Quels sont les rapports de flexion des coudes à souder bout à bout ?
The bending ratio of a butt welding elbow refers to the ratio between the radius of curvature (R) of the elbow and the diameter (D) of the elbow. This ratio determines the degree of curvature of the elbow and the fluid flow characteristics. Common bending ratios include 1D, 1.5D, 2D, 3D and 5D.
1. 1D Elbow
Definition: The radius of curvature (R) is equal to the pipe diameter (D).
Features: The 1D elbow has the smallest bending radius, so it bends the fastest. It is suitable for occasions with limited space, but due to the sharp bend, the fluid resistance is large.
Application: Usually used inside equipment or in places with tight space, such as when connecting components inside machinery and equipment. Due to the compact space, 1D elbows can better adapt.
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| 45° 1D Elbow | 90° 1D Elbow |
2. 1.5D Elbow
Definition: The radius of curvature (R) is 1.5 times the diameter (D) of the pipe.
Features: 1.5D elbow is the most commonly used standard elbow, balancing fluid resistance and installation space. Suitable for most industrial piping systems.
Application: Widely used in pipeline systems in petroleum, natural gas, chemical industry, water treatment and other industries. For example, in petroleum pipelines, 1.5D elbow is suitable for pipeline layout in most cases to ensure smooth fluid flow.
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| 90° 1.5D Elbow | 45° 1.5D Elbow |
3. 2D Elbow
Definition: The radius of curvature (R) is 2 times the diameter (D) of the pipe.
Features: The bending radius of 2D elbow is moderate, between 1.5D and 3D, and is suitable for pipe systems that require medium bending radius. Compared to 1.5D elbows, 2D elbows provide better fluid flow performance while still maintaining a compact installation space.
Application: Suitable for pipeline systems requiring medium bending radius, such as some medium-pressure and medium-temperature fluid transportation pipelines.
4. 3D Elbow
Definition: The radius of curvature (R) is 3 times the diameter (D) of the pipe.
Features: The 3D elbow has a larger bending radius and a slower degree of bending, which reduces fluid resistance and is suitable for pipeline systems that need to maintain smooth fluid flow.
Application: Usually used in long-distance pipelines and high-flow applications, such as in long-distance natural gas transmission pipelines, 3D elbows can reduce fluid resistance and maintain stable flow.
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| 45° 3D Elbow | 90° 3D Elbow |
5. 5D Elbow
Definition: The radius of curvature (R) is 5 times the diameter (D) of the pipe.
Features: 5D elbow provides a gentler bend, further reducing fluid resistance, and is suitable for long-distance transportation and high-flow pipeline systems.
Application: Suitable for pipeline systems with high requirements on fluid fluidity, such as long-distance oil and gas transmission pipelines, to ensure stable flow and reduce fluid resistance.
