Good morning, Please, I need to

[ifran31]

Good morning,

Please, I need to know what percentage of falling thickness it is said that pipes must be changed.

Piping case (process and power),

Regds
R.B (Mechanical Engineer)

 

[sanjaygail77]

the normal design factor is 1.5 for any type pipe thickness(as you know that hydro-test has been done to check the strength of the pipe at 1.5 of working pressure). Hence in that way a falling thickness could be calculated

 

[TD2K]

You can back calculate it based on the system's design conditions, the piping material and the applicable code. If this is a service that you only shutdown intermittently, hopefully you have a good inspection program where you know what the corrosion rate is so you can ensure that by the turnaround date the pipe still has sufficient thickness.

 

[ifran31]

Hi,

sanjaygail77 & TD2K tanks for your help,

Questions:
Can I take (12.5 %) of falling in the thickness?
Can I refer to B31.3 code, paragraph 304.1.1?
Is there anyone who can help me to list the steps that the inspection section is changeable?

Regards and have a nice day
R.B (Mechanical Engineer)
(Sorry for my English I am beginner)

 

[austsa]

Wall thickness reduction can be caused by different reasons. Assessment is dependant on amount of reduction and the type of defect. It is too complex to describe here. Suggest you search the internet for "defect assessment". The 3-day course provided (worldwide) by Penspen is highly recommended.