Nozzle Loads on Non-Anchored Vessel

Dear All,

Will there be any nozzle loads due to interconnected piping on a Vessel which is lifted from the ground or only rested (not anchored).??

What will be the approach to analyze the actual nozzle loads coming on that nozzle, as the piping is also moving the vessel with itself (as vessel is not anchored)?

Hello IshaqHashmi

A tank must never at any time lift from the foundation. Should it do so, the tank and the pipework would be severely damaged. That is the reason for investigating the need for anchor bolts.

If we ignore what I have said above, the amount of the lift of the tank off the ground would need to be known, and then a flexibility analysis of the pipework would have to be done, and that is very complicated.

Be very careful to investigate the need for anchor bolts.

Consider it like an in-line filter / strainer etc, which is supported on the adjacent pipe supports and not directly rested on the ground itself.

Will there be any loads on the filter nozzles, considering it in-line and not resting / anchored from the ground?

Can anyone please reply?

Please see
http://65.57.255.42/ubbthreads/ubbthreads.php?ubb=showflat&Number=60362

I've attached few sketches there; in my opinion it is a good example to understand that your in-line component is a part of a piping system that may be subject to bending- for example. How much bending- this depends on the piping configuration and can be calculated by software (Caesar, for example), taking into consideration piping configuration (including restraints) as well the loads (weights, temperature, pressure, seismic, wind) applied to piping configuration.
The fact your in-line component may experience also some movements- for example from a status of system with T1 temperature to other status having T2 temperature, it is of little importance for this discussion; it is important to know the sectional loads (axial and shear forces, bending and torsional moments) in every section of the piping system, in every state of the piping system. The nozzles of your in-line component shall be such sections of interest for you.

Hello IshaqHashmi

I again caution you that a tank should never under any circumstances be allowed to lift from the foundation. It is a violation of the most fundamental engineering and safety principles.

Stresses from external pipe work are an entirely different consideration. CAESAR can give you a good estimate of the loads at any given nozzle. However, it is often the case that tanks must be designed long before the piping system analysis is available. Because tanks generally have a large diameter thin thing wall, there is a fairly low degree of stiffness, and tanks usually survive if the rules of the design code are followed.

Dear ray:

it is not a tank, and i am talking about an in-line piping element (in-line filter in my case) which is supported on the adjacent pipe supports and not on the ground (like rigid element like valves, strainer etc).

Hello IshaqHashmi

Is it possible you could please supply me with a sketch of what you want? Attach it to this thread. Please review the instructions here