Hi all. I want caesar to design the spring for my system which has two pumps. T1-Deisgn, T2-minimum design material temp, T3,T4-Hot/cold cases. i used the hanger design control data in the model menu and entered the no. of hanger design operating cases as 2 and selected the ope case 3 in the multiple load case design option. I changed the multiple load case design option to ope case 3 and 4 in the corresponding spreadsheets which is hot at that case. I built 2 cases for hanger travel with t3 and t4 and one weight case for hanger. When i run the analysis and see the hanger text in the output constant spring is selected. I made the results for the hanger cases to be active and checked for the disp in the hanger travel case and the result was ok but when i checked for load in the weight case for hanger it was showing zero load and i think because of this i got constant sproing being selected. When i changed no. of hanger design operating cases as 4 and made 4 cases for hanger travel with t1,t2,t3 and t4 variable spring hanger was selected by caesar which is right. when my hot/cold case is only 2 and i went for the option no. of hanger design operating cases as 2 i didn't get the proper results why i have to specify the option as 4 eventhough i dont use the first two cases in the individual spreadsheet.

If you specify:

- the number of hanger design cases as 1, T1 is used
- the number of hanger design cases as 2, then T1 and T2 are used
- the number of hanger design cases as 3, then T1, T2, and T3 are used


So if you only want T3 and T4 to be used then rearrange your temperature vectors:

Vector OLD New
1 T1 T3
2 T2 T4
3 T3 T1
4 T4 T2

In Caesar II 5.20 where is "Number of hanger design cases"
I can not find in the menu Hanger - Design Data.

Best regards.

Sérgio K.

This is on the "Hanger Run Control" dialog. The toolbar button is on the left side of the window (assuming you haven't moved things around.

What about the load case?
Lets say the temperature is as above, the i select 3 so that T1, T2, and t3 is selected by CAESAR. Do i need to specify again in the load case as below

L1 W+T1+P1 Operating for Hanger Travel on Max. Design condition
L2 W+T2+P1 Operating for Hanger Travel on Min. Design condition
L3 W+T3+P1 Operating for hanger Travel on Hot Cases
L4 W+T4+P1 Operating for Hanger Travel on cold Case

or just do L1 case only?

regards

If you specify that there are multiple hanger design cases, then you also have to specify how the hangers are to be selected, based on these cases: maximum travel, maximum load, average travel, etc.

If you base the selection on case L1 only, there is no point in specifying that you have multiple hanger design cases.

Do these method also applicable for constant effort selection?

Yes, but for a constant effort support all you'll get is the load at that location that has to be carried.

Sorry richard but i don't understand, as for variable hanger Caesar will also calculate the load at that point but the different that there will be cold & hot load for variable spring meanwhile for constant effort cold load will be the same as hot load, what makes different if both spring hanger are the way they take care the movement where for constant effort the movement will be absorb by the spring and the internal force will balance the external force.
I meant that if at preliminary study we have decide to use constant effort because we have a flowline with temperatur 120 C and considerd also the movement of the x mass tree if 100 mm, then do we need to considered multiple thermal case ( as there will be several scenario where all well on, one well off, etc). Do these will efect the way Caesar chhoze the size of constant support or not? Offcourse for vertical displ. The maximum condition still govern for all the scenario, for the load the spring will balance the external load by the internal load of the spring (wxl = fxd), so its looks like these multiple thermal load case do not affected the way Caesar choose the size of the constant effort support?
Correct me if i an wrong, What is your opinion?
Thank you.