The function of an elbow
Its function is to change direction of flow in a piping system. Elbows are split into three groups, which define the distance over which they change direction, which is expressed as a function of the distance from the centre line of one end to the opposite face. This is known as the centre to face distance and is equivalent to the radius through which is the elbow is bent. 90 degree elbow, also called “90 bends or 90 elbows”, are manufactured as SR (Short Radius) elbows andLR (Long Radius) elbows.
What is the difference between LR and SR elbow?
SR (Short Radius) elbows have a Center-to-Face dimension of 1.0 X diameter and are typically used in tight areas where clearances are an issue .LR (Long Radius) elbows have a Center-to-Face dimension of 1.5 X diameter and are the more common type and used when space is available and flow is more critical. This is a fitting device which is bent in such a way to produce 90 degree change in the direction of flow of the content in the pipe.