Elbows 45° - 90° - 180° LR/SR

The function of a elbow is to change direction or flow in a piping system. By default, there are 5 opportunities, the 45°, 90° and 180° elbows, all three in the "long radius" version, and in addition the 90° and 180° elbows both in the "short radius" version.

Long and Short Radius

Elbows are split into two groups which define the distance over which they change direction; the center line of one end to the opposite face. This is known as the "center to face" distance and is equivalent to the radius through which the elbow is bent.
The center to face distance for a "long" radius elbow, abbreviated LR always is "1½ x Nominal Pipe Size (NPS) (1½D)", while the center to face distance for a "short" radius elbow, abbreviated SR even is to nominal pipe size.

Here below, for example, you will find the
center to face distance of NPS 2 elbows
(the A distance on the image)

1. 90°-LR : = 1½ x 2(NPS) x 25.4 A=76.2 mm

2. 180°-LR : = 2 times the 90° LR elbow A=152.4 mm

3. 90°-SR : = 2(NPS) x 25.4 A=50.8 mm

4. 180°-SR : = 2 times the 90° SR elbow A=101.6 mm

3D elbows as an example, are calculated with:
3(D) x 2(NPS) x 25.4

45° Elbow

The function of a 45° elbow is the same as a 90° elbow, but the measurement of dimensions is different to that of the 90° elbow.

The radius of a 45° elbow is the same as the radius of the 90° LR (1½D). However, the center to face dimension is not equivalent to the radius as in 90° LR elbows. This is measured from each face to the point of intersection of the center lines perpendicular to each other, distances B on the image. This is due to the smaller degree of bend. Short radius 45° elbows are not available.

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