hi

i am new to pipe stress and want to know more about ancroing of nozzle means modeling of equipment etc can anybody help

Most equipment that we are interested in consists of a nozzle and an anchor or fixed point of some sort. It could be a pump, compressor, pressure vessel, heat exchanger, tank or similar. The nozzle is clearly where piping of interest attaches, the anchor may be a bolted foundation for a pump, or the fixed end saddle in a pressure vessel for example.

Modelling such equipment means simulating its effect on connected piping and thus including it in a stress analysis.

We may be concerned about equipment thermal expansion, or as a source of vibration in connected pipe for instance. Equally we may want to know how flexible the equipment is, or what loads the piping applies to it.

thanks moverz,

can u tell me how we do it in caesar and procedure

Look at the examples provided with the software.

There is a gentleman who has provided many comments on this CAESAR II forum whose name is Ed Klein. Ed has a tagline on his posts that says "All the World is a Spring".

For many years I read Ed's postings, and thought that Ed was a romantic (visions of babbling brooks, birds in meadows etc.....)

However it finally dawned on me that he was referring to the world that we pipe stress engineers live in. The world consists of one massive composite spring, but each of these springs has a different stiffness.

So the simplest pipe stress model for a pipe connected to a vessel would have the vessel modelled as an anchor - which is an infinitely stiff spring.

The next level of complexity might have the nozzle modelled as a short piece of pipe which is connected to an anchor. So a pipe connected to a reasonably stiff spring connected to an infinitely stiff spring.

Another level up might have the vessel modelled as a piece of large diameter pipe. So you have a pipe connected to a reasonably stiff spring which is connected to another reasonably stiff spring (vessel shell) which is connected to an infinitely stiff spring (the foundation). You might also choose to model the local shell stiffness which is another "spring".

Your choice of which model to use depends on the nature of your problem. If the simplest model is code compliant and satisfies your nozzle loading requirements, then you probably don't need to do anything more.

On the other hand if the nozzle is overloaded, then modelling its true stiffness is likely to reduce the nozzle loads.

my problem is that i have task to model submercible pump and its piping as i new to caesar ,so i couldn't get the problem correctly plz any one help

Hi Ava,

What is your e-maill address. i have some presentation regrding the modelling of equipment and pump .All basics stuff...

Regrds,

akula

hi kumar

my email id is avai_mech@yahoo.co.in , plz send the matrl it will be very helpfull tahnks in advance


ava

thanku very much kumar for your stuff

Hi Kumar

may I ask if you have some matrl's for Buckling allowables on pipes
thank you in advance
.if you have, send to my email albert01diega@gmail.com

thanking much

hai kumar/ava,

can you send it to gowthamj@rocketmail.com

thanks in advance