Recent content by usecheijk

Hi!, In a flexibility pipe analysis, how to modeling a nozzle connected to a pressure vessel at the end of a pipe?, How to modeling the structural stiffness of the vessel? Such stiffness could be replaced by any flexible boundary condition at nozzle? Thanks in advance, Jack.

Hi everyone, What means ">360°" in table 9B.14 of API 579/FFS-1 2016? (see image below): Thanks in advance. Jack

Thank you BJI. Very crearly.

Hi everyone I have doubt about meaning of local failure criteria addressed in API 579. Is it a material rupture criteria? Why no simply to compare the local platic equivalent strain with the failure strain measured from tension test? Thanks in advance Jack

Hi there! I have a pressure load spectra with pmax = 1500 psi and pmin=0 psi. When I using rainflow algorithm for cycle counting, I obtain both mean and range value blocks higher than pmax. ¿Is this possible? Thanks in advance, Jack

I have a doubt about MAWOP calculation in FFS-III burst analyisis of pipelines under internal pressure, considering corrosion metal loss. Most of MAWOP FEA calculations reported in the literature considers full yielding of the remanent material in metal loss zone as failure criteria. Thus, the...

Thanks to everyone for you answers. Jason8zhu, what FAC and AC means?

Hi I want to perform a fatigue crack growth analysis for a thin walled fractured vertical mast under win loads. ¿How can I perform this kind of analysis if spectral win load (aerodynamic pressure load over mast) is provided?. I have experience with crack propagation analysis under quasi-static...

Dear Dhengr I only want to know if hole-drilling method is possible in apressurized lines and how dangerous it can be. I thought it was risky, but these examples show could be not.

Thank you for your answers. Yes!, hole-drilling method for residual stress in live pipelines. Check these cases: http://sem-proceedings.com/rss4/sem.org-4th-Residual-Stress-Summit-Albertazzi-Hole-Drilling-Evaluation-Residual-Stresses-Buried.pdf...

Thanks to your for your answers. Yes! hole-drilling method in live pipelines!. Check these cases...

Can be used the hole-drilling method to measure residual stress in buried pipelines (pressurized pipelines)? ¿how dangerous it can be? Thanks, Jack

Thanks to all for your answers, But the question is: ¿can the S-N curves be used in fatigue life analysis of dents where residual stresses and plastic deformation are present?, i.e. ¿S-N curve for this material before and after the dent, is the same? Thanks, Jack

Hi. Deformational processes, like a dent (15% deep), in a pipeline (API 5LX65) changes the S-N fatigue curve of the deformed material? Thanks

Yes, however Kf defined in table B1.10 and B1.11 is only for welds. ¿What happen with other fatigue reduction factors Ka,Kb,Kc, etc. (Se = Ka.Kb.Kc...Se') commonly used in fatigue analysis?. Jack