tube-flange weldment

Date 01-02-2010 11:53

I'm not sure how you would deposit a 0.125 fillet weld with autogenous welding. You don't mention what code is being worked to, but the mention of seal gives me the impression that application would fall under piping codes. I don't work with the B31.X codes in my present duties, but I used to weld under them extensively. My guess would be that there is no provision for autogenous welds in those codes, perhaps somebody that does work with them on a regular basis could comment. As for the callouts - my advice is not to begin the job until you have a print that properly specifies the process. Heliarc is properly the choice for 1/8" fillet welds, but process is the engineer's call, and I would guess you would like to the avoid an argument at the end of the job about what process should/should not have been used. Kick the print back to your customer asking for correct detailing.

By rodofgod (**)

Date 01-02-2010 23:44

Hi All!

It is never a good idea to use Autogenous welding for any method unless it is specificity stipulated in the WPS! In other words, NO!

Regards

By joe pirie (***)

Date 01-03-2010 00:10

out at budweiser on sch 5 stainless they prep the pipe with a portable beveler but set it at 90 deg no bevel
but the pipe as tight as possible. purge it and go . no filler metal allowed.

By j e beckhusen (*)

Date 01-04-2010 18:25

I must have not explained what enough what I was going to weld. The tube fits inside the flange about .375-.50 in. This is not a butt joint ! There is no code that we are to fab. to. It seems to me that adding filler will just extend the length of the tube one-eight in. It,s no different than a lap joint only round. I want to know if it would alright to use the end of the tube(melt off) on to the flange.

By ssbn727 (*****)

Date 01-04-2010 20:49

I hate to read like an echo, but again: What is the grade of stainless steel being used for your application and if you could give us more details on the type of application this is being unly offer sed for... The reason for this is to give you better advice with your situation and nothing more... Remember that without sufficient information we can only guess what to suggest and that's not good enough for anyone!!!

Also, any advice or suggestions are just that and are not to be confused with giving you any type of professional consultation similar to a fee for service type of situation so as a disclaimer, NOBODY in here is liable to any type of suggestions, recommendations, or advice pertaining to any and every welding situation, problem or otherwise that is posted up in this here AWS BBS Grand Central Welding Forum in any, and all of the sections, and posted by any, and all of the participants who either are regular contributors, or occasional viewers, posters, and contributors as well!!! In summary, there are no warranties, guarantees, or any other responsibilities, liabilities, etc. for any and all of the information, knowledge, experience given or offered in here at any time!!! Although there are certain individuals who may think otherwise

Respectfully,
Henry

By aevald

Date 01-05-2010 03:42

Hello j e, I believe that the others are referring to problems that can be encountered when you are possibly welding dissimilar grades of SS autogeneously. With an incorrect match and due to high dilution rates in the GTAW weld pool you could open yourself up to some issues. So, although the "lap joint" weld configuration might not require fillers to accomplish a sound weld with certain SS grades, mixing of certain grades could result in metallurgical issues with either cracks or erosion/strength items being the result. The weld profile of an autogeneous lap can also possibly promote cracking.
Short story..., without knowing the material grade make-up of the SS flanges and tubes it is difficult to say whether you will run into problems down the line. Provide a bit more specifics and you will certainly be given some reasons and justification for support or objection to your line of reasoning. Just a bit to consider. Best regards, Allan

By mightymoe (**)

Date 01-03-2010 03:09

What do your job instructions say? What code are you working with?
Shop I work at requires adding filler metal to each pass, period.
1/8" fillet and no under-cut? Filler metal would make it easier.
Remember you're making a fillet weld not a butt/girth weld.

By 803056

Date 01-03-2010 16:31

No one has asked the question of what alloy is being welded.

While you can join type 316 alloy without filler metal, you wouldn't want to weld type 304 without using a compatable filler metal (think along the lines of 308 F.M.) to ensure there is sufficient ferrite to minimize cracking issues.

Best regards - Al