The first step in specifying a blasting operation is the correct selection of materials to be employed.
The following are the main characteristics of the most common ones available in the Brazilian market.
Their physical characteristics (spherical shape, high density, hardness and resistance) and chemical (inert material, not reacting with the vast majority of substances) give them a prominent place among the other products used for blasting. They are used for cleaning, finishing satin. of great beauty, precision deburring, engraving or decoration and are irreplaceable for low intensity shot peening. They are practically non-abrasive, which opens up a huge field of application that was previously closed to the process. Cleaning a carburettor, deburring hypodermic needles (40 microns diameter balls usually pass five side by side in the hole of a fine needle), cleaning general molds, shot peening on cutting tools or blades. aviation turbines and many other important applications have become viable with glass spheres.
They are supplied in various specifications. They are used to eliminate larger burrs, for some cleaning and finishing cases and also indispensable for high intensity shot peening. Operating costs are small due to their long service life (300 to 400 cycles) and low abrasion.
It is the most commonly used material for general cleaning and surface preparation for bonding (anchoring) of coatings. They are more abrasive than spheres more equally economical.
It is a highly abrasive product of great hardness. It is extremely efficient for cleaning and anchoring even for high liability coating such as plating or plasma application.
Walnut or peach or Brazil nut shells, corncobs, fish bones and others, ground and graded, are employed for cleaning high precision parts because they are even less abrasive and softer in effect than glass beads. They are widely used for deburring brittle plastics as they do not impair surface gloss.
| Materials | Abrasive Action | Surface Contamination | Powder Generation | Finishing uniformity | Cleaning Efficiency | Operational cost |
| Glass spheres | Virtually Nil | Null | Low | Great | High | Low |
| Spherical Steel Shot | Average | Low | Low | Great | High | Low |
| Angular Steel Shot | High | Low | Low | Good | High | Low |
| Aluminum oxide | Very tall | Low | High | Good | High | Medium |
| Organic Materials | Null | Low | Low | – | Low | Medium |
Intensities: 1- Plastics / 2- Glass / 3- Low and Medium / 4- Medium and High
Note: Sand is a material that poses serious health risks to operators to the extent that it is prohibited in many countries.
Phone
+55 (11) 3388-3534
Rua Muniz de Souza, 306
Aclimação, São Paulo - SP
E-mail:
zirtec@zirtec.com.br
