Orifice Flanges and Its Specifications

What is Orifice Flange?

Orifice flanges, abbreviated as ORFF, are for metering the volumetric flow rate of liquids and gasses through a pipe. Two orifice flanges are called an orifice flange union. Each flange comes with two pipe taps for measuring the pressure drop of the flow through an orifice plate. Orifice plates do not come with the flanges and are sized based on the requirements of the process. Two jack screws are used to spread the flanges apart in order to change the orifice plate. This flange is normally available in weld neck, slip-on, and threaded flanges. These flanges have a raised face.

Orifice flanges are installed in a straight run of pipe in order to avoid turbulence at the plate. As a rule of thumb, an orifice flange has ten diameters of straight pipe upstream and five diameters of pipe downstream.

When installing the orifice plate flange the pressure taps need to be at the same elevation to each other. The assumption when making the calculation for the orifice plate is that static head of the tubes is the same on both sides of the orifice plate. Pressure taps should not be installed facing down as the taps could become plugged with debris in the line.

Purpose of an Orifice Flange

1. Main Purpose of Orifice Flanges are, they are widely used with orifice meters to measure the flow rate of liquid or gases, flowing through the pipe.

2. An orifice plate, a device measuring the flow of the inner fluid or gas, is secured between two orifice flanges, attached to the pipe.

3. The orifice plate contains a small hole; two pressure tap holes are drilled in each flange which helps in measuring the pressure built inside the pipe.

4. A ‘jack screw’ fitted between the two flanges, it enables to separate the flanges during inspection or replacement process.

Specification of Orifice Flanges

·      Orifice Flanges Size: - 1/2' (15 NB) to 48' (1200NB) DN10~DN5000

·      Orifice Flanges Thickness: - 0.6mm to 20mm

·      Orifice Flanges Grades: - Stainless Steel, Carbon Steel, Duplex Steel, Alloys Steel, Nickel Alloys, Aluminum, Copper Alloys, Monel, Inconel.

Orifice FlangesSpecifications

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

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, Carbonide 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

Orifice Flanges Applications and Uses: -

·      Orifice Flanges used in the Chemicals Industry

·      Orifice Flanges used in Heating

·      Orifice Flanges used in Oil and Gas Industry

·      Orifice Flanges used in Plumbing

·      Orifice Flanges used in Water supply systems

·      Orifice Flanges used in Power Plants Industry

·      Orifice Flanges used in Paper & Pulp Industry

·      Orifice Flanges used in Food Processing Industry

A brief and Detailed Information about Orifice Flanges is shown in this article

Quick links:

·         Different Types of Flanges with its Specifications and Applications

·         Slip-on Flanges benefits and Applications

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