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[MW:5085] RE: 5067] RE: Fittings P235GH & P265GH material for -10 deg C ?

my opinion is other way
para 4.1 (a) of directive states, they should be sufficiently ductile and tough, and where appropriate must comply with 7.5
but how do you prove that without testing? yes in case of ASME we have exemption curves to prove the material is sufficiently ductile up to certain temperature/thickness.
refer Table Z A.1 of EN13480-2 (harmonized product std),  para 4.1.6 and Annex B will support ESR 7.5
para 4.1.6 states steel shall have min impact energy >=27J @ test test temp as per Annex B, but not higher than 20 °C
 
more opinions welcome.


From: Pisat, R. (Rahul) [mailto:Rahul.Pisat@akzonobel.com]
Sent: Thursday, May 06, 2010 3:27 PM
To: Bathula Raghuram (Mumbai - PIPING)
Subject: RE: 5067] RE: Fittings P235GH & P265GH material for -10 deg C ?

yes , we do need CE marking,
ESR 7.5 does requires a proof or Ductility of material. but its a sub clause of 4.4(a)..which says when appropriate,the characteristics of material must comply with the requirements of 7.5,
 
But if the design code does not require a impact test of a material at particular design temp. or thickness , then there is no need to do a impact test,
( this is as case of ASME B31.3, where we do not need impact test of Carbon steel with thickness less than 12.5 mm for -29 degC)
 
 
The European supplier of pipes and piping  says that they do not do impact testing of material.
 
Also as per material standards EN 10216 , EN 10253, Impact test is a optional requirement.
 
 

Kind regards

Rahul Pisat
Piping Specialist
Plant Design

Akzo Nobel Technology & Engineering B.V.
Postal address: PO Box 9300, 6800 SB  Arnhem, the Netherlands
Visiting address: Velperweg 76, 6824 BM Arnhem, the Netherlands

T +31 26 366 4706, F +31 26 366 3401,
Visit our website @ www.akzonobel.com/te  

 


From: Bathula Raghuram (Mumbai - PIPING) [mailto:R.Bathula@ticb.com]
Sent: donderdag 6 mei 2010 11:24
To: Pisat, R. (Rahul)
Subject: RE: 5067] RE: FIttings P235GH & P265GH material for -10 deg C ?

i suppose you also have CE marking requirement,  ESR 7.5 states imapct testing is mandatory at MDMT
even in  EN 13480 how do you use thtable Tkv is material test temperature (without testing how one can  derive this).


From: Pisat, R. (Rahul) [mailto:Rahul.Pisat@akzonobel.com]
Sent: Thursday, May 06, 2010 1:19 PM
To: Bathula Raghuram (Mumbai - PIPING)
Subject: RE: 5067] RE: FIttings P235GH & P265GH material for -10 deg C ?

Do we have to do Impact testing for the material ?
 I am bit confused about actual requirement of Impact testing of material and code Documented values to prove the impact test energy values.
 
yes the design code is EN13480.,  and if you refer annex. B,  fig. B2.3.2-2 ( as welded condition for Rp <= 310 N/mm2)
, for Design reference temperature at -10deg.C, and for a Fitting thickness at 10mm & less , there is no Impact test requirement.
How do we interpret this table ?
 
Am I correct that for thickness 10 mm at temperature at -10 deg C..there in no need of Impact test requirement ?
 
Kind regards

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Bathula Raghuram (Mumbai - PIPING)
Sent: woensdag 5 mei 2010 6:07
To: materials-welding@googlegroups.com
Subject: [MW:5067] RE: FIttings P235GH & P265GH material for -10 deg C ?

What's is your design code and MDMT?
If you are using EN13480 (refer para para 4.1.6 of part 2), which meets ESR 7.5 of PED 97/23/EC, In my opinion you can use this material with impact testing as per Annexure B at MDMT (-10 °C)

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Pisat, R. (Rahul)
Sent: Tuesday, May 04, 2010 7:53 PM
To: materials-welding@googlegroups.com
Subject: [MW:5065] FIttings P235GH & P265GH material for -10 deg C ?

Hello all,


The carbon steel Pipe ( EN 10216 & EN10216 - grade P325GH & P265GH ) & flanges ( EN10222- P245GH) are defined till  -10 deg C.

but for Fittings, grade P235GH and P265GH material, are defined are defined only upto Minimum temp. of 0 deg C as per EN10253 table 9.

Is it allowed to use these fittings materials for service at -10 deg C ? if yes then what additional we must take into consideration.

or do we have to go for low temperature material of P355N or P335NH material grade ?

waiting for your replies

Kind regards

Rahul




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