Skip to main content

[MW:3496] RE: 3491] Porosity

By Materials & Welding
You may be between a rock and hard place.  Replacing the filler metal may be the only reliable option.
 
I have experienced porosity problems with GTAW filler metal during procedure qualification.  After changing welding torches, welding machines, and shielding gas batches, analyzing shielding gas, changing base metal coupons etc., it was found that the filler metal (wire) had residual amounts of drawing compound/lubricant.  We found this almost impossible to remove and, even if one could remove it, it would have been excessively costly both monetarily and time wise.  I ended up having to scrap the existing stock and repurchase a different brand.  Problem went away with replacement filler.  Note that this was from a respected, world wide, filler metal company - but they did not draw the wire.  It was just rebranded.  Caveat emptor.
 
I suggest that you try and obtain a small amount of filler metal from another manufacturer/supplier.  If the problem goes away, then I would condemn the current filler metal and replace it.
 
John
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of ozgur kalyoncuoglu
Sent: Monday, October 12, 2009 3:06 AM
To: materials-welding@googlegroups.com
Subject: [MW:3491] Porosity

Dear Friends;
 
We are constructing a pipeline with Semi - Automatic Orbital GTAW Welding System which is consist of cladded pipes. Pipe Material is API 5L X65 + Inconel 625 Overlay. We have completed nearly 20 km and when we were in a shortage of wire, we ordered a new batch of wire (Inconel 625). After receiving this wire we had porosity in all the joints especially below 3 oclock position.
 
Our habitats are in perfect condition, there is no any small wind inside.
Our gas (Argon) seems clear (up to this time we didnt face any problem).
We are cleaning the bevels with acetone.
 
Under the light of above explanations can you suggest me someways, how to avoid this porosity other than changing the wire.
 
Best regards
 
Ozgur
 

--~--~---------~--~----~------------~-------~--~----~
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.
-~----------~----~----~----~------~----~------~--~---

Comments

Post a Comment

Popular posts from this blog

Materails FAQs

By Materials & Welding
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...
21 comments
Read more

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

By Materials & Welding
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...
Post a Comment
Read more

Re: [MW:10788] ON PLOT PIPING & OFF PLOT PIPING

By Materials & Welding
Piping systems involved for the flow lines and gathering lines from the well head isolation valve to the production facility or processing plant isolation valve are determined as OFF PLOT. ON PLOT defines piping system in the processing plant and production platform. ANSI/ASME B31.4 applies for off plot piping system. B31.4 allows the use of either API 1104 or ASME section IX (as appropriate). However, occasionally, a very small system such as piping within 500 feet of a processing plant (some client also said 400 feet) may be declared B31.3 rather than B31.4. When B31.3 is invoked, only ASME Section IX is used. before you decide which code to use for welding procedure and/or welder qualification for pipe welding, you have to know the design and construction code applicable to the system. Please read far enough into scope and diagram illustrating the application of either B31.3 and B31.4 hope this helps rgds 2011/4/21 pradip kumar sil < pradipsil@gmail.com > Dear all, ...
Post a Comment
Read more