Can we model user defined components in caesarII?
There are some defined components like Bend, Rigid etc. But do we have any option through which we can model user defined component. E.g I have one component Tap component. How could I model it into Caesar II? Or how can I find equivalent component in caesarII?

CAESAR II utilizes a "3D beam element" for everything. Conseptually, this is an infinitely thin stick, with properties (E, D, t, denstiy, alpha, etc). If what you're trying to model can not be simulated with this "3D beam element", then you can't achieve the proper analysis or results.

Why do you want to model the tap?

Actually I'm generating a cii from the design which contains the components. I have tap component in design. Now I want to know, to which section in cii, this tap or any user defined component should get reported so that it will be viewed in caesar II? So I want to know, if I will have to model it directly in caesar II, then which type I would have chosen for this?

Priti,

The standard piping components include fitting components like bends, elbows, tees , reducers, weldolets, sweepolet, ( all of which are difined in B31.3 ) etc, all of which can be modelled in Caesar II either by use of bend option or by the use of SIF option.Since component like latrolet is not defined in B31.3, you can use the SIF for Boney-Forge to do so.Other than that even thredolets and sockolets can also be modelled in Caesar II using threaded /socket welded option in SIF.Similarly for Valves, Flanges etc. you have the rigid option.That completes the list of conventional fittings.

I personally feel that if you really have such a non standard fitting ( tap) think whether that line really requires stress analysis. If so, try out the rigid option which will simulate the effect ( conservatively ) for than non standard component.You can give some wt. for the rigid element or leave the wt. blank if it is not significant.

Anindya Bhattacharya

Stress Analyst

Bechtel Corporation.

Priti,

The first thing you have to understand is how the software simulates th
effect of component defined in the input.
When you are defining a component it will affect the weight and the
stiffness of the system.

Coming to stiffness, if you specify the component as rigid, it will consider
it as a pipe element which is 10 times more thick than the connected
pipe.This is conservative from the standpoint of displacement induced
loads.However a small component's thickness is not likely to substantially
affect the global stiffness matrix.

The wt. part will govern the primary stresses and the permitted
deflection.So if you know the wt. you better give the correct input or else
give some higher wt. to make it more conservative. However if your component
size is not significant enough, you can even omit the wt. and leave it
blank.

The contribution in stiffness and wt., can be of significance for very
critical systems( high temp., rigid systems) otherwise consideration ofa
simple pipe element for that component is good enough.

I have given you both the options.Now use your engineering judgement to see
which one you require.