5 MORE Questions You Should Know for the CWI Exam

And fundamental principles for the fabrication of steel structures

Today we’ll cover 5 more very important concepts that are governed by the AWS D1.1 Structural Welding Code (Steel). If you missed our last post with the first five questions simply click here.  These concepts can show up as questions in the Certified Welding Inspector (CWI) Exam. As stated in our article from last week, […]

5 Questions and Answers You Must Know for the CWI Exam

And fundamental principles for the fabrication of steel structures

If you have taken or hope to take the CWI exam you probably have searched for some practice exam questions.  In practicing for the code book portion of the test you may have come across a few questions for which you could find the answer, but didn’t really understand the importance of the question or […]

How to Weld Titanium

Titanium is a metal which is silvery gray in color and has about half the density of steel (0.163 lb/in3).  Pure titanium is relatively soft has very low ultimate tensile strength.   For use in structural applications titanium is alloyed with chromium and iron, chromium and aluminum, manganese and aluminum and manganese alone.  These alloying elements […]

Effects of Shielding Gases in GMAW

Using the right shielding gas is essential not only to prevent porosity but to get proper penetration, the mechanical properties you desire including weld strength, and overall weld quality.  In order to select the right shielding gas you need to consider the following: –          Alloy of filler metal –          Material thickness –          Mode of GMAW […]

Bigger (Weld) Is Not Always Better

When it comes to fillet welds, bigger is not always better.  A fillet weld is easy to measure, simply take out your fillet weld gauges measure it.  However, there is an incorrect assumption that a bigger weld (as measured with a fillet gauge) is always stronger than a smaller weld. Before we get into this […]

What Filler Metal Should be Used to Weld Carbon Steel to Stainless Steel

And can you use stainless wire to weld carbon steel to carbon steel

It is not uncommon to find fabricating shops that are welding a variety of metals including carbon steel, stainless steel, aluminum and nickel alloys.  In many cases some of these materials need to be welded to other types.  Once very common situation, especially in automotive applications is welding carbon steel to stainless. One of the […]

The Advantage of Using Undermatching Filler Metals on High Strength Steels

High strength steels are becoming more and more popular in steel construction.  Higher strength means we can reduce the thickness of the base material and thus reduce weight.  This is very important not just in vehicles but in static structures as well.   However, higher strength steels usually bring about a few issues that if not […]

Preheat and Interpass Temperature for Structural Steels

Preheating of structural steels is carried out primarily to slow the cooling rate after welding and prevent the formation of martensite.  Martensite makes the weld and the heat affected zone (HAZ) very hard and brittle.  This newly formed microstructure is susceptible to cracking.  By slowing the cooling rate we reduce or eliminate the formation of […]

The 9 Clauses of AWS D1.1 Structural Welding Code Explained

The most widely used welding code in North America, and perhaps the world, is AWS D1.1/D1.1M Structural Welding Code – Steel.  It is specified as the quality standard in hundreds of contract documents every year.   Yet, we find that less than half of the fabricators that need to use it have a sound understanding of […]

6 Mistakes That Can Lead to Cracked Welds

Cracks on welds are never good.  Welding codes always have allowances for porosity, undercut, weld sizes, and even weld profiles.  However, there is never an allowance for cracks.  Being a linear discontinuity, a crack will tend to propagate through the weld and into the base metal with relative ease, especially in cyclically loaded structures.  So […]