Introduction

In modern industrial pipelines, accurate flow measurement is not optional—it is a fundamental requirement for process safety, cost optimization, and regulatory compliance. Among the many flow measurement devices available, the Orifice Flange Assembly stands out as one of the most reliable and cost-effective solutions.

At NFI, we manufacture orifice flanges with strict adherence to ASME B16.36 and other international standards, ensuring precision, durability, and compatibility with a wide range of pipeline systems.

What is an Orifice Flange?

An Orifice Flange is a specially designed flange used in conjunction with an orifice plate and a differential pressure transmitter. The orifice plate creates a restriction in the pipeline, generating a pressure drop proportional to the flow rate. The flange provides:

Tapping points for differential pressure measurement

Leak-proof sealing for high-pressure operation

Structural support for accurate installation of the orifice plate

Compared with standard weld neck or slip-on flanges, orifice flanges are engineered for metering applications, making them indispensable in energy and process industries.

Standards and Technical Specifications

At NFI, our Orifice Flanges are manufactured in full compliance with global standards:

Design Standards: ASME B16.36, ASME B16.5, EN 1092-1, DIN, JIS, GB/T

Pressure Classes: Class 150 – 2500 (PN2.5 – PN420)

Sizes: DN15 – DN3600 (½″ – 144″)

Materials:

Carbon Steel (A105, ASTM A350 LF2)

Stainless Steel (ASTM A182 F304/F316)

Alloy Steels and Special Grades (P11, P22, P91, Duplex, Inconel, etc.)

Surface Treatment: Rust-preventive oil, galvanization, epoxy coating, or as per client request

Our precision machining ensures concentricity, flatness, and surface roughness that directly influence measurement accuracy and sealing reliability.

Applications of Orifice Flanges

Orifice flanges are widely adopted in critical flow measurement applications where both accuracy and durability are essential:

Oil & Gas Transmission Pipelines – custody transfer and process monitoring

Petrochemical Plants – regulating process flows in refining and chemical production

Power Generation – boiler feedwater, steam flow, and cooling systems

Water Treatment & Distribution – ensuring accurate resource allocation

Industrial Process Control – supporting automation and digital monitoring systems

By integrating with modern SCADA and DCS systems, orifice flange assemblies provide real-time data that enhances operational efficiency and reduces downtime.

Why Choose NFI as Your Orifice Flange Manufacturer?

Hot Forging Expertise – guarantees superior grain structure and mechanical strength

Strict Quality Control – each flange is tested for dimensional accuracy, pressure resistance, and sealing performance

Customization Capability – tailor-made solutions for material grades, pressure ratings, and tapping locations

Global Compliance – full documentation support (MTC, EN 10204 3.1/3.2, NACE MR0175)

International Supply Chain – proven track record in supplying to oil majors, EPC contractors, and distributors worldwide

When selecting an orifice flange, accuracy, durability, and compliance should be the key factors—and this is where NFI adds value beyond manufacturing.

Conclusion

As industries demand more accurate and reliable flow measurement, the orifice flange assembly remains a proven and cost-effective choice. With compliance to ASME B16.36 and precision hot-forged construction, NFI orifice flanges provide unmatched performance across oil & gas, power, water, and chemical sectors.

For technical consultations, custom designs, or quotations, please visit our official product page:
👉 NFI Orifice Flange Details