How to model a insulated pipe support like this in AutoPIPE?
First is to understand the various types of supports available in AutoPIPE and how to best combine them to reflect this type of support. Keep in mind the way that this support functions:
1. The pipe is fist supported by the insulation between the pipe and the actual Steel support. This insulation has a different support spring rate and friction than the steel support.
2. The insulation is then held in place by the actual steel support. The steel support has its own support spring rate and friction.
3. Can we assume that the Insulated Steel support is attached to rigid ground or model it attach to additional Steel beams that are then supported by the ground.
As one can see there are 3 stages to this support approach. Let us build this support starting from the ground with the following assumptions:
a. Insulated support is connected to ground, no elaborate support frame/structure to be considered.
b. Insulation thickness is 3 inches thick
Step #1: Give the following model:
The Insulated support will span from A02 - A06
Step #2: Insert the steel beam that is the backbone of the insulated support, from M01 to M03 (assign a beam property in close approximation of the insulated support steel or rigidity).
Step #3: Point M2 is assumed to be connected to ground. Insert a short vertical beam and add an anchor at the end.
Step #4: Insert the steel supporting the insulation.
In this example, the insulated support spans from A02 - A06.
a. Make A02 the active point.
b. Insert a guide support, connected to M1, with gap = 3" in all directions, Support Stiffness = Rigid, and Friction = your calculations.
c. Repeat steps A & B at node point A06 connecting to M3
Step #5: Insert insulation that is supporting the pipe.
What ever insulation used will have a manufacture reference for support force. Convert this to a spring rate and add to a support
a. Make A02 the current node point.
b. Insert a guide support, connected to M1, with gap = 0" in all directions, Support Stiffness and Friction = your calculations.
c. Repeat steps A & B at node point A06 connecting to M3.
Note: the 2nd support at node A02 and A06 are highlighted. As can be seen above, the are 2 supports at these points, One is colored Red, the Second is colored Green.
Review the output report for the intermediate support locations (ex. A03 - A04 - A05). If these nod points are moving in an direction more so then the ends (ex. A02 & A06. Then consider one of the following:
a. Insert rigid properties over range (ex. A02 to A06) with both options enabled.
b. Insert additional intermediate supports as performed above.
In this modeling technique, the 1st set of guide supports at A02 and A06 has the same properties as the insulation. if a force strong enough to crush the insulation is applied, the pipe will be allowed to move until it reaches the gap distance set by the 2nd set of guide supports at A02 and A06. All 4 of these supports are connected to the horizontal beam M1-M2-M3. These set of beams represent the structural integrity of the insulated support mentioned in the manufacture literature. Finally, all this is connected by a short beam (M2 - M4) to ground.
Note, overall modeling assembly of all the supports with regards to weight, friction, rigidity, etc. totals should be as close to that of the actual insulated support manufacture literature. Be warned about any double counting errors in calculations and modeling.
Different Types of Supports In AutoPIPE?
Guide support modeling - WIKI posting
Bentley AutoPIPE