Monday, November 14, 2016

Re: [MW:25698] preheat

The Code is a legal document. It is neither an engineering handbook nor a metallurgy one. The Code is using this value which is a kind of convention since we are talking about a legal documents. This convention (55 degC) is a kind of safety margin to avoid large modifications in heat flow. However, first prevails the sound engineering judgement which has to be used to tune, and not to violate the Code requirements. 


2016-11-14 7:07 GMT+02:00 Kannayeram Gnanapandithan <kgpandithan@gmail.com>:
what is logic to fix 55 degree Celsius, why not 30 or 45 etc 

THANKS & BEST REGARDS,
KG.PANDITHAN, IWE,  AWS-CWI, CSWIP 3.1,
CONSULTANT-WELDING & QUALITY
Mobile no: +919940739349

On Mon, Nov 14, 2016 at 1:08 AM, George Dilintas <dilintas@gmail.com> wrote:
Boxbe This message is eligible for Automatic Cleanup! (dilintas@gmail.com) Add cleanup rule | More info

 If the preheat is reduced substantially, then distortion will increase and cooling rate will increase also substantially. If cooling rate to high, especially during first pass, then lack of fusion is more probable in large thickness. In some bainitic steel  grades rapid cooling rate could lead to martensite formation.  
If interpass temperature will increase substantially then the heat input will increase substantially which could lead to grain growth etc.
The logic behind is that in case of large changes the metallurgy has to be reconsidered

2016-11-13 6:11 GMT+02:00 Kannayeram Gnanapandithan <kgpandithan@gmail.com>:

ASME SECTION IX, QW 406-Preheat

QW 406.1, Preheat temp should not decrease more than 100*F(55*C) and QW 406.3, Inter pass temp should not increase more than 100*F ( 55*C). What is the logic to choose temp limit 100*F( 55*) and consequences if exceed this limitations

THANKS & BEST REGARDS,
KG.PANDITHAN, IWE,  AWS-CWI, CSWIP 3.1,
CONSULTANT-WELDING & QUALITY
Mobile no: +919940739349

--
http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=122787&trk=anet_ug_hm
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.
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To post to this group, send email to materials-welding@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAJzm4eO1gvy1nOczn_%2BajNXT%2Bd%2BOhTEyJ6fZPAbxkw8eVwkyfQ%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.



--
Dr. Georgios Dilintas,
Dipl. Ing. In Aeronautic and Space Engineering
Ph.D in Mechanics of Solids - Computational Mechanics
A.I.S, A.N.I, IRCA Lead Auditor
Welding, Stress Analysis, Corrosion, QA/QC, Failure Analysis, Risk Analysis

--
http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=122787&trk=anet_ug_hm
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.
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To post to this group, send email to materials-welding@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAPOi40ASusf_EAayQMqAS6AEe5Ltm9vQBgtkumFhbR2FyeAejA%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.


--
http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=122787&trk=anet_ug_hm
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.
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To post to this group, send email to materials-welding@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAJzm4eOuDhDQCafo7%3DqF-3FkvRfMj-GFTWKA7z_YYjaMoDPVUg%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.



--
Dr. Georgios Dilintas,
Dipl. Ing. In Aeronautic and Space Engineering
Ph.D in Mechanics of Solids - Computational Mechanics
A.I.S, A.N.I, IRCA Lead Auditor
Welding, Stress Analysis, Corrosion, QA/QC, Failure Analysis, Risk Analysis

--
http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=122787&trk=anet_ug_hm
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.
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To post to this group, send email to materials-welding@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAPOi40A0Y9YxwddU6vwkzN9ygHr-WxVNhDAOBtfV4Nt6Mh2JmA%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.

No comments:

Re: [MW:35289] Welding consumable for S355J2WP material

S355 J2 WP  is a weathering structural steel  It has better atmospheric corrosion resistance. Use E 8018 - W1/W2  Electrodes This is regular...