Weld Spec Help !!!!!

I have some experience with welding but not a lot of experience with welding specs and need some help.

I have a product that I am working on that requires some welding of 4130 steel tube and brackets and 6061 Aluminum formings. I would not consider the welds to be structural. I need to specify a weld spec of some sort to have control of the weld process. My company has used an Aerospace weld spec in the past for some flight test equipment (sorry I don't remember the spec number) but to weld to this spec requires welds to be welded by a certified welder and inspected by a certified weld inspector. Welding to this spec is expensive and my team has come to the conclusion that welding to this Aerospace spec for this project is not necessary.

My question is are there any basic weld specs that can be called out that are good for general welding applications that most shops conform to?

Example Tig Weld Per XXXXX using Filler Material XXXX

Are there any resources out there that I can use to find a spec that meets my needs or do I just need to start buying and reading the different specs?


Any help is appreciated.

Thank you

There are two different things you may be talking about here. The first is what standard you weld to. In your aerospace example, it may have been AWS D17.1. The "normal" spec for structural steel is either AWS D1.1 (for =<1/8" thick) or AWS D1.3 (for <=3/16" thick). The "normal" spec for aluminum is AWS D1.2. If you need something to put on a drawing that you're sending to a weld shop (as in your example) you would probably use one of these three.

Unfortunately, I don't know of any standards for non-structural welding. Such items usually just get 'welded.' D1.1, D1.2, and D1.3 don't require certified welders and weld inspectors, but they do require 'qualified' welders and inspectors. Many weld shops do the qualifications in house. For each process, the welder does a coupon and then they bend it.

As far as specifications, there are Weld Procedure Specifications (WPS). These are sheets giving the details of a certain joint/process. For example, a WPS might be for single pass FCAW-G fillet welds in mild steel. This WPS will have voltage, wire speed, gas type/flow, preheat requirements, etc. Under the various AWS standards, the weld shop should have these on file for the types of welding they do. For the common types of welding, they have a bunch of pre-qualified WPS's already done, so the shop can use those. For more exotic things, there are some tests you need to do to make sure that the welding process will actually work.

Here's an example WPS I just googled: http://weldoffice.com/documentation/howto/pWPS%20sample%20printout.pdf

How about asking the end user-customer---what they expect? That's what dictates what's done.

.....or......Since you've already determined that the parts are not structural (or critical!)....then don't call out any spec's.
and just wing it.

If the items are "non structural", why 4130 ?

Might as well be mild steel.

A bad weld in 4130 is still a bad weld, and the resultant cracking
(from bad technique) will be worse than a simple weld in Mild Steel.

digger doug said:

If the items are "non structural", why 4130 ?

Might as well be mild steel.

A bad weld in 4130 is still a bad weld, and the resultant cracking
(from bad technique) will be worse than a simple weld in Mild Steel.

Click to expand...

I didn't design the parts just working on polishing off the drawings. I guess you could call them semi structural, if they fail it would be bad but if they are welded half decent there is no way they will fail.

I need to buy and read the AWS D1.1 - D1.3 specs so I know what they specify.

Consider HAZ failures in both 6061 and 4130 weldments in the design and processing of the assemblies.
It's HAZ failures that make or break things, especially in both alloys listed.

patrickpnw said:

I didn't design the parts just working on polishing off the drawings. I guess you could call them semi structural, if they fail it would be bad but if they are welded half decent there is no way they will fail.

I need to buy and read the AWS D1.1 - D1.3 specs so I know what they specify.

Click to expand...

Sounds like they are structural, just very overdesigned.

You can get the scope pages of each spec for free on the AWS website. I doubt both D1.1 and D1.3 are necessary. Pick which you need based on the thickness of the steel.

patrickpnw said:

I didn't design the parts just working on polishing off the drawings. I guess you could call them semi structural, if they fail it would be bad but if they are welded half decent there is no way they will fail.

I need to buy and read the AWS D1.1 - D1.3 specs so I know what they specify.

Click to expand...

I was a detailer once.

The devil is in those details, and you need to ask the designer.

And you need to ensure that you do your diligence until you
get it right.

digger doug said:

I was a detailer once.

The devil is in those details, and you need to ask the designer.

And you need to ensure that you do your diligence until you
get it right.

Click to expand...

Maybe you can answer a question for me. In structural steel land, where is the demarcation line between the engineer and the detailer? I've always done all my own design, analysis, and drawings, so I'm not sure how they do it in companies that specialize in structural steel work. Does the engineer, for example, tell you what type of connection he wants and then you draw it up per the AISC code, or do they do a full design and you're just responsible for getting it pretty and legible on paper?

Why not ask the welder what he wants to see on the drawing? I wouldn't spec a weld on a drawing without consulting the person doing the welding first.

I dont see why you wouldnt just require certified welders. Any welder good enough to hire for work like this is gonna be certified, or just plain lazy. I hire 1 or 2 certified welders a year straight from welding school, and kids today can weld the pants off any old timer I have met (and I am an old timer myself) and pretty much every decent welding student gets his or her certs before graduating.
If it needs to be done right, certified welders and certified inspectors are the paper trail that save you from big lawsuits.
Its a small price to pay.

Other thing i have seen over here more than a few times is some wacky low spec that no one has a shop certified to do. Hence it ends up costing more than simply using a common all be it "better" Standard thats already in place and in common local use. Really pays to look at what the vendors are setup to do and try and make the design fit in if you want to really lower costs. Hence the aircraft grade welding may be cheaper, but then simply omit the post weld testing requirements or similar.

If its truly non critical, then simply calling out the process and filler to be used on the weld symbol mealy stating of sound quality - desired high visual quality etc should cover things.