A234 WP11 SR 90D Carbon Elbow ASME B16.9 8 Inch SCH 40

A short radius elbow means that the curvature radius of the elbow is twice the diameter of the pipe; also known as D.1 the radius of curvature of the elbow is equal to 1 times the diameter of the tube. usually 90 angles.
intuitively, the short radius elbow is much shorter than the long radius elbow, and the bending radius of the elbow is very short. Long radius elbow is the most commonly used, generally the default is also long radius, high pressure or high flow rate will use a long radius, if the solid pipeline resistance requirements to use a larger radius of the elbow. Short radii are generally used in low pressure fluids or where elbows are limited. If there is no condition limit or no priority in the contract to choose a long radius elbow.