Quality Checks On Welds 2

[rc0213]

We currently have no formal quality checks for welding.

I want to know the least complicated, yet, effective method of inspecting welds, based on your experience.

I was thinking about have a pictures of welds that will pass and fail.

And, empirically, use a radius gage to see if they maintained a 1/4" weld fillet radius.

Any suggestions?

 

[weldstan]

For visual inspection, I had developed photos and actual weldments to show acceptable and unacceptable welds. I also developed training programs of inspectors in use of fillet weld gauges, under cut. excessive reinforcement under reinforcement, high-low measurement, and root gap measuring tools. Acceptable welds are more than the finished product but also includes acceptable weld fit up and includes inspections to assure the correct materials and welding filler metals (properly stored) are used. It also assures that qualified welders are welding to the correct written welding procedure.

 

[0707]

AWS have some instructions for visual inspection of welds, but you also have to caunt on NDT because a weld can´t be avaliated only visualy. Because visualy it can hide lots of defects.

luis

 

[gtaw]

While the photographs will be an aid in showing and identifying weld discontinuities, it is not an end-all method of providing all the instruction the welders or inspectors need to understand how to evaluate the welds. There need to be a means of measuring the size of the weld and the size, depth, or length of the unacceptable defects. How deep can the undercut be before it is unacceptable? How long can the undercut be before it is deemed unacceptable? If a fillet weld is undersized, is there any latitude to how small it can be before being judged to be too small. Is any porosity acceptable? What type of porosity needs to be evaluated? Is overlap acceptable for your application? The list goes on and on. Your employer should take a hard look are what weld conditions will be detrimental the your product and establish limits for what is acceptable or unacceptable.

The American Welding Society, Miami, Florida, publishes B1.11, A Guide to the Visual Examination of Welds that can serve as a basis for identifying different weld discontinuities, but it doesn't establish acceptance limits.

Best regards - Al

 

[Dhurjati Sen]

A good welder is foremost for a good weld joint.

Then come the joint design (the role of fitters / fabricators).

After that its the consumables and accessories (filler wires, electrodes, shielding gas, baking / heating ovens).

If you don't have the above three, pictures and fillet weld gauges would only make matters worse.



DHURJATI SEN
Kolkata, India

 

As the old adage goes:

"If you want it quick and cheap, it won't have quality.
If you want it cheap and with quality, it won't be quick.
If you want it quick and with quality, it won't be cheap."

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[gtaw]

DHURJATI SEN, you are correct with regards to quality involves more than looking at a completed weld and pronouncing it "good" or "bad".

In visual inspection we have a mantra; Before, During, and After.
There are things to check before welding begins, things to check while the weld is being deposited, and things to check once the weld is complete.





Best regards - Al

 

[kingnero]

ISO 5817 / ISO 10042 show using sketches, examples of bad welds.
You can buy posters on the Lincoln website, that show actual photographs of weld defects.

 

[gtaw]

There's few things worst than someone that hasn't had the training and experience attempt to perform a thorough visual examination on a weld. I mentioned the mantra; Before, During, and After for visual examination already. the mantra needs to be taken to heart. The individual tasked with performing the visual inspection must have a basic understanding of the technology, processes, how to read drawings and understand the symbology used to specify the welds, a little basic understanding of metallurgy so they understand how the metal responds to the thermal cycles associated with welding and the significance and importance of the material specifications, the typical discontinuities found in both the base metal and the weld, and of course they need to be able to use a standard to determine the acceptable limits for the various discontinuities. After all, you don't want the individual to reject welds that are acceptable, but you don't want them to accept welds that don't meet the standard.

In many case, a good welder can be trained to perform the visual weld inspection. His experience and practical knowledge of welding is useful because he knows where the discontinuities are most likely occur and what most likely caused the problems. His knowledge and skill as a welder can be utilized to address the shortcomings so the overall quality can be improved.

Depending on where one lives, there are several recognized programs for training and certifying welding inspectors. You might consider sending a couple of people to the training courses even if they don't actually get certified. Many are available online using the Zoom platform. ASME, AWS, and several other organizations offer courses closely aligned with the training needed to perform visual weld inspection for very reasonable costs.

Best regards - Al

 

[Dhurjati Sen]

A star to your last post gtaw Sir, reading it was a real pleasure.

DHURJATI SEN
Kolkata, India

 

[gtaw]

Thank you DHURJATI SEN.

I taught visual welding inspection for many years. There is more to it than meets the eye if you expect a thorough job.

Best regards - Al

 

There is more to it than meets the eye

I saw what you did there.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."