Should Heat Input Always Be Kept As Low As Possible?

Many ‘experts’ in the welding industry talk about high heat input as something that should always be avoided.  Unfortunately, this is not good advice.  High heat input can be detrimental in many cases, but other times we want to have higher heat input. Heat input is directly related to amperage and voltage and inversely related […]

14 Welding Procedure Specification Variables

A Welding Procedure Specification has several variables which should be carefully specified.  The values selected for the variables discussed below have a significant impact on weld soundness and mechanical properties. It is critical that these values be appropriate for the specific requirements of applicable code and job specifications.  Some of the most important variables in […]

4 Key Factors Affecting the Fatigue Life of Welded Structures

Designing for fatigue is very different than designing for static loads.  One of the biggest challenges is being able to estimate the loads, timing of the loads and duration of the loads.   If you look at a bridge you have to estimate the number of vehicles going on the bridge every day, the weight of […]

Estimating the Fatigue Life of Steel Welded Structures and Components

Using S-N curves and formulas from Clause 2 of AWS D1.1

Heat affected zone crack induced by hydrogen. The crack originates at point of high stress as hydrogen diffuses out of the weld and heat affected zone.

The majority of industrial equipment and welded structural components are subjected to repeated fluctuating loads. These loads are typically of magnitudes that are within the elastic region of the material and well below its yield strength. This means that any deformation of the structure caused by the applied stress will then return to its normal […]

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 […]