 88.9 | 88.9 | 8 | 168.1 |
| 4" | 254 | 38.1 | 157.2 | 146.1 | 114.3 | 91.9 | 8 | 200.2 |
| 6" | 317.5 | 38.1 | 215.9 | 206.2 | 168.4 | 100.1 | 12 | 269.7 |
| 8" | 381 | 41.1 | 269.7 | 260.4 | 219.2 | 111.3 | 12 | 330.2 |
| 10" | 444.5 | 47.8 | 323.9 | 320.5 | 273.1 | 117.3 | 16 | 387.4 |
| 12" | 520.7 | 50.8 | 381 | 374.7 | 323.9 | 130 | 16 | 450.9 |
| 14" | 584.2 | 53.8 | 412.8 | 425.5 | 355.6 | 142.7 | 20 | 514.4 |
| 16" | 647.7 | 57.2 | 469.9 | 482.6 | 406.4 | 146.1 | 20 | 571.5 |
| 18" | 711.2 | 60.5 | 533.4 | 533.4 | 457.2 | 158.8 | 24 | 628.7 |
| 20" | 774.7 | 63.5 | 584.2 | 587.2 | 508 | 162.1 | 24 | 685.8 |
| 24" | 914.4 | 69.9 | 692.2 | 701.5 | 609.6 | 168.1 | 24 | 812.8 |
Note: All dimensions are in millimeters (mm) unless otherwise specified. O = Outside Diameter, C = Flange Thickness, R = Hub OD, X = Weld Neck OD, A = Bore Diameter, Y = Welding Neck Length.
ANSI B16.36 Class 300 Orifice Flange Dimensions
| Size (in) | Size (mm) | Outer Dia. | Flange Thick. | Hub OD | RF Dia. | PCD | No. Bolts | Weight (kg) |
|---|---|---|---|---|---|---|---|---|
| 1 | 25 | 125 | 36.6 | 54 | 50.8 | 88.9 | 4 | 4.5 |
| 1-1/2 | 40 | 155 | 36.6 | 70 | 73 | 114.3 | 4 | 6.5 |
| 2 | 50 | 165 | 36.6 | 84 | 92.1 | 127 | 8 | 7 |
| 2-1/2 | 65 | 190 | 36.6 | 100 | 104.8 | 149.2 | 8 | 7.5 |
| 3 | 80 | 210 | 36.6 | 117 | 127 | 168.3 | 8 | 9.4 |
| 4 | 100 | 255 | 36.6 | 146 | 157.2 | 200 | 8 | 13.2 |
| 6 | 150 | 320 | 36.6 | 206 | 215.9 | 269.9 | 12 | 14.6 |
| 8 | 200 | 380 | 39.7 | 260 | 269.9 | 330.2 | 12 | 30 |
| 10 | 250 | 445 | 46.1 | 321 | 323.8 | 387.3 | 16 | 41 |
| 12 | 300 | 520 | 49.3 | 375 | 381 | 450.8 | 16 | 62 |
| 14 | 350 | 585 | 52.4 | 425 | 412.8 | 514.4 | 20 | 84 |
| 16 | 400 | 650 | 55.6 | 483 | 469.9 | 571.5 | 20 | 111 |
| 18 | 450 | 710 | 58.8 | 533 | 533.4 | 628.6 | 24 | 138 |
| 20 | 500 | 775 | 62 | 587 | 584.2 | 685.8 | 24 | 171 |
| 24 | 600 | 915 | 68.3 | 702 | 692.2 | 812.8 | 24 | 247 |
Note: Weight values are approximate and may vary based on material grade. Contact us for Class 600, 900, 1500, and 2500 dimension tables.
Grade-Wise Material Specification
Stainless Steel Orifice Flanges
ASTM A182, A240 – Grades: F304, F304L, F304H, F316, F316Ti, F316H, F316L, F316LN, F309S, F309H, F310S, F310H, F317, F317L, F321, F321H, F347, F347H, F201, F202, F904L
Carbon Steel Orifice Flanges
ASTM/ASME A/SA 105, A350 LF2, A181, A516 Gr.70, A36, A694 F42, F46, F52, F60, F65, F70
Alloy Steel Orifice Flanges
ASTM/ASME A/SA 182 & A387 – F1, F5, F9, F11, F12, F22, F91
Nickel Alloy Orifice Flanges
ASTM SB564, SB160, SB472, SB162 – Nickel 200 (N02200), Nickel 201 (N02201), Monel 400 (N04400), Monel 500 (N05500), Inconel 800 (N08800), Inconel 825 (N08825), Inconel 600 (N06600), Inconel 625 (N06625), Inconel 601 (N06601), Hastelloy C276 (N10276), Alloy 20 (N08020)
Duplex & Super Duplex Steel Orifice Flanges
ASTM A182, A240 – F44, F45, F51, F53, F55, F60, F61 | Super Duplex: S32750 / S32760
Copper Alloy Orifice Flanges
ASTM SB61, SB62, SB151, SB152 – UNS C10100, C10200, C70600 (Cu-Ni 90/10), C71500 (Cu-Ni 70/30), Brass 3602/2604/H59/H62
Orifice Flange Standards & Specifications
- ASME/ANSI: B16.5, B16.36, B16.47 Series A & B, B16.48, MSS SP44, API 605
- DIN Standards: DIN 2527, 2566, 2573, 2576, 2627-2638
- British Standards: BS 4504, BS 3293, BS 1560, BS 10
- EN Standards: EN 1092-1, EN 1098
- JIS/KS Standards: JIS B2220, KS B1503
- Australian Standard: AS 2129 Table D, E, H
- Other: AWWA C207, GOST 12820, NFE 29203, UNI 2276, SABS 1123
Pressure Ratings Available
- ANSI/ASME Classes: 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS
- DIN/EN Pressure Ratings: PN6, PN10, PN16, PN25, PN40, PN64, PN160
- JIS Ratings: 5K, 10K, 16K, 20K, 30K, 40K, 63K
Applications of Orifice Flanges
Orifice flanges are critical flow measurement components used across a broad range of process-critical industries that demand real-time, accurate fluid flow analysis:
- Oil & Gas Transmission and Processing – Accurate custody transfer metering and process control
- Petrochemical & Chemical Industries – Flow measurement of corrosive and aggressive media
- Power Generation & Steam Systems – Steam flow monitoring in boiler and turbine systems
- Water & Wastewater Treatment Plants – Water flow measurement and distribution control
- Pharmaceutical Manufacturing – Precise fluid flow control in critical process lines
- Food & Beverage Processing – Hygienic flow measurement in sanitary piping systems
- Industrial Automation & Flow Monitoring – Integration with digital flow transmitters
- Refineries & Onshore/Offshore Platforms – High-pressure and high-temperature service
Quality Assurance & Testing
At Amardeep Steel Centre, every orifice flange undergoes rigorous quality checks at our state-of-the-art testing facility before shipment. Our quality control programme includes:
- Chemical Composition Analysis via Direct-Reading Spectrograph
- Mechanical Testing: Tensile Strength, Yield Strength, Hardness, Impact Testing
- Hydrostatic Pressure Testing (100% of production)
- Ultrasonic Flaw Detection (UT) for internal defects
- Radiographic Testing (RT) / X-Ray Inspection
- Magnetic Particle Inspection (MPI) for surface defects
- Dimensional Inspection as per ANSI B16.5 / B16.36
- PMI (Positive Material Identification) on request
- Third-Party Inspection by TUV, Bureau Veritas, SGS, DNV-GL on request
- EN 10204/3.1B Mill Test Certificates supplied with every lot
Why Choose Amardeep Steel Centre for Orifice Flanges?
- Decades of manufacturing expertise in precision flange production
- ISO-certified operations with strict quality management systems
- Comprehensive ready stock of Class 150 to Class 2500 orifice flanges
- Extensive material range – over 20 material categories available
- Sizes from 1/2" (15 NB) to 48" (1200 NB) in stock and custom sizes available
- Competitive pricing with no compromise on quality or traceability
- Custom fabrication as per client drawings, reverse engineering, and special alloys
- Global logistics capability – we export to 150+ countries worldwide
- Prompt delivery with complete documentation and packing for sea/air freight
- Dedicated technical support team for material selection and specification guidance
Frequently Asked Questions - Orifice Flanges
What is the difference between an orifice flange and a standard flange?
Unlike standard flanges, orifice flanges include two pressure tap holes (jack screws) drilled radially into the flange body. These taps are connected to a differential pressure transmitter to measure the flow rate. Standard flanges do not have these tapping points and are used purely for pipe connection.
What is an orifice flange union?
An orifice flange union refers to a matched pair of orifice flanges (typically weld neck type) supplied together with jack screws, stud bolts, nuts, and gaskets. The two flanges sandwich the orifice plate between them, forming a complete flow measurement assembly.
What sizes are available for ASME B16.36 orifice flanges?
Amardeep Steel Centre supplies ASME B16.36 orifice flanges in sizes ranging from 1/2" (15 NB) to 48" (1200 NB), in all standard pressure classes from 150 LBS to 2500 LBS. Custom sizes outside the standard range are also available on request.
Which material is most commonly used for orifice flanges?
The most commonly used materials are Carbon Steel (ASTM A105) for general service, Stainless Steel 304/316 for corrosive environments, and Alloy Steel F11/F22 for high-temperature applications. For aggressive chemical service, Duplex, Hastelloy, Inconel, and Monel grades are specified.
Do you supply orifice flanges with calibration or flow calculations?
We supply orifice flanges as per dimensional and material standards. Flow calculations, orifice bore sizing, and calibration services are typically performed by the end user or instrumentation engineers using the differential pressure measurement data. We can advise on material and configuration selection based on your service conditions.
