EN 13480 and impact test

[ElCidCampeador]

Hello,

according to a project of a client, I have to build a pipeline which is designed acc. to EN 13480.
Pressure design is 1,5 bar, Temperature design 230°C, MDMT= -20°C.

Material of pipes, fittings and flanges: P245GH.

Checking on the internet and each item standard (e.g. EN 10253 for fitting), it seems not correct to use that material because its common use is 0°C or higher temperature.

So:

1) Do you think P245GH is correct @ assigned MDMT?
2) Does EN 13480 require impact test @ MDMT for that material or you can't use it at all?

I'm a little confused, I usually work with ASME, not EN...

Thank you

 

[1503-44]

Also not fluent with EN, but from ASME experience I would choose a different material, as there apparently far better materials available for use at -20C, such as ASTM A333. Even use of API 5L at that temp is acceptable, if you do the low temp Charpy tests.

 

[ulyssess]

Material tested at 0°C can be used at a lower temperature, see EN 13480 Part 2 Appendix B, Method 2 , subclause B.2.3.

 

[ElCidCampeador]

Material tested at 0°C can be used at a lower temperature, see EN 13480 Part 2 Appendix B, Method 2 , subclause B.2.3.

Thanks for the tip...but how Figure B.2.3.2-2 works is a human mistery like gioconda's smile...bah

 

[1503-44]

You might recommend to your client, via an engineering decision notice, to do the low temp Charpy anyway. They can decide and you've got it in writing.

 

[ElCidCampeador]

Can anyone help me with Figure B.2.3.2-2 of EN 13480? How does it work?

 

[ulyssess]

Unfortunately I only have edition 2012 at my hand and not the latest edition 2017. In edition 2012 there is no figure B.2.3.2-2 and this was at my knowledge not changed in edition 2017. I can explain the procedure using fig B.2-2. This nomogram is valid for minimum yield strength <= 265 MPa, as-welded condition. The test temperature TKV for P245GH is 0 deg. C.
If your reference thickness eB is 10 mm than you can use the material down to a design reference temperature TR of -60°C.
If your reference thickness eB is 35 mm than you can use the material down to a design reference temperature TR of -20°C.
Thicknesses in between are to be linearly interpolated.
If your material is PWHT or non-welded than use fig. B.2-1.
Reference thickness eB is taken from table B.4-1