ASTM A694 F65 Weld Neck Flange | WNRF & WNRTJ

ASTM A694 F65 Weld Neck Flanges are high-yield forged steel flanges designed for high-pressure transmission piping systems, including oil and gas pipelines, compressor stations, manifolds and other critical pressure applications.

F65 provides a minimum yield strength of 65 ksi / 450 MPa, making it suitable for high-strength pipeline systems where conventional carbon steel flange materials may not provide sufficient strength.

Available configurations include Weld Neck Raised Face (WNRF) and Weld Neck Ring Type Joint (WNRTJ) flanges manufactured to ASME B16.5, ASME B16.47 or MSS SP-44 as specified.

ASTM A694 F65 Weld Neck Flange Overview

What Is ASTM A694 F65?

ASTM A694-A694M  covers carbon and alloy steel forgings for flanges, fittings, valves and other components used with high-strength transmission-service pipe.

Grade F65 is identified primarily by its 65 ksi minimum yield strength.

Unlike a single fixed alloy designation, F65 can be produced using suitable carbon steel, high-strength low-alloy steel or alloy steel chemistry capable of meeting the required mechanical properties after heat treatment.

Typical chemical limits include:

Additional alloying elements are reported as applicable.

Mechanical Properties

Impact testing is not automatically required for every F65 flange. Charpy impact requirements should be specified separately when required by the project, design temperature or piping specification.

F65 Weld Neck Raised Face Flange

A694 F65 WNRF Flanges are commonly used in high-pressure pipeline connections where a raised-face gasketed joint is specified.

The long tapered hub provides a gradual transition between the flange and pipe, reducing localized stress concentration compared with flange types without a welding neck.

A typical order description is:

ASTM A694 F65 Weld Neck Flange, NPS 16″, Class 600, RF, Sch STD Bore, ASME B16.5

F65 Weld Neck RTJ Flange

ASTM A694 F65 WNRTJ Flanges are frequently used in higher-pressure piping systems.

The Ring Type Joint facing uses a metallic ring gasket installed in machined grooves between mating flanges.

Typical applications include:

• High-pressure pipelines
• Compressor stations
• Oil and gas facilities
• Offshore piping
• Manifold systems
• High-pressure process piping

Typical order:

ASTM A694 F65 WNRTJ Flange, NPS 8″, Class 1500, Sch 160 Bore, ASME B16.5

RTJ groove number and gasket requirements should be confirmed from the applicable flange standard and project specification.

ASME B16.5 and ASME B16.47 F65 Flanges

ASTM A694 defines the material requirements, while flange dimensions are specified separately.

ASME B16.5

Used for standard pipe flange sizes up to NPS 24, subject to the applicable Class and size combination.

Common pressure classes include:

Class 150, 300, 400, 600, 900, 1500 and 2500

ASME B16.47

Used for large-diameter steel flanges from NPS 26 through NPS 60.

Available configurations include:

• Series A
• Series B

with applicable pressure classes from Class 75 through Class 900.

MSS SP-44

MSS SP-44 Steel Pipeline Flanges is also widely specified for high-strength pipeline applications and is particularly relevant to ASTM A694 F65 material.

F65 Flanges for API 5L X65 Pipeline Systems

A common high-strength pipeline material combination is:

These grades are frequently selected for pipeline systems requiring similar high-yield-strength levels.

However, API 5L X65, ASTM A694 F65 and ASTM A860 WPHY65 are separate product specifications and are not directly interchangeable material grades.

Each component must meet its own applicable material and product standard.

NACE and Sour-Service F65 Flanges

ASTM A694 F65 Weld Neck Flanges can be supplied for sour-service projects where NACE MR0175 / ISO 15156 requirements are specified.

Sour-service suitability should be evaluated against the actual project requirements, including:

• Material chemistry
• Heat-treatment condition
• Hardness
• Service environment
• H₂S exposure
• Welding requirements

ASTM A694 F65 designation alone does not automatically establish NACE compliance.

HIC Tested ASTM A694 F65 Flanges

Hydrogen-Induced Cracking testing can be performed to NACE TM0284 when specified.

HIC testing is an additional project requirement rather than a standard ASTM A694 requirement.

Acceptance criteria should be clearly stated in the purchase specification.

Inspection and Certification

ASTM A694 F65 Weld Neck Flanges can be supplied with:

• EN 10204 Type 3.1 MTC
• EN 10204 Type 3.2 when specified
• Chemical Analysis
• Mechanical Testing
• Hardness Testing
• Charpy Impact Testing when specified
• UT
• MT
• HIC Testing when specified
• PMI when required
• Dimensional Inspection
• Third-Party Inspection
• Full Heat-Number Traceability

How to Order ASTM A694 F65 Weld Neck Flanges

A complete RFQ should specify:

• ASTM A694 F65
• Weld Neck Flange
• NPS
• Pressure Class
• RF or RTJ
• Bore / matching pipe wall thickness
• ASME or MSS standard
• Quantity
• NACE requirement if applicable
• HIC or impact testing if required
• Certification and inspection requirements

Example

ASTM A694 F65 Weld Neck Flange, NPS 12″, Class 900, RTJ, Sch 120 Bore, ASME B16.5, NACE MR0175 / ISO 15156 and HIC testing as specified

ASTM A694 F65 Weld Neck Flange Supplier

We manufacture and supply ASTM A694 F65 Weld Neck Flanges for high-pressure pipeline and process applications.

Available products include WNRF and WNRTJ flanges to ASME B16.5, ASME B16.47 and MSS SP-44, with project-specific NACE, HIC, impact testing and third-party inspection available when required.