Re: [MW:28360] RE: 28355] Water Vapor in welded joints

Dear sir,

My work shop is in Kerala, India. The interesting thing is that the vapours are seen even in afternoon (Humidity may be >65%). After the weld got cooled, the surface of the joint is like somebody poured water on the joint. This is visible in SS only.This water vapours are not making any issue in Weld joint.

I will share the photos latter.

Is it related to heat conductivity of SS?

Is it related to flux as commented by a member of this group ? if so which component/metal contained in flux?

Thank you all for the replay.

Regards,

Hareesh K V

On Fri, Sep 28, 2018, 7:59 PM PGoswami <pgoswami@quickclic.net> wrote:

Hi,
This is a case of moisture condensation. It's possible if the relative humidity(RH) factor is high, typically above 60% or more. In Indian subcontinent after the Monsoon RH could be very high contributing to this. Where's the location of your plant? Do you have any humidity control in the shop floor?, it may help.
Stainless steel does not require any preheating however some preheating ( typically up to 30-40 DegC) is advisable to get rid of the moisture accumulation, typically happening due to condensation.

Thanks.

P.Goswami.P.Eng, IWE.
Welding & Metallurgical Specialist
Email:pgoswami@quickclic.net,pradip.goswami@gmail.com

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Hareesh K V
Sent: September 28, 2018 12:24 AM
To: materials-welding <materials-welding@googlegroups.com>
Subject: [MW:28355] Water Vapour in welded joints

Dear Veterans,

After the cooling of weld joints, water vapor is seen in the surface of weld joints. What is the reason? This is particularly seen in SS welded joints.

Regards,

Hareesh K V
+91-8547859202
--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
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.
Visit this group at https://groups.google.com/group/materials-welding.
For more options, visit https://groups.google.com/d/optout.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
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.
Visit this group at https://groups.google.com/group/materials-welding.
For more options, visit https://groups.google.com/d/optout.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
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.
Visit this group at https://groups.google.com/group/materials-welding.
For more options, visit https://groups.google.com/d/optout.

Heat tint (temper) colours on stainless steel surfaces heated in air // Heat tint

Introduction The colour formed when stainless steel is heated, either in a furnace application or in the heat affected zone of welds, is dependent on several factors that are related to the oxidation resistance of the steel. The heat tint or temper colour formed is caused by the progressive thickening of the surface oxide layer and so, as temperature is increased, the colours change. Oxidation resistance of stainless steels However, there are several factors that affect the degree of colour change and so there is no a single table of colour and temperature that represents all cases. The colours formed can only be used as an indication of the temperature to which the steel has been heated. Factors affecting the heat tint colours formed Steel composition The chromium content is the most important single factor affecting oxidation resistance. The higher the chromium, the more heat resistant the steel and so the development of the heat tint colou...

Materails FAQs

Q: What are equivalents for standard Q 235 B (and Q 235 A) for U-channels? (asked by: boris.vielhaber@vait.com) A: DIN Nr. = 2393 T.2, 2394 T.2, EN 10025 W. Nr. DIN 17007 = 1.0038 Design DIN 17006 = RSt 37-2, S235JRG2 (Fe 360 B) Q: What is St DIN 2391 BK material? (asked by: dmcandrews@automaticstamp.com) A: Precision steel tubes, cold-finished/hard. Q: What is C.D.W. Boiler Tube? (asked by: montydude123@yahoo.com) A: Cold Drawn Welded Boiler Tube. Q: WHAT IS W.Nr. 1.4301? PLS TELL US IN EASY LANGUAGUE (asked...

The Schaeffler and Delong diagrams for predicting ferrite levels in austenitic stainless steel welds

Introduction Ferrite is important in avoiding hot cracking in during cooling from welding of austenitic stainless steels. 'Constitution diagrams' are used to predict ferrite levels from the composition by comparing the effects of austenite and ferrite stabilising elements. The Schaeffler and Delong diagrams are the original methods of predicting the phase balances in austenitic stainless steel welds. Nickel and chromium equivalents A 'nickel equivalent' is calculated for the austenite stabilising elements and a 'chromium equivalent' ferrite stabilising elements. These are used as the axes for the diagrams, which show the compositional equivalent areas where the phases austenite, ferrite, martensite (and mixtures of these) should be present. Although intended to show the phase balance of weld fillers, these diagrams can also be used to illustrate the phase balance of the 'parent' material. There are different diagrams for dif...

Materials & Welding

Search This Blog