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[MW:2119] Re: preheat SA- 516 gr 70

By Materials & Welding
Purpose of Pre heating are as follows:
 
1) To prevent Hydrogen Induced cracking- This risk is very high with CS material if thickness is more than 25 mm thick.
2) TO remove moisture and minor dust and dirt
3) It reduces fast cooling otheriwse it results in to unwanted unhealthy mircrostructure.
4) It some time help for distortion control.
 
Regards

On Thu, May 7, 2009 at 11:20 AM, nilesh <nilesh_parsekar@yahoo.com> wrote:
Dear Saul,
 
             We are also tank fabricator but we never do preheating.It is not the requirement as per API 650 if you have proper WPS with supporting PQR.We have welded 35mm A 516 GR 70 in our last project without preheating without anyproblem.
 
regds 

  Nilesh Parsekar,
 Sr QC Co-ordinator
 (Dip Mech,API 510,API 570,AWS-CWI,NDT LEVEL2)
 Belleli Energy Spa
 FUJAIRAH - UAE


--- On Wed, 5/6/09, SAUL VASQUEZ T. <svasquez@ingetanques.com> wrote:
From: SAUL VASQUEZ T. <svasquez@ingetanques.com>
Subject: [MW:2114] preheat SA- 516 gr 70
To: materials-welding@googlegroups.com
Date: Wednesday, May 6, 2009, 7:50 PM

 

Dear   all

 

We are   API 650 steel tanks with  steel ASTM  516 gr70 and our client requests that preheat to 70°C - 100°C is this correct? The API 650   code section 7-1 that says that  preheat at 10°C



thanks all

 

 

 

Cordial saludo

Kind regards

Saul Vasquez T.

--------------------------------

INGETANQUES LTDA

Cra 8B Nº 190-81 

Tel. 57 (1) 6794382  Fax 57 (1) 6723793

CEL. 320-3469363  y  316-5388051

Bogota D.C.    Colombia.  http://www.ingetanques.com/

 

P Antes de imprimir este mensaje, asegúrese que es necesario. El medio
ambiente está en nuestras manos. No malgastes los recursos. Ten en cuenta
que son limitados.

 



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