Weld classification

By Lawrence (*****)

Date 11-17-2008 19:10

Randy, Welcome to the Forum!

First off it would be wise to determine the visual inspection criteria of the code you are compliant with.

You may find that vigorous adherence to the code will solve your problem with no further action.

However, some welds require a specific cosmetic appearence, for example, mountain bike frames often will look for a specific number of ripples per inch as a gague for appearence... That would need to be worked into your contract doccumentation above and beyond the code requirement and presented to your fabricator up front.

By swnorris (****)

Date 11-17-2008 20:06

You can also ask your fabricator to submit a sample weld on a mock up piece to you for your review and approval.

By DaveBoyer (*****)

Date 11-18-2008 03:32

Randy, just a comment on the item pictured: That will give people a greater respect for the power required to generate electricity. In the '60s when the power company was trying to get the area residents to accept the idea of a nuke plant in Our backyards, they had a tandem bike hooked to a generator. Bottom line is that 1 man did manage to keep a 100watt lightbulb lit, but 2 men could hardly power a TV set [big old power hog of the era].

By 803056

Date 11-18-2008 04:47

I would recommend the use of workmanship samples.

Commercial welding standards may not give you what you are looking for because most are concerned with the structural integrity of the weld rather than the appearance. Were I forced into a corner and if I had to specify a welding standard for your application, I would opt for D17.1 (an AWS welding standard for aerospace applications), Class A welds. They would most likely meet your expectations for cosmetically pleasing welds and still meet integrity requirement. However, the project specification should clearly state that while the visual criteria of a Class A weld must be met, additional NDT is not required if the welds are not intended to carry applied loads. Class C welds can be specified for those welds that do not need to meet stringent cosmetic requirements.

Still, workmanship samples are something that the fabricator, welder, and inspector can see and touch. Nothing is better than a physical specimen that can be used for comparison and evaluation.

Best regards - Al

By Sberry

Date 11-18-2008 16:43

I would think it would be fairly obvious to any decent fabricator, they really shouldn't "need" to be told what an acceptable job looks like?

By 803056

Date 11-18-2008 16:47

If only that were the case.

Al

By kipman

Date 11-18-2008 16:55

I agree with Al on this. If you're worried about cosmetic appearance, a workmanship sample (or samples) is worth a thousand words.
Mankenberg

By Bob Garner (***)

Date 11-18-2008 16:58

This might be a little unrelated but somewhat parallel. Once had a welding project where the welds had to have an acceptable appearance as on your project. It would have been nice (and should have been in the contract) to give specifics describing acceptable weld appearance, but this didn't happen. Instead, I was left to argue with the contractor doing the work. We went around and around, finally we both looked down at a railing to post connection that looked good. And this became the job appearance standard. Luckily, the railing was just outside the fabricator's office so it was there for ready reference by all the welders as they came to work. In the end, it worked.

Bob G.

By 803056