ASTM A694 F52/F60/F65 Flanges

Scope, Applications & Product Forms

ASTM A694 flanges are forged or rolled pipe flanges suitable for use with high-pressure transmission-service pipes, valves, pumps and other piping components. They can be furnished in carbon steel, low alloy steel or alloy steel. According to its minimum yield strength values, the steel can be classified into 9 grades: F42, F46, F48, F50, F52, F56, F60, F65 and F70. ASTM A694 flanges are readily available for applications in the industrial and transportation fields. They are widely utilized in wellhead and Christmas-tree manifold equipment in oil and gas industry, in which the flanges are designed as end or outlet connectors to valves or other components.

The dimensions of ASTM A694 flanges shall be in accordance with standard specification MSS SP44, ASME B16.47 and ASME B16.5. Although ASTM A694 steel grades are not approved by ASME B16.47 and ASME B16.5, a lot prominent oil and gas companies acquiescence such an use. Such a steel grade can be used as an unlisted material for ASME B16.5 and B16.47, provided that it fully complies with any listed standard specification, including quality control procedures for chemical composition, mechanical properties, heat treatment, etc. Moreover, ASTM A694 flanges can be used in process piping of ASME B31.3, pipeline transportation systems for liquid and slurries of ASME B31.4, gas transmission and distribution piping systems of ASME B31.8.

Chemical Composition Requirements

Element	Composition, % (Heat Analysis)
C	≤0.30
Mn	1.60
P	≤0.025
S	≤0.025
Si	0.15-0.35

*1. Alloying elements including Cu, Ni, Cr, Mo, V, Nb and B shall be reported if any.
*2. No limits apply to above-mentioned elements of A694 forgings furnished in carbon or low alloy steel.
*3. ASTM A694 forgings furnished in alloy steel should be in conformance to ASTM A707 Grade L5.
*4. The carbon equivalent (CE) of ASTM A694 grades shall be calculated by the formula: CE = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15, and shall not exceed 0.42%.

Mechanical Properties

ASTM A694	Yield Strength min. MPa [ksi]	Tensile Strength MPa [ksi]	Elongation in 2", min. %
F42	290 [42]	415 [60]	≤20
F46	315 [46]	415 [60]	≤20
F48	330 [48]	425 [62]	≤20
F50	345 [50]	440 [64]	≤20
F52	360 [52]	455 [66]	≤20
F56	385 [56]	470 [68]	≤20
F60	415 [60]	515 [75]	≤20
F65	450 [65]	530 [77]	≤20
F70	485 [70]	565 [82]	≤18

*Tensile requirements for ASTM A694 forging flanges of all grades: F42, F46, F48, F50, F52, F56, F60, F65 and F70.

Material, Manufacture & Heat Treatment

ASTM A694 flanges shall be made from carbon steel, high-strength low alloy steel or alloy steel, which further shall be made by a fully-deoxidized melting process such as open hearth, electric furnace, or basic oxygen. The flanges shall not be machined directly from plate nor from solid bar stock. The hot forging process shall be performed to develop a wrought structure throughout the flange. All grades of ASTM A694 shall be heat treated. Heat treatment of carbon steel and high-strength low-alloy steel may consist of normalizing, normalizing-and-tempering, or quenching-and-tempering. Heat treatment of alloy steel may consist of normalizing and precipitation heat treatment, or quenching and precipitation heat treatment. The tempering temperature shall be at least 1000°F [540 °C]. The precipitation heat treatment of the alloy steel shall be in the range from 1000°F to 1225°F [540°C to 665°C].

Coating & Packaging

According to customer’s requirements, flanges can be anti-rust oil coating, zinc-plated, hot dipped galvanization or painted in various colors, such as yellow, black, brown and grey. The flanges shall be packaged in sea-worthy firm plywood cases or pallets.