Read about START-PROF pipe stress analysis software
Insert a node on the bend edge and insert a resting support
To take into account the support thermal expansion, just add the upward displacement of the resting support equal to the value of thermal expansion. To improve accuracy, add rigid element (with temperature expansion) with length equal to the radius of the bend, and after it add trunnion pipe.
Advanced model automatically created when using Trunnion on the bend element
To model a trunnion - insert a node on the bend edge
Insert a pipe (trunnion) in this node with zero pressure and zero fluid weight. Don't insert a tee into intersection point. And insert a support at the trunnion's end. To improve accuracy, add a rigid element with length equal to band radius and add trunnion next to it.
The approximate temperature drop per length of trunnion is
For non insulated pipe 40°C per 1 inch (25 mm)
For insulated pipe 4°C per 1 inch (25 mm)
Sometimes used 1/3 of operating temperature for trunnion
It could be modeled the same as shown at example 1. Here we will show the another way of modeling.
Insert a node on any point along the bend axis curve.
Additional node is created and bend splitted into two parts. The angle on each part should be set as 90 degree. It means that these two bends are parts of single 90 degree bend. This angle is used for flexibility k-factor calculation.
After that the rigid element should be added with a hanger on it's end. The weight of rigid element should be a zero. Don't insert a tee.
