Pocket Guide to Flan..

Figure 2-4. 45-degree elbow, long radius. (Courtesy of Hackney, Inc., a division of
Trinity Industries.)
45-degree Elbows
Figure 2-4 shows a 45-degree long radius elbow.
These elbows are used for partial changes in direction of
the line. The 45-degree elbows are sometimes trimmed
to a lesser degree when required, such as 37 degrees.
180-degree Returns
The return is used for direction changes of 180-de-
grees, thus avoiding the use of two 90-degree elbows.
Figure 2-5 depicts a long and short radius 180-degree re-
turn.
Tees
A tee is a branched connection to the main flow, and
can be either straight or reducing, as shown in Figure
46