Steps to determine if welding preheat can be eliminated?

Testing the effects of preheat in small parts and assuming it will be the same on large sections is a mistake.

As discussed in our previous article, and many times in the last 50 or so, preheat is necessary in steel welding to control the cooling rate.  More specifically, preheat is used to slow the cooling rate down in order to prevent excessive hardness in the heat affected zone (HAZ) which  can lead to cracking.   Before […]

Factors Affecting Cooling Rates of Welds and Heat Affected Zones

Different ways to manage the rate of cooling

Our next article will discuss a question we are asked quite often: Can we eliminate preheating before welding?   Preheating is necessary to slow the cooling rate down after welding which in turn avoids excessive hardening of the weld and heat affected zone.  Eliminating preheat can lead to hydrogen induced cracking and catastrophic failure.  A […]

Why More Customers are Requiring Qualified Welding procedures

If you own or work at a job shop you may have noticed an increase in the number of customers that require the use of qualified welding procedures to build their products. Some fabricators are even getting this request from long time customers who never required them in the past. So why is this? The […]

How to Determine Acceptable Weld Quality

Certain industries that involve welding of their products have very strict quality standards to ensure the production of sound welds.  Many others however, do not.  They simply weld and unless one of their products fails they don’t pay special attention to welding procedures, detailed inspection of welds or testing the skill (performance) of their welders. […]

How to Become a Certified Welding Inspector

A career as a Certified Welding Inspector (CWI) can be very rewarding.  This certification, which is awarded by the American Welding Society, carries a lot of weight both nationally and internationally.  The main responsibilities of a CWI is to make sure that welding operations are manufacturing products that comply with specified welding codes and standards. CWIs essentially are expected […]

The AWS D1.1 1G Welder Qualification Test

The AWS D1.1 Structural Welding Code (Steel) welder qualification plate tests consists of a groove weld with a 45-degree included angle. The plates are prepared to a knife’s edge and a ¼ in [6 mm] backing strip is used.  The test for unlimited thickness will use plates that are 1 in [25 mm] thick.  Anything […]

Danger of Using the Wrong Shielding Gas for GMAW

In our previous article we mentioned that a customer was inquiring about running their 98% argon / 2% carbon dioxide (98/2) shielding gas on mild steel.  This gas is used on stainless as it maintains the amount of reactive gas (in this case CO2) under 3%.   Our quick answer was “yes, you can weld carbon […]

Etching Solutions for Steel, Stainless, Aluminum and Other Metals

For high-quality macro-etches

The qualification of welders and welding procedures often involves macro-examination of welds.  Performing macro-etches is a relatively simple procedure, but strict guidelines must be followed to ensure safety.  Most chemicals used in etching solutions are hazardous and must be handled accordingly.  Any person etching with these chemicals must  familiarize him or herself with the corresponding […]

Importance of Implementing a Specification for Weld Quality

Understanding the basic components

If you have been reading our articles for some time you know how strongly we feel about having documented welding procedure specifications which have been qualified by testing or prequalified in conformance with code requirements. Yet when we recommend that these very important documents be developed and used in production we get a lot of […]

Weld Toughness vs Weld Strength

If you have ever been tasked with selecting the right specification and grade of steel for a particular application you know there are hundreds of choices.  Typically these are based on the materials tensile strength and yield strength.  There are many factors that go into selecting the right base metal for a given application.  In […]