how to consider friction in spring support

Posted by: NAG

how to consider friction in spring support - 10/17/19 09:27 PM

Hi experts,

Please guide me how to consider friction for spring support in Caesar ii software input.
Posted by: Sigma

Re: how to consider friction in spring support - 10/17/19 10:43 PM

Please refer to CAESAR II Applications Guide (Section 4) for Modeling Spring Cans with Friction.
Posted by: NAG

Re: how to consider friction in spring support - 10/19/19 01:30 AM

hi sigma,

Thanks for the reference.

But in the application guide
From pipe center to till spring node rigid. end of the rigid they mentioned X,Z restraint. for what reason XZ restraint on that node.

If we consider XZ hanger does not move right
horizontally.
Posted by: NAG

Re: how to consider friction in spring support - 10/19/19 05:13 AM

see the attached image.
5-10 rigid element - it is clear trunnion pipe leg+ radius of pipe.

10 c node 15
restraint x,z- not clear to me . For what reason this restraint.

10 hanger with c node 15- it is clear.

Why +Y at node 20 normally trunnion not fixed to spring top load flange. Actually friction occurs that point.

But here it is fixing point btn steel & spring box base plate.Is this correct approach.
Posted by: Sigma

Re: how to consider friction in spring support - 10/23/19 02:02 AM

Node 10 C-node 15 is required to generate & transfer the frictional force from Spring Can bottom to bottom of shoe or trunnion.
Also, Please refer the statement at bottom of sketch - Alternatively, element 15-20 can be omitted with the +Y restraint (with friction) placed directly on node 15.
Once done, please review the output to ensure you have understood this correctly.
Posted by: joeseagle

Re: how to consider friction in spring support - 11/20/19 07:33 AM

I'm curious why this feature can't be programmed into Caesar to automatically apply friction to spring cans?

This manual process seems quite tedious for something that would theoretically need to be applied to every single spring can application.
Posted by: Richard Ay

Re: how to consider friction in spring support - 11/20/19 06:20 PM

The development of a "wizard" to model friction under a spring support is on the development list - it's just a matter of priorities. If this capability is a priority for you, please file an SR. The more SRs a request has, the more weight it has in our decision making process.

Note that the "wizard" would have to generate the same elements and restraints as shown in the documentation.
Posted by: NAG

Re: how to consider friction in spring support - 11/20/19 10:18 PM

HI RECHARD,

I ALREADY FILE THE SERVICE TICKET FOR THE DEVELOPMENT.