Written by Rosler CEO Bernhard Kerschbaum, this article was originally published in The Fabricator.

Modern metal fabrication operations aren’t like the fab shops of old. Many are clean, well lit, with employees working in fresh, filtered air. Yes, some operations in fabrication are, well, just plain dirty—and manual blasting is a prime example. The work isn’t pleasant, requires protective gear, and if the booths aren’t maintained or set up properly, they can constrain workflow in a serious way.

Options in blasting automation abound, but before diving into all that technological wizardry, try laying some groundwork by answering a fundamental question: What must the blasting operation accomplish?

Shot Blasting Versus Shot Peening

Shot blasting (or just “blasting” if using a different media other than shot) prepares a metal surface while shot peening aims to change the metal’s properties (see Figure 1). Certain aerospace applications require precise levels of stress relief (or other changes to material properties), and they use specialized shot-peening technologies to achieve it. Precision shot peening of landing gears is a prime example, with the process optimizing surface stresses, eliminating microcracks and the stress risers around them.

Most metal fabricators employ blast cleaning for the vast majority of their applications, cleaning and preparing a metal surface for the next manufacturing step, usually painting. If a beam or plate isn’t blasted correctly, paint won’t adhere properly. However, some fabrication operations do employ a kind of peening—not as precise as high-end peening applications, but it’s peening nonetheless, with the media impacting the surface and causing compressive stresses that aim to change the material’s properties.