Monday, February 22, 2010

[MW:4360] RE: 4357] ASME B31.3 IMPACT TEST

To assess the need of impact testing you should tell us the design conditions... especially the minimum temperature.
 
The assessment should be based on chart 323.2.2A.
 


From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of mauricio padilla
Sent: 21 February 2010 17:58
To: materials-welding@googlegroups.com
Subject: [MW:4357] ASME B31.3 IMPACT TEST


From: mauricio padilla <mauricio_padilla_f@yahoo.com>
Subject: Re: [MW:4351] RE: 4350] DCEN in E7018-1
To: materials-welding@googlegroups.com
Date: Sunday, February 21, 2010, 9:56 AM

Dear Sirs
 
Please I need information about ASME B31.3.
 
 
In piping normally are used the following materials:
1) pipes A106 Gr B /API 5L Gr B
2) fittings ( tee elbow, reducers) A234 WPB
 
My questions are:
 
1) I want to know about is it necessary a Impact testing if the wall thickness of:
 
  pipe API 5L X60 with 10 NPS and wall thickness of

12.7mm(0.5 pulg)?

38.1mm (1.5 pulg)?

2) If I have fittings  A234 WPB of NPS 10" with wall thickness of

         12.7mm(0.5 pulg)?

38.1mm (1.5 pulg)?

Please answer me.
 
Best regards
 
Mauricio

--- On Sat, 2/20/10, pgoswami <pgoswami@quickclic.net> wrote:

From: pgoswami <pgoswami@quickclic.net>
Subject: [MW:4351] RE: 4350] DCEN in E7018-1
To: materials-welding@googlegroups.com
Date: Saturday, February 20, 2010, 5:12 PM

Dear Mr. Asghari,

 

Change of polarity for SMAW is a supplementary essential variable as per ASME Sec-IX(QW-409.4). The definition of this change is illustrated below:-

·        A change from AC to DC, or vice versa; and in DC welding, a change from electrode negative (straight polarity) to electrode positive (reverse polarity), or vice versa.

Generally speaking E-7018/7018-1 electrodes are designed and formulated to operate in DCEP or AC .That's the recommendations put forth in ASME Sec-II,Pt-C, SFA 5.1.Operating them with DCEN may not be advisable unless it it recommended  and certified by the electrode manufacturers.

Change of polarity  alters burning rate of SMAW electrodes, increases tendency for overheating/ stub losses and it could lead to increase of weld defect rates, due to changes in burning characteristics.

Qualifying WPS is only one part of the project activities. If there is no requirement of impact test in the design/ construction code, then the contractor's point may be valid, within the rules of ASME Sec-IX.

However looking at the broader picture , it would be advisable to select polarity as recommended by electrode manufacturer so as to get quality levels required by project specification. I would think you need to discuss this with the contractors and come to some reasonable understanding.

The attached guide would be of help.

I would  think, the viewpoints of the other members of the forum, especially from electrode manufacturers would be more appropriate.

Thanks.

Welding & Metallurgical Engineer/Specialist

Component Integrity Section.

Engineering and Training Services

Ontario Power Generation Inc.

Res:-88,Garth Trails Crescent

Hamilton,Ontario, L9B2X1,Canada

Email-pgoswami@sympatico.ca

Email-pgoswami@quickclic.net

Tel-905-679-9677


From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Ali Asghari
Sent: Saturday, February 20, 2010 6:50 AM
To: materials-welding@googlegroups.com
Subject: [MW:4350] DCEN in E7018-1

Dear All

our contractor  have procured E7018-1,that manufacture recommended DCEP/AC.but they use DCEN in PQR(accepted) and production.

according to this has conflict with AWS A5.01 and manufacture's recommendation. is it true or not?

regards

--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.


--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.

This e-mail and any attachment are confidential and may be privileged or otherwise protected from disclosure. It is solely intended for the person(s) named above. If you are not the intended recipient, any reading, use, disclosure, copying or distribution of all or parts of this e-mail or associated attachments is strictly prohibited. If you are not an intended recipient, please notify the sender immediately by replying to this message or by telephone and delete this e-mail and any attachments permanently from your system.

No comments:

[MW:34820] RE: 34813] Clarification in Rate of heating and cooling.

Hello,   Please see the response below.   Regards.   P. Goswami, P. Eng, IWE.   From: materials-welding@googlegroups.com <materials-weld...