ASME B16.5 Class 150/300 Forged Steel Socket Weld Flange

CARBON STEEL: ASTM A105 / A105N, ASTM A350 LF2 / LF3, ASTM A694 F42 / 46 / 56 / 60 / 65

STAINLESS STEEL: ASTM A182 F304/304L/304H, 316/316L, 310S, 317, 347, 904L, ASTM A182 F51, F53, F44

ALLOY STEEL: ASTM A182 F11 / 12 / 5 / 9 / 91 / 92

Sealing Face:  RF, FF, FTJ

Petrochemical Industry
- Used in refining and chemical pipeline systems to connect reactors, heat exchangers, valves, and other equipment, meeting the transmission requirements for high-pressure, high-temperature, and corrosive media.
- Example: In petroleum cracking units, socket weld flanges ensure stable connections for high-temperature oil and gas pipelines.

Natural Gas Transportation and Storage
- Suitable for scenarios such as natural gas long-distance transmission pipelines, compressor stations, and gas storage facilities, connecting pipelines with valves, instruments, and other components to ensure the safety of high-pressure gas transportation.

Power Industry (Thermal and Nuclear Power)
- Used in steam pipelines, cooling water systems, etc., in power plants to connect boilers, steam turbines, and other equipment, withstanding high-temperature and high-pressure working conditions.
- In nuclear power plants, socket weld flanges are also commonly used in safety-class pipeline systems to ensure tightness and seismic performance.

Marine and Offshore Engineering
- Applied in scenarios such as seawater pipelines, fuel systems, and compressed air pipelines on ships, capable of withstanding vibration, impact, and corrosive environments. The structure of socket weld flanges reduces leakage risks.
- Also frequently used for connecting pipelines in offshore platform oil and gas extraction systems.

Pharmaceutical and Food Processing
- Used in pipeline systems with high cleanliness requirements (e.g., purified water and steam pipelines in pharmaceutical workshops). Socket weld flanges have smooth inner walls, facilitating cleaning and complying with hygiene standards.

Heating and Refrigeration Systems
- Used in high-pressure steam pipelines for central heating and chilled water pipelines in central air conditioning systems, requiring reliable connections to withstand thermal expansion/contraction and pressure fluctuations.

Mechanical Equipment Manufacturing
- Used for connecting inlet and outlet pipelines of large mechanical equipment (e.g., compressors, pump units) to ensure no leakage and resistance to vibration during power transmission.

1. High Connection Strength and Reliable Structure

Large Welding Area: The flange and pipeline are welded through a socket-type interface with a fillet weld, providing a large welding contact area that can withstand high pressure and mechanical loads.

Good Vibration Resistance: The welded structure is firm, suitable for scenarios where the pipeline system is subject to vibration or impact (such as connections for compressors and pumps), and is not easily loosened by external forces.

2. Easy Installation with Low Alignment Requirements

No Complex Alignment Needed: The pipeline can be welded after being inserted into the socket of the flange, eliminating the need for strict alignment of pipe ends as required by butt-weld flanges, reducing installation difficulty and saving time costs.

Suitable for Space-Constrained Scenarios: It offers higher installation efficiency in narrow or hard-to-reach areas (such as dense pipeline layouts).

3. Excellent Sealing Performance and Reduced Leakage Risk

Tight Welded Interface: A continuous seal is formed after the fillet weld is fully filled. When used with flange gaskets, it effectively prevents medium leakage, making it suitable for high-pressure, high-temperature, or toxic/hazardous medium pipeline systems.

No Weld Protrusion into Pipeline Inner Wall: After the pipeline is inserted into the flange, the inner walls are flush, and the weld is located on the outer side of the flange, avoiding medium impact on the weld during flow and reducing wear and leakage hazards.

4. Low Cost and Good Economy

Less Material Consumption: Compared with butt-weld flanges, socket weld flanges have a shorter neck, less material usage, and lower manufacturing costs.

Low Maintenance Cost: The simple structure and reliable sealing require less daily maintenance, making it suitable for pipeline systems that need long-term stable operation.

5. Clear Application Scope and Matching Specific Needs

Preferred for Small-Bore Pipelines: Commonly used in pipelines with a nominal diameter ≤ DN80 (NPS 3"), as the thinner wall thickness of small-bore pipelines avoids burn-through risks during butt welding.

Prevention of Medium Retention: The flush inner wall design reduces retention points of the medium in the pipeline, suitable for media prone to precipitation or scaling (such as slurry and high-viscosity liquids).