Carbon steel elbow is divided into long radius elbow and short radius elbow. Long radius elbow means that the curvature radius of elbow is 1.5 times the pipe diameter. D represents the elbow’s diameter. Short radius elbow means that the radius of curvature of the elbow is equal to the diameter of the pipe. The curvature radius more than 1.5 times is called bend.
Long radius eblow is more commonly used in pipeline. While short radius less used, due to their special structure.Telling from appearance, the short radius elbow is much shorter than the long radius elbow and the bending radius of the elbow is rapid. Compared with the short radius elbow, the long radius elbow has more uniform bending radian and higher compression resistance.Butt welding elbow is generally a long radius elbow.Generally in high pressure or high velocity of the place, long radius is used. When there are strict solid pipeline resistance requirements, a larger radius of the elbow may be applied. Short radius is generally used in low-pressure fluid or where installation in a limited place. Long radius elbow shall be preferred unless specially mentioned.
Uses of 1.5D elbow:
1. To reduce pipeline stress and increase the flexibility of pipeline, common in thermal oil pipeline.
2. To alleviate the pressure drop of the pipeline.
3. To reduce the dynamic pulse force of the fluid on the pipeline, as well as the dynamic load of the fluid.
Uses of 1D elbow:
1. No special pressure drop requirements, no special requirements for fluid flow.
2. Cases when there is outer shell, the inner pipe is 1.5D elbow and the outer pipe is 1D elbow, to ensure the inner pipe is smoothly inserted into the outer pipe and lower the construction difficulty.
3. To reduce the vibration of the pipeline and increase the rigidity of the whole pipeline.
Post time: Mar-22-2021