Applies To
Product(s):	AutoPIPE
Version(s):	All
Area:	Tee
Original Author:	Bentley Technical Support Group
Date Logged & Current Version	Aug. 2016 10.01.00.09

Problem:

How are local axes defined at a tee?

For example, does the in-plane SIF get applied to Mz or My or does it depend on the orientation of the branch?

Solution:

See the following AutoPIPE online help section for details on determining the local axis of any straight pipe.

Help > Contents> Contents Tab> Reference Information> Results Interpretation >

A. Pipe Displacements

B. Pipe Forces and Moments: Global Option

C. Straight Pipe Forces and Moments: Local Option.

After reading these sections you will come to realize that a tee branch node point can have up to 3 faces where results are calculated:

1. Header +ve side.

2. Header -ve side.

3. Branch +ve side.

To answer the question above, does the in-plane SIF get applied to Mz or My or does it depend on the orientation of the branch?

Answer,

independent of local or global axis. the axis of the header pipe and the axis of the branch pipe create a plane. This plane would be considered the In-Plane. A plane that is perpendicular to the In-Plane is called the Out-of-Plane. As indicated below:

As the branch direction rotates around the header piping so do both the In-Plane and Out-of-Plane. When applying a Tee In-Plane SIF and Out-of-Plane SIF they are applied to the corresponding planes as indicated above.

Note: the local axis of the header piping is not affected by the Tee's branch direction.

01. How are local axes defined at a tee in AutoPIPE?

Problem:

Solution:

See Also