hydrotest pressure calculation as per PED

[mechyp]

I am trying to calculate hydro test for PED work.

Material are used for construction SA 350 Lf 2 CL 1,SA 420 WPL6, SA 516 GR 70
Design Tmp: 365 C
Design Pre: 7.5 bar (MAWP)

Per Annex 1 7.4 hydro test pressure is no less than

-1.43 x MAP (this is i understood)
but

-1.25 x MAP x LSR (Lowest stress ratio)- (stress form ASME Section-II part D- this is right ?)

So the consideration of MAT means multiply the ratio for stress between test and design temp right ?

PED allowable stresses (if so there are many possible ratio's dependent on the method that results in the lower stress value...per Annex 1 7.1

please correct if wrong.

yogesh

 

[XL83NL]

Yikes, my previous post is gone. What I basically wrote is that, although PED may be vague at times on how to execute certain aspects of the ESR's in Annex I, more guidance can be found in the PED Guidelines.
Second, keeping in mind harmonized standards (like EN 13445 for PV's) comply with PED requirements; have a look at a harmonized EN design code for the scope of your pressure equipment, and look for analogies.
So take EN 13445 and look how hydrotests are determined in there, if your designing a pressure vessel.

Otherwise, wait for SJones to bump in, he can tell you more than me I think.

 

[DSB123]

yp3135,
posting on more than one forum is not the done thing!!!!

 

[XL83NL]

Hah, now I know why it looked my post wasgone.
+1 on DSB123, keep it together on 1 place.

 

[mechyp]

by mistake I posted in piping grope.

that's why re post in boiler pressure grope.


yogesh

 

[SJones]

Don't rely on me - I'm just the simple corrosion guy with a copy of the documents! In Annex I, 7.4 it says 'maximum loading', I'm not sure that that is the same as LSR. Allowable stresses are defined in Annex I, 7.1.

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[OSIRIS7]

In the latest edition of EN 13445-5 §10.2.3.3.1 is a nice reference on "how to establish".

Kelly

 

[mechyp]

kelly

as per EN 13445-5

Pt= 1.25 x pd x fa/fd

pd= design pressure is the maximum allowable pressure.

I think it same as in ASME (fa/fd) is LSR

my question is any other loading that we have to consider in this formula (Pt= 1.25 x pd x fa/fd)


thanks for reply

yogesh