Our previous article discussed the importance of having a specification for weld quality. In this article we’re talking about the importance of one of its basic components: Welding Procedure Specifications (WPSs). Many fabricators don’t have WPSs. They rely in the experience of their welders to select the right parameters. As much as we want every […]
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 […]
It is often incorrectly assumed that quenched and tempered (Q&T) steels are hard to weld or even completely unweldable. This assumption is inaccurate as most Q&T steels have great weldability. However, extreme care must be taken to prevent cracking or loss of certain mechanical properties. A very common quenched and tempered steel is ASTM A514. […]
Porosity is a weld discontinuity that is not as detrimental to structural integrity as cracks, undercut, overlap and lack of fusion. However, it is unsightly and when painted it becomes an eye sore. Because it does not have sharp ends, porosity does not propagate like a crack. The reason for limits to the amount of […]
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 […]
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 […]
Interpass temperature is the temperature of the base metal in and adjacent to the weld joint prior to depositing and additional pass (weld). Maintaining and measuring interpass temperature should be done carefully. Different materials require different levels of preheat and interpass temperature. For this reason it is extremely important that both prehat and interpass temperature be specified […]
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 […]
Corten, or COR-TEN, is the trademark name for weathering steels manufactured by U.S. Steel Corporation. Weathering steels are a family of low carbon steel alloys that were specifically developed to provide higher strength and more importantly eliminate the need to paint to protect against the elements (rain, snow, humidity, sun, salt, etc.). A242 and A588 […]
