ASME SA350 LF2 Class 1 Forged Carbon Steel Body Flange for Low Temperature Service

ASME SA350 LF2 Class 1 forged carbon steel body flanges are designed for pressure-containing equipment and piping applications that require impact-tested carbon steel materials for low-temperature service.

Manufactured from ASTM A350 LF2 Class 1 forging material, these components are suitable for applications where strength, toughness and material reliability at reduced temperatures are important. The LF2 Class 1 grade is commonly specified for low-temperature piping components in the oil and gas, petrochemical and process industries.

The product shown is marked ASME SA350 LF2 CL.1 BODY FLANGE, with an outside diameter of 1055 mm and an inside diameter of 900 mm. These dimensions identify a large-diameter, ring-shaped flange component. Its final configuration, thickness and connection details should be confirmed against the approved technical specification.

YUHONG supplies forged carbon steel flanges and special flange components according to applicable material standards, dimensional requirements and project specifications.

SA350 LF2 Class 1 is a carbon steel forging grade specified for components requiring notch toughness testing at low temperatures. It is used in pressure-containing applications where resistance to brittle fracture is an important design consideration.

The material provides the mechanical properties required for low-temperature pressure equipment and piping components. Final acceptance is based on the applicable material specification, heat treatment and test results.

Forging provides a formed metal component suitable for large and heavy-duty pressure-containing applications. The forging process and subsequent heat treatment must comply with the applicable material specification and purchase requirements.

• Oil and gas processing equipment
• Low-temperature pressure vessels
• Petrochemical process equipment
• Industrial piping systems
• Pressure-containing equipment
• Large-diameter equipment connections
• Low-temperature process facilities

Final material suitability should be assessed according to design temperature, pressure, loading conditions and applicable construction codes.

Forged body flanges are processed according to their required dimensions and technical specifications. Typical operations may include:

1. Forging of the carbon steel material
2. Heat treatment according to the material specification
3. Machining of the outside and inside diameters
4. Machining of specified faces and connection features
5. Dimensional inspection
6. Material testing and final identification marking

Specific machining details depend on the flange design and approved drawings.

Inspection requirements are determined by ASME SA350, applicable supplementary requirements and the project specification. Typical inspection items include:

• Chemical composition analysis
• Tensile testing
• Charpy V-notch impact testing
• Hardness testing where specified
• Dimensional inspection
• Visual examination
• Ultrasonic testing where required
• Magnetic particle testing where required
• Material identification and traceability

For LF2 Class 1 material, impact testing is an important requirement. Test temperature, sampling and acceptance criteria should be confirmed against the applicable standard edition and purchase order.

Large forged body flanges are packed using export-standard wooden cases, steel supports or securely fixed wooden pallets, depending on their dimensions and weight.

Machined surfaces are protected against impact, moisture and contamination during transportation. Customized packing and shipping arrangements are available according to project requirements.