In CII, the vertical load from Restrainted Weight Case is HOT LOAD. How should I do if I want the load from Restrainted Weight Case is COLD LOAD ?

Which case is better for Spring Hanger design (HOT LOAD or COLD LOAD)?

Thanks.

Assuming you're running Version 5.20, just check the checkbox on the "Hanger Dialog" for "Cold Load Design". If you're running a version earlier than 5.20, read the "help text" on the "hanger table number" - it will tell you how to do this.

Assuming your system is operating most of the time, that is the condition you want the springs balanced for. Therefore "hot load" is the perferred design condition for the springs. (In my opinion, you need a really good reason to pick "cold load" design.)

Hi Richard,

The word "balance" means the spring hanger will take the DEAD LOAD in operating condition. Is it right? Can you explain more about this point ?

In my opinion,

- With HOT LOAD design, if we want spring hanger takes dead load EXACTLY then we must know the "travel" from Temperature EXACTLY. Is this "travel" true in operating condition (reality)? And I think we maybe need a lager size than in COLD LOAD design.

- With COLD LOAD design, the spring hanger will take dead load in INSTALL CONDITION. When the system in operation, HOT LOAD will no longer take dead load. So, the spring size is smaller.

I assume that other supports around the spring hanger have capability to take the difference load between CL and HL (in CL design).

The attachment illustrates my ideal.

We default to "balancing" the hot or operating load rather than cold/installed load because you typically want to control the operating load. Our focus is on a proper spring for the operating load not on the smallest acceptable spring size.
CAESAR II selects a spring to suit your design criteria. It's up to you to accept or change that selection.

@VanHa:
There is a nice paper from LC Peng about hot and cold spring design. You can download it from his website as extra reference.