In the world of industrial coating, shot blasting machines are essential tools which are capable of giving metal parts the finish and strength needed to withstand the rigours of everyday use. However, behind their apparent simplicity and usefulness lies a whole world of shot types and processes that define their effectiveness and applications.
One of the fundamental aspects to consider is the diversity of shot available on the market. From metal shot such as steel, aluminium or zinc, to non-metallic shot such as glass or plastic, each type has particular characteristics that determine its suitability for different purposes. While some are more abrasive and are used for cleaning and surface preparation, others are softer and are used for more delicate finishing processes.
But what is the purpose of each type of shot?
The answer lies in the physical and chemical properties of each material. Metal shot, for example, is effective in removing rust, corrosion and encrusted dirt from metal parts, preparing them for protective coatings or to improve their aesthetic appearance. On the other hand, non-metallic abrasives are preferred for applications requiring gentler treatment, such as cleaning delicate surfaces or removing paint without damaging the surface.
However, beyond the obvious benefits of using shot blasting, it is crucial to also understand the effects it has on a surface when applied. The abrasive action of the blast media on the surface of a part can cause changes in roughness and texture, as well as generate residual stresses that can influence its strength and durability. Careful selection of the type of shot blast media and the operating parameters of the shot blasting machine are therefore crucial to ensuring optimal results and avoiding unnecessary damage to the parts.
