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Home > Parts cleaning > Agents > Iron and steel grains
Iron and steel grains
Blast grain from cast iron can be used for roughening up, descaling, derusting and clearing away surfaces. Sharp-edged
blast grain from recompensed high coal steel has long service life and high breaking strength. Steelgrit is used for
cleaning with excellent surface finish, for pretreatment before enamelling, painting and coating. Steelgrit is angular
steel abrasive made by crushing hard steel shot and grading by sieving.
Steel shot is made from high carbon steel which is tempered to give durability and resistance to fracture, used both
for peening and cleaning. Steel shot are derived from casting molten metal in a water tank. The ball-shaped grains
are then graded by sieving. Shot peening is cold treatment of machined parts surface. Peening increases material
fatique resistance and initiates internal strain relief. Steel grain possesses the necessary hardness for the best
cleaning effect and maintains its round shape in the peening machine work mixture. Typical applications include
metal improvement, stress relief, removal of heat treatment residue, mill scale, rust and paint and sand from
castings.
Steel grit tends to clean a little quicker than shot but breaks down at a faster rate. It is essential that media
is kept in a moisture free environment, otherwise it may solidify. Due to the risk of ferrous oxide contamination,
steel shot or grits are not suited to certain applications. Surface corrosion may occur after treatment, therefore
immediate coating or temporary protection is essential.
Chilled iron grit is a white iron structure which shatters on impact rather than wearing round. Being harder than
steel it has a quicker cleaning action but faster breakdown rate. The grits are frequently used to etch structural
steel and components prior to coating with paint, metal spray or plastics. Usage of chilled cast iron poses the same
storage problems of oxidisation as other steel abrasives.
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