1. Main features
High pressure tolerance: The design pressure is usually ≥ 15MPa, and can reach up to 100MPa or more. The material is mostly high-strength alloy steel or stainless steel.
Flexible and adjustable: By rotating structures such as ball joints and threaded connections, the angle can be adjusted from 5 ° to 30 ° to adapt to pipeline installation errors or thermal expansion and contraction.
Strong sealing: using metal sealing rings, O-rings or corrugated pipe structures to ensure no leakage under high pressure.
Corrosion resistance/high temperature: Depending on the working conditions, nickel plating, spray coating, or special alloy (such as Inconel) materials can be selected.
2. Typical structural types
Ball joint elbow: It rotates through an internal spherical structure and is suitable for multi-directional adjustment.
Threaded rotating elbow: connected by threads at both ends, rotatable in the middle for easy installation.
Flange rotating elbow: equipped with a flange plate, the angle can be adjusted after bolt fixation.
Bellows compensation type: Integrated bellows, absorbing vibration and displacement.
3. Key parameters for selection
Parameter example values/requirements
Pressure rating 15MPa/30MPa/70MPa
Diameter (DN) 50mm~300mm
Temperature range -46 ℃~450 ℃ (low temperature requires cryogenic treatment)
Connection method: API 6A flange, NPT thread, welded end
Compliant with API 16C and ASME B16.11 standards
4. Installation precautions
Pre tightening force control: Bolts should be tightened in the order of torque to avoid uneven sealing surfaces.
Angle compensation: Leave 5% to 10% adjustment margin after installation to cope with thermal displacement.
Flow direction marking: Some designs have directionality (such as globe valve assembly) and need to be installed according to the arrows.
Pressure test: A static water pressure test at 1.5 times the working pressure is required.
