Introduction to Blast Cleaning

By far, the most common pretreatment for steel constructions prior to painting is blast cleaning, in which the work surface is bombarded repeatedly with small solid particles. If the individual abrasive particle transfers sufficient kinetic energy to the surface of the steel, it can remove mill scale, rust, clean steel, or old paint. The kinetic energy (E) of the abrasive particle before impact is dehned by its mass (M) and velocity (V), as given in the familiar equation  

Upon impact, this kinetic energy can be used to shatter or deform the abrasive particle, crack or deform old paint, or chip away rust. The behavior of the abrasive, as that of the old coating, depends in part on whether it favors plastic or elastic deformation. 

In general, the amount of kinetic energy transferred, and whether it will suffice to remove rust, old paint, and so forth, depends on a combination of  

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