Are Concave Fillet Welds Bad?

You may be surprised to know that sometimes they are desired

The following is an exerpt from:  TROUBLESHOOTING FOR NON-WELDING ENGINEERS There is nothing wrong with concave welds so long as they attain the desired throat dimension. AWS D1.1/D1.1M:2020 Structural Welding Code (Steel) states that “there is no restriction on concavity as long as minimum weld size (considering both leg and throat) is achieved.” Concave welds […]

How to Weld Cast Iron

Avoid cracking by following these recommendations

Cast iron is not impossible to weld, although many that attempt to do so end up with cracked welds. The reason welding cast iron is a big challenge is that it contains up to 4% carbon.  This is an insane amount, considering that any material with a carbon content above 0.30%  is already considered “medium […]

Which Welding Process Produces the Strongest Welds

SMAW, GTAW, GMAW, FCAW, MCAW or SAW?

This is a question that is often asked.   The short and quick answer is: they are all the same.  However, to understand why that is let’s take a quick look at the three elements that determine the strength of a weld: Weld length Weld size Weld (filler) metal strength Since we are trying to compare […]

How to get a Qualified Welding Procedure Quickly

Have you ever been in a situation in which you need a qualified welding procedure immediately?  Maybe you just failed an audit and have to halt production until a valid welding procedure is provided.  Or maybe you’re just in a hurry to get started with a new job.  Regardless of the reason you need the […]

What is Stress Relieving and Why We Need It

Stress relieving is a form of post weld heat treatment. In stress relieving we heat a material to a specific temperature; hold it at this temperature for a specified amount of time in order to reduce or eliminate residual stresses; and then cool it at a slow enough rate to prevent these stresses from redeveloping. […]

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 […]

Weldability of Annealed, Normalized, Quenched and Tempered Steels

We frequently receive requests for help developing welding procedures for welding on quenched and/or quenched and tempered steels.  Sometimes the call for help is to determine why these steels cracked after welding and how to prevent it from happening in the future. Understanding the supplied condition of the steel you are going to be welding […]

Welding Hot Rolled vs Cold Rolled Steel

Both hot rolled and cold rolled steels can easily be welded.  However, there are differences between the two that will impact which you choose to use.  Making this choice depends on several factors such as strength, surface finish, dimensional accuracy and cost.   To understand the difference between hot rolled and cold rolled steel and how […]

The Reason Behind AWS D1.1 Minimum Fillet Weld Sizes

It's not what you think

Have you ever noticed that there are design rules that prohibit sizing a fillet weld below a certain size for a given thickness of material? If you look at AWS D1.1/D1.1M:2020 Structural Welding Code (Steel) you can find this on Table 7.7.   If you happen to own a copy of AISC 360-16 Specification for Structural […]