How do I Pass a Weld Test? (Part 2)

Note to readers: This article is a continuation of Welding Digest’s previously published article (https://weldingdigest.aws.org/blog/how-to-pass-a-weld-test). Matt Scott answered some more questions in relation to passing a weld test.

Welding Out the Rest of the Plate

While welding out the interpasses during a test, pay attention to the leading edge of the weld pool and the lower areas of the weld pool around the 4 and 8 o’clock marks. The focus is to ensure the leading edge is carving into the weld/base metal and the lower areas of the weld pool are being filled so no undercut is left.Portland Community College (PCC) student Alex Oh displays his detailed fitup preparation.

While welding out the groove, it is important to watch the shoulder of the groove. This is a primary reference point and will assist you in filling the groove up evenly from start to finish. As the plate is welded out, its temperature will increase as you progress from one end to another (I refer to this as the chimney effect). This increase in heat will increase your deposition. Adjust your travel speed to accommodate for an even fill. Watching the reveal of the shoulder is critical to obtaining an even fill, which will help in producing a smooth cover pass.

String vs. weave bead is another factor that will be addressed in the welding procedure specification (WPS). I use a stringer bead technique with a slight oscillation while welding structural steel. Although I oscillate the electrode slightly, the total bead width remains in the realm of a stringer width. This movement allows me to smooth out the bead and provides a window to see if undercut develops in the lower portion of the weld pool, and if so, I will still have time to fill it.

Adjusting your amperage is another critical aspect of a test. This sounds simple enough, but many individuals breeze over this point. Therefore, having material to practice the new amperage requirements is a critical step.

PCC student Mateo Rodriguez stops for a last inspection point before taking his test.

Weld placement decisions are also critical to a test. During the weld out, valleys are created adjacent to the deposit of the previous weld. Sometimes a decision needs to be made whether to deposit one wider weld or two smaller beads to fill that valley. This decision point is where you will need to trust your gut. The critical factor is based on whether your electrode can touch the bottom of the valley or not. Too narrow of a valley puts you in a situation where you do not have enough arc relief. In other words, the valley is so tight that when you deposit the weld, the weld pool will freeze before the slag separates out. Hence, you will trap slag. Deep valleys need to be ground open to provide enough relief for the new weld. Proceed with caution, however, because grinding may not be allowed based on the information in the WPS.

The sidewall is another aspect to concentrate on while welding out a groove weld. When depositing a weld into the sidewall area, adjust the work angle (side angle) to point into the wall a little more. This helps to ensure fusion at this intersection.

For the cover pass, I recommend these three adjustments:

1. 1. Fill the groove until it’s almost full (1/16 to a 3/32 in. of reveal/shoulder left). This sets you up for a successful cover pass.

2. 2. Monitor the plate temperature. Let the plate cool longer before running the cover passes.

3. 3. Run the same amperage as the previous passes. Some welders like to reduce their amperage, which is another viable option. However, this approach runs the risk of snuffing out the electrode when running a tight arc.

PCC student Alex Collins showcases his successful bend tests.

How long will your certification be good for?

The answer to this question can be found in AWS D1.1, Structural Welding Code — Steel.

“6.2.3 Period of Effectiveness

6.2.3.1 Welders and Welding Operators. The welder’s or welding operator’s qualification as specified in this code shall be considered as remaining in effect indefinitely unless:

(1) the welder is not engaged in a given process of welding for which the welder or welding operator is qualified for a period exceeding six months, or

(2) there is some specific reason to question a welder’s or welding operator’s ability (see 6.25.1).

6.2.3.2 Tack Welders. A tack welder who passes the test described in Part C or those tests required for welder qualification shall be considered eligible to perform tack welding indefinitely in the positions and with the process for which the tack welder is qualified unless there is some specific reason to question the tack welder’s ability (see 6.25.2).”

Please refer to part 6 in this standard for many more qualification details.

In Closing

The more tests you take, the better you will get. I still remember the first AWS D1.1 weld test I took in school. It was an epic rookie failure. I did not take the time to prepare my plates correctly. I left a “land” (A nonstandard term for root face) on one plate when it needed to be a knife edge. Hence, incomplete fusion at the root showed on the x-ray. That failure fueled my practice, and I not only perfected my preparation skills, I also increased welding skills and passed the next test. Although this first test experience started with a failure, it gave me the knowledge and skills to go on and pass the AWS D1.5, Bridge Welding Code, test years later. Stay the course, perfect your craft, and test whenever you can.

Here’s wishing you the best of skill for your next test.

This article was written by Matt Scott (welding instructor and department chair at Portland Community College, Portland, Ore.) for the American Welding Society.