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Weld Neck Orifice Flange Union

• ARO-OPAFU-WN1

What is a Weld Neck Orifice Flange Union?

A Weld Neck Orifice Flange Union is a specialized type of flange used in piping systems to measure the flow rate of fluids. It consists of a weld neck flange and an orifice plate, designed to be welded to the pipe. The orifice plate has a precisely measured hole that creates a pressure drop, allowing for the calculation of flow rate based on differential pressure measurements. This type of union is commonly used in industrial applications where accurate flow measurement is critical, such as in chemical processing, oil and gas, and power generation industries.

Datasheet

Product Data

Overview

Arrotop is a leading manufacturer and supplier of Weld Neck Orifice Flange Unions, engineered for high-pressure applications and built to meet international standards such as ASME and ISO. Widely trusted in industries including oil & gas, chemical, and power, Arrotop delivers dependable performance, timely delivery, and custom-engineered solutions to meet specific flow measurement needs.

The Weld Neck Orifice Flange Union is tailored for high pressure applications, featuring a long, tapered hub for a robust welded connection, ensuring precise bore alignment and reducing stress concentrations.

The Weld Neck Ori ce Flange Union (ARO-OPAFU-WN1) offers reliable performance in high-pressure and high temperature environments. Its secure and precise design ensures accurate flow measurements and robust sealing. With a range of materials and standards compliance, it meets diverse industrial requirements, providing comprehensive documentation for quality assurance.

Features

  • High-Pressure Capability : Ideal for high-pressure and high temperature environments.
  • Secure Welded Seal : Provides a strong, leak-proof connection.
  • Accurate Measurement : Ensures minimal flow disturbance due to precise alignment.

Technical Information

Model Number ARO-OPAFU-WN1
Material SS 304/L, 316/L, Duplex, Super Duplex, Hastelloy, Carbon Steel, Monel, Inconel, Titanium
Orifice Plate Types Square Edge, Eccentric, Conical Entrance, Quarter Circle
Pressure Classes 150, 300, 600, 900, 1500, 2500
Standards ISO 5167-2, ASME MFC-3M, ISO TR 15377, AGA 3 ANSI B16.36, B31.3

Dimensional Data

Class 150 Weld Neck Flange Dimension

Size ( Inch) OD ( mm ) Flange Thickness (mm) Hub OD Weld Neck OD RF Diameter (mm) RF Height (mm) PCD (mm) No of BoIts BoIt Size (UNC)
1/2 90 9.6 30 21.3 34.9 2 60.3 4 1/2
3/4 100 11.2 38 26.7 42.9 2 69.9 4 1/2
1 110 12.7 49 33.4 50.8 2 79.4 4 1/2
1 1/4 115 14.3 59 42.2 63.5 2 88.9 4 1/2
1 1/2 125 15.9 65 48.2 73 2 98.4 4 1/2
2 150 17.5 78 60.3 92.1 2 120.7 4 5/8
2 1/2 180 20.7 90 73 104.8 2 139.7 4 5/8
3 190 22.3 108 88.9 127 2 152.4 4 5/8
3 1/2 215 22.3 122 101.6 139.7 2 177.8 8 5/8
4 230 22.3 135 114.3 157.2 2 190.5 8 5/8
5 255 22.3 164 141.3 185.7 2 215.9 8 3/4
6 280 23.9 192 168.3 215.9 2 241.3 8 3/4
8 345 27 246 219.1 269.9 2 298.5 8 3/4
10 405 28.6 305 273 323.8 2 362 12 7/8
12 485 30.2 365 323.8 381 2 431.8 12 7/8
14 535 33.4 400 355.6 412.8 2 476.3 12 1
16 595 35 457 406.4 469.9 2 539.8 16 1
18 635 38.1 505 457.2 533.4 2 577.9 16 1 1/8
20 700 41.3 559 508 584.2 2 635 20 1 1/8
24 815 41.3 559 508 584.2 2 635 20 1 1/8

Class 300 Weld Neck Flange Dimensions

Size ( Inch) OD ( mm ) Flange Thickness (mm) Hub OD Weld Neck OD RF Diameter (mm) RF Height (mm) PCD (mm) No of BoIts BoIt Size (UNC)
1/2 95 12.7 38 21.3 34.9 2 66.7 4 1/2
3/4 115 14.3 48 26.7 42.9 2 82.6 4 5/8
1 125 15.9 54 33.4 50.8 2 88.9 4 5/8
1 1/4 135 17.5 64 42.2 63.5 2 98.4 4 5/8
1 1/2 155 19.1 70 48.2 73 2 114.3 4 3/4
2 165 20.7 84 60.3 92.1 2 127 8 5/8
2 1/2 190 23.9 100 73 104.8 2 149.2 8 3/4
3 210 27 117 88.9 127 2 168.3 8 3/4
3 1/2 230 28.6 133 101.6 139.7 2 184.2 8 3/4
4 255 30.2 146 114.3 157.2 2 200 8 3/4
5 280 33.4 178 141.3 185.7 2 235 8 3/8
6 320 35 206 168.3 215.9 2 269.9 12 3/8
8 380 39.7 260 219.1 269.9 2 330.2 12 7/8
10 445 46.1 321 273 323.8 2 387.4 16 1
12 520 49.3 375 323.8 381 2 450.8 16 1 1/8
16 650 55.6 483 406.4 469.9 2 571.5 20 1 1/4
18 710 58.8 533 457.2 533.4 2 628.6 24 1 1/4
20 775 62 587 508 584.2 2 685.8 24 1 1/4
20 775 62 587 508 584.2 2 685.8 24 1 1/4
24 915 68.3 702 610 692.2 2 812.8 24 1 1/2

Class 600 Weld Neck Flange Dimension

Size ( Inch) OD ( mm ) Flange Thickness (mm) Hub OD Weld Neck OD RF Diameter (mm) RF Height (mm) PCD (mm) No of BoIts BoIt Size (UNC)
1/2 95 14.3 38 21.3 34.9 7 66.7 4 1/2
3/4 115 15.9 48 26.7 42.9 7 82.6 4 5/8
1 125 17.5 54 33.4 50.8 7 88.9 4 5/8
1 1/4 135 20.7 64 42.2 63.5 7 98.4 4 5/8
1 1/2 155 22.3 70 48.2 73 7 114.3 4 3/4
2 165 25.4 84 60.3 92.1 7 127 8 5/8
2 1/2 190 28.6 100 73 104.8 7 149.2 8 3/4
3 210 31.8 117 88.9 127 7 168.3 8 3/4
3 1/2 230 35 133 101.6 139.7 7 184.2 8 7/8
4 275 38.1 152 114.3 157.2 7 215.9 8 7/8
5 330 44.5 189 141.3 185.7 7 266.7 8 1
6 355 47.7 222 168.3 215.9 7 292.1 12 1
8 420 55.6 273 219.1 269.9 7 349.2 12 1 1/8
10 510 63.5 343 273 323.8 7 431.8 16 1 1/4
12 560 66.7 400 323.8 381 7 489 20/td> 1 1/4
14 605 69.9 432 355.6 412.8 7 527 20 1 3/8
16 685 76.2 495 406.4 469.9 7 603.2 20 1 1/2
18 745 82.6 546 457.2 533.4 7 654 20 1 5/8
20 815 88.9 610 508 584.2 7 723.9 24 1 5/8
24 940 101.6 718 610 692.2 7 838.2 24 1 7/8

Class 900 Weld Neck Flange Dimension

Size ( Inch) OD ( mm ) Flange Thickness (mm) Hub OD Weld Neck OD RF Diameter (mm) RF Height (mm) PCD (mm) No of BoIts BoIt Size (UNC)
1/2 120 22.3 38 21.3 34.9 7 82.6 4 3/4
3/4 130 25.4 44 26.7 42.9 7 88.9 4 3/4
1 150 28.6 52 33.4 50.8 7 101.6 4 7/8
1 1/4 160 28.6 64 42.2 63.5 7 111.1 4 7/8
1 1/2 180 31.8 70 48.2 73 7 123.8 4 1
2 215 38.1 105 60.3 92.1 7 165.1 8 7/8
2 1/2 245 41.3 124 73 104.8 7 190.5 8 1
3 240 38.1 127 88.9 127 7 190.5 8 7/8
4 290 44.5 159 114.3 157.2 7 235 8 1 1/8
5 350 50.8 190 141.3 185.7 7 279.4 8 1 1/4
6 380 55.6 235 168.3 215.9 7 317.5 12 1 1/8
8 470 63.5 298 219.1 269.9 7 393.7 12 1 3/8
10 545 69.9 368 273 323.8 7 469.9 16 1 3/8
12 610 79.4 419 323.8 381 7 533.4 20 1 3/8
14 640 85.8 451 355.6 412.8 7 558.8 20/td> 1 /1/2
16 705 88.9 508 406.4 469.9 7 616 20 1 5/8
18 785 101.6 565 457 533.4 7 685.8 20 1 7/8
20 855 108 622 508 584.2 7 749.3 20 2
24 1040 139.7 749 610 692.2 7 901.7 20 2 1/2

Class 1500 Weld Neck Flange Dimension

Size ( Inch) OD ( mm ) Flange Thickness (mm) Hub OD Weld Neck OD RF Diameter (mm) RF Height (mm) PCD (mm) No of BoIts BoIt Size (UNC)
1/2 120 22.3 38 21.3 34.9 7 82.6 4 3/4
3/4 130 25.4 44 26.7 42.9 7 88.9 4 3/4
1 150 28.6 52 33.4 50.8 7 101.6 4 7/8
1 1/4 160 28.6 64 42.2 63.5 7 111.1 4 7/8
1 1/2 180 31.8 70 48.3 73 7 123.8 4 1
2 215 38.1 105 60.3 92.1 7 165.1 8 7/8
2 1/2 245 41.3 124 73 104.8 7 190.5 8 1
3 265 47.7 133 88.9 127 7 203.2 8 1 1/8
4 310 54 162 114.3 157.2 7 241.3 8 1 1/4
5 375 73.1 197 141.3 185.7 7 292.1 8 1 1/2
6 395 82.6 229 168.3 215.9 7 317.5 12 1 3/8
8 485 92.1 292 219.1 269.9 7 393.7 12 1 5/8
10 585 108 368 273 323.8 7 482.6 12 1 7/8
12 675 123.9 451 323.8 381 7 571.5 16 2
14 750 133.4 495 355.6 412.8 7 635 16 2 1/4
16 825 146.1 552 406.4 469.9 7 704.8 16 2 1/2
18 915 162 597 457 533.4 7 774.7 16 2 3/4
20 985 177.8 641 508 584.2 7 831.8 16 3
24 1170 203.2 762 610 692.2 7 990.6 16 3 1/2

Class 2500 Weld Neck Flange Dimension

Size ( Inch) OD ( mm ) Flange Thickness (mm) Hub OD Weld Neck OD RF Diameter (mm) RF Height (mm) PCD (mm) No of BoIts BoIt Size (UNC)
1/2 135 30.2 43 21.3 34.9 7 88.9 4 3/4
3/4 140 31.8 51 26.7 42.9 7 95.2 4 3/4
1 160 35 57 33.4 50.8 7 108 4 7/8
1 1/4 185 38.1 73 42.2 63.5 7 130.2 4 1
1 1/2 205 44.5 79 48.3 73 7 146 4 1 1/8
2 235 50.9 95 60.3 92.1 7 171.4 8 1
2 1/2 265 57.2 114 73 104.8 7 196.8 8 1 1/8
3 305 66.7 133 88.9 127 7 228.6 8 1 1/4
4 355 76.2 165 114.3 157.2 7 273 8 1 1/2
5 420 92.1 203 141.3 185.7 7 323.8 8 1 3/4
6 485 108 235 168.3 215.9 7 368.3 8 2
8 550 127 305 219.1 269.9 7 438.2 12 2
10 675 165.1 375 273 323.8 7 539.8 12 2 1/2
12 760 184.2 441 323.8 381 7 619.1 12 2 3/4

Applications of Arrotop Weld Neck Orifice Flange Union

Arrotop Weld Neck Orifice Flange Unions are used in various industrial applications where precise flow measurement is essential. Key applications include:

  • Chemical Processing: Used to measure and control the flow of chemicals, ensuring accurate mixing and reaction rates.
  • Oil and Gas Industry: Essential for measuring the flow of crude oil, natural gas, and refined products in pipelines, ensuring efficient operation and monitoring.
  • Power Generation: Employed in power plants to measure the flow of steam, water, and other fluids, optimizing the efficiency of turbines and boilers.
  • Water Treatment: Used to monitor and control the flow of water and chemicals in treatment plants, ensuring proper purification and distribution.
  • Pharmaceutical Industry: Applied in the production processes to measure the flow of various liquids and gases, ensuring precise dosage and mixture ratios.
  • Food and Beverage Industry: Utilized to measure and control the flow of ingredients and products, maintaining quality and consistency in production processes.

Advantages of Arrotop’s Weld Neck Orifice Flange Union

The Arrotop Weld Neck Orifice Flange Union offers several advantages, making it a preferred choice for precise flow measurement in various industries:

  • Accuracy: Provides highly accurate flow measurement due to the precisely machined orifice plate.
  • Reliability: The robust design and welded connection ensure a secure and leak-free installation, reducing maintenance needs.
  • Durability: Made from high-quality materials, it can withstand high pressure and temperature conditions, making it suitable for demanding industrial environments.
  • Versatility: Can be used with a wide range of fluids, including gases, liquids, and steam, across various industries.
  • Ease of Installation: The weld neck design allows for straightforward installation and alignment with the piping system.
  • Standardization: Available in various standard sizes and pressure ratings, facilitating integration into existing systems.
  • Cost-Effective: Provides a cost-efficient solution for flow measurement compared to more complex flow meters.