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Re: [MW:13341] What is Marangoni Effec and its relation with

By Materials & Welding
Hi,
Its a nice question.
Marangoni effect is a matter of sulphur content in the chemical composition of material to consider/make full penetration welds in TIG welding. If suphur content is very less it may leads to incomplete penetration. If a sulphur content in optimum level will give good penetration for TIG welding.
 
Thanks & Regards,

(Karthik)

Karthikeyan.S
QA/QC Manager
Getabec Energy Co.,Ltd.
379,Moo6,Soi8,Nikhomphatana,
Rayong-21180,
Thailand.
Phone: 0066 38 897035-8 (Off)
Fax: 0066 38 897034
Hand Phone: 0066 892512282

From: anilkumar <anilb2000@gmail.com>
To: Materials & Welding <materials-welding@googlegroups.com>
Sent: Tuesday, December 27, 2011 6:25 PM
Subject: [MW:13327] What is Marangoni Effec and its relation with

Respected All,
I found the ollowing lines in an welding article on orbital
welding, that for a  cryogenic fluid carrier, inner pipes
were chosen of 4306 stainless steel, diameters between 84
to 273 mm.L = 11,5 m / 6 m).Thickness (mm) 2.9 .Inner pipes
were supposed to be  in contact with cryogenic fluid. With
different cryogenic temperatures: 1.8 to 80 K .xxxx
Conlcuding remark was "Practioner should pay attention about
Chemical composition to avoid "Marangoni effect" during welding.

Plz. educate me, what is Marangoni Effec and its relation with
weld material composition.?

Regards.
ANIL BARIK



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