SA335 P91 elbow is curved connecting pieces that join straight lengths of pipe, commonly at a 90° or 45° angle, allowing obstructions to be avoided in plumbing, ventilation, welding, and automotive applications.
ASME Elbow P91
ASTM A335 P91 is the part of ASTM A335, The pipe shall be suitable for bending, flanging, and similar forming operations, and for fusion welding.
The steel material shall conform to chemical composition, tensile property, and hardness requirements.
An elbow is a pipe fitting installed between two lengths of pipe or tubing to allow a change of direction, usually a 180° or 90° angle, though 45° elbows are also made. The ends may be machined for butt welding (SW) or socketed welding(SW) etc.
Most elbows are available in short radius or long radius variants. When the two ends differ in size, the fitting is called a reducing elbow or reducer elbow.
Elbows are categorized based on various design features as below:
- Long Radius (LR) Elbow is also called LR elbow – means the radius is 1.5 times the pipe diameter
- Short Radius (SR) Elbow is also called SR elbow, – means the radius is 1.0 times the pipe diameter
- Short radiu 45°Elbow: Short radius 45° elbow changes the direction by 45 degrees.
- Short radius 90°Elbow: Short Radius 90° elbow is same as LR90 except for the measurement between end of elbow to center line is 1 x NPS.
- Short radius 180° Elbow: Short Radius 180° return bend allows complete reversal of flow