Causes of Porosity in Submerged Arc Welds

Submerged arc welding is typically done automatically, meaning it is not done by hand, but rather set up as hard automation.  The operator simply controls the welding machine and torch position to obtain the desired results.  Typically,the system is run by an operator, not a welder.  So when problems come up, the operator may not […]

Effects of Voltage on Weld Quality

Voltage is one of the most important variables in a welding procedure.  It is also one that is sometimes misunderstood.  You may ask five welders what effect voltage has on a weld and you may get five different answers.  This is because voltage can do a lot of things, some good and some bad. Understanding […]

FCAW prequalified welding procedures and their limitations

Dangers even if you follow all the requirements of AWS D1.1

The use of prequalified welding procedures has many advantages as well as many disadvantages.  One danger of using prequalified welding procedures is that AWS D1.1 allows for quite a bit of freedom in weld sizes.  If you look at Table 5.1 –Prequalified WPS Requirements of AWS D1.1/D1.1M:2020 Structural Welding Code (Steel) you’ll see that in […]

Which is the best shielding gas for MIG welding?

Today we received two different requests for help pertaining to shielding gas selection.  The first caller requested a chart that tells them what materials can be welded with the different shielding gases that they had.  They wanted a chart that can be provided to the welders to make sure they used the right gas on […]

Short-arc vs Globular Transfer in GMAW

What is the difference between globular and short-circuit transfer? Short-circuit is a mode of metal transfer in GMAW in which metal is transferred from the electrode to the weld pool via a series of electrical shorts. When the electrode (wire) touches the base material a short occurs and the arc goes out.  At this point […]

7 Variables That Affect Weld Penetration

Complete joint penetration (CJP) welds will have the exact same effective weld size regardless of welding process.

Getting deeper penetration, or at least adequate penetration is very important in welding.  There are a few applications in which we wish to minimize penetration, but in general we always want good penetration.  There are many variables that affect penetration, some more than others.  It is important to know how each individual variable affects the […]

5 Factors that Contribute to Silicon Island Formation in Welds

The formation of silicon islands on welds made with the GMAW (mig) and MCAW (metalcore) processes is very common.  For the most part, these silicon islands are not a problem.  However, if the weld is to be painted, you better remove these islands. Otherwise, they will eventually pop off and leave an unpainted spot in […]

How to Qualify a WPS for Welding Stainless to Mild Steel using AWS D1.6

Macroetch locations for welding procedure qualification of fillet welds.

It is very common to weld stainless steel to mild steel.  But, when it comes to qualifying a welding procedure it can be somewhat confusing.  Do you follow AWS D1.1 (Steel) or do you following AWS D1.6 (Stainless Steel)?   Or is there another code or standard you should use? The answer to this question is […]

Is Weld Strength Affected by Shielding Gas Mix?

Can our selection of shielding gas affect the strength of a weld and other important mechanical properties?  Absolutely!  The difference is more pronounced when using flux-cored (FCAW) wires than when using mig (GMAW) wires, especially as the wire’s tensile strength goes up.   Although we can affect strength by using different gases, what we should be […]

Rainbow Colors in Stainless Steel Welding

Are they good or bad?

Different joints will have different levels of admixture (the mixing of weld metal with base metal) . The higher the admixture the more silicon islands will form on the surface of the weld.

We receive several calls about welding stainless and the beautiful rainbow colors, or lack thereof, on the weld and heat affected zone.  Is the tinting an indication of quality?  Are these colors acceptable? Do they show that the weld had enough heat to penetrate?  Why do they need to be cleaned?  The questions are endless. […]