Bend and elbow are very common pipe fittings used to change the flow direction of the pipe system. Sometimes they are interchangeable, but not the same.


Bent pipe

A bent pipe is a section of a pipe that is bent at an angle to connect two pipes. They can be almost any bend radius and angle. Pipe elbows are usually produced on site to meet the specific needs of thermal induction bending or cold bending. The ANSI / ASME B16.49 standard does not have specific bending radii and angles. Conventional pipe bending radii is 2.5D, 3D, as shown in Figure 5D. It is shown in 7D or 8D, but it can be any other bending radius depending on the design, and the bending angle can be any angle, 5 degrees, 10 degrees, 15 degrees, 90 degrees or any other angle.

Pipe elbows are specific bends that conform to the standard ANSI / ASME B16.9 (or EN 10253 or other pipe fitting standards). Usually, the elbow has a bending radius of 1.5D or 1D (where D represents the nominal diameter of the bend) and is called "long radius elbow (LR elbow)". Or "short radius elbow (SR elbow)". The angle of the elbow is usually 45 degrees or 90 degrees, and sometimes there are custom designed elbows, 30 degrees, 60 degrees, 180 degrees or other angles. People say "All elbows are elbows, but not all elbows are elbows." Very reasonable.