Dear All,

This is regarding the CAESAR II & Autopipe result comparison.

I have carried out critical pipe stress analysis using Caesar II.As per client requirement we have to resubmit the report using Autopipe Software.

I have considered Caesar II Translational & Rotational stiffness in Autopipe.

We observed that the Spring Laods are within the range. But for the Guides, Axial stop & Rigid hangers there is huge change in result. Also the thermal movement is different for same geometry.

Please advice.

Regards,
Damanpreet Singh

Verify that the material properties are the same. Next verify that the weight loads are the same in a W only case.

Dear Sir,

As suggested i have changed the below:

1. Translational & Rotational stiffness updated as per Caesar II values.

Translational Stiffness = 0.175127E+15 N/m
Rotational Stiffness = 0.112985E+12 N m/deg

2. Pipe Density updated.

Still there is a change in Results around 50% at Guides/Rigid restraints & Axial stop support points.

Also i need advice for your side Sir.

For Time History analysis, we use Pipenet s/w for fluid transient. The Output(Load v/s Time history) is input in Caesar II dynamic module.

As you know Autopipe having fluid Transient Module. Can we run Fluid transient in Autopipe & input (Load v/s Time history) in Caesar II dynamic module.

Regards,
Damanpreet Singh

If you're getting different results, the models are different somehow.

CAESAR II doesn't care where the input comes from. You can hand CAESAR II a datafile from anywhere, as long as the format matches (i.e. the same as the format of the file from Pipenet).

Sir,

I have run one case in Both Caesar II & Autopipe s/w.

The following observations made during the review.

1. Material Density:- Caesar II uses 7639 kg/m3 for A335 P91 and 7833 kg/m3 A 160 Gr.B. Please guide.

2. Young Modulus, EH = 18915264 kg/cm2 @300 deg C & EC = 20768000 Kg/cm2@ 21 deg C in Caesar II input file.

But as per ASME B31.1 code:- 185 GPA @ 300 deg C.

EH = 1886474.99400917 kg/cm2
EC = 2070023.9123452 Kg/cm2

Note that the Autopipe EC & EH values matching with Code.

There is a difference in values.
I have also attached the files.

Regards,
Damanpreet Singh

Are both models using the same Edition (year) of B31.1?