Socket Weld Elbow

Socket Weld Elbow is a type of socket type pipe fitting used for pipeline turning, with socket welding structures at both ends. It is widely used in pipeline systems with small and medium-sized diameters, high pressure, and high sealing requirements. It is a key accessory for changing the flow direction of media in the chemical, petroleum, and power industries.

Structure and Manufacturing

The socket welding elbow is bent at 90 ° or 45 °, and both ends are designed with sockets (circular holes with steps). The inner diameter of the socket is slightly larger than the outer diameter of the pipeline (gap 0.5-1mm), and the depth of the steps ensures accurate positioning of the pipeline after insertion (about one-third of the outer diameter of the pipeline). The materials are mostly carbon steel (A105), stainless steel (316L), and alloy steel pipe (2.25Cr-1Mo), produced through forging process. After forging, internal stress is eliminated through heat treatment to ensure that the mechanical properties of the bent part are consistent with those of the straight pipe section.

Connection and Performance

The connection adopts socket welding: after the pipeline is inserted into the socket, a sealing ring is welded on the outside of the interface, and the height of the welding foot is not less than 1/2 of the pipeline wall thickness. This structure does not require full penetration welding, but can withstand pressures ranging from Class 300 to Class 2500 (5-42MPa), with a working temperature range of -20 ℃ to 450 ℃, and is suitable for high-pressure steam, oil and gas media.

Compared to threaded elbows, its advantages are: low flow resistance (smooth inner wall without threaded protrusions), strong vibration resistance (welding fixation is more stable than threaded connections), and a leakage risk reduction of over 60% in frequent pressure fluctuations.

Applicable scenarios

Direction of feed pipeline for chemical high-pressure reactor (316L material corrosion-resistant);

Lubricating oil pipeline for power plant steam turbine (alloy steel pipe elbow resistant to high temperature of 300 ℃);

The mud conveying branch pipe of the oil drilling platform (A105 elbow can withstand a pressure of 16MPa).