What is a 3R elbow?
3R elbow is also commonly known as 3D elbow, and the two refer to the same product. It is a large curvature radius turning pipe fitting in the piping system. Among them, 3R means the bending radius of the elbow centerline is equal to 3 times the nominal pipe diameter (NPS/DN). Compared with conventional 1.5D long radius elbows and 1.0D short radius elbows, it has a gentler and smoother bending radian.
Core Differences Between 3R Elbow and Ordinary Elbow
Conventional elbows are divided into Short Radius SR (1.0D) and Long Radius LR (1.5D), while 3R elbow features a larger curvature radius:
- Lower flow resistance: The bending transition is softer, reducing fluid eddy current and pressure loss;
- Less erosion and wear: Suitable for conveying medium with particles and high flow velocity;
- Strong layout adaptability: The pipeline turns gently, matching long-distance transmission pipelines.
Common Materials and Connection Methods
The mainstream materials of AIFN pipe fitting 3R elbow include 304, 316L stainless steel, carbon steel and alloy steel. It is mostly connected by Butt Weld, complying with ASME B16.9 industry standard, and suitable for high temperature, high pressure and corrosion-resistant working conditions.
Main Application Scenarios
It is widely used in petrochemical, oil and gas long-distance transmission pipelines, power plants, ship pipelines, industrial fluid transmission and other fields, especially suitable for pipeline projects with strict requirements on pressure loss and medium erosion.
Selection Key Points
When purchasing 3R elbow, it is necessary to confirm the angle (common 90°/45°), nominal size, wall thickness grade, material standard and implementation specification, match the design parameters of the project pipeline, and ensure installation compatibility and long-term service stability.
