Rosler Metal Finishing builds shot blasting machines that are equipped to prepare the surface of sand castings as well as collect removed contaminants for a consistent workpiece finish and the health of the utilized machine and personnel.
What design features must be considered in blast turbines used for the cleaning of sand castings?
Baked-on molding sand, sand cores, and scale/rust on the sand castings are difficult to remove and require turbines with a lot of fire power. Turbines with curved throwing blades, such as Rosler’s Gamma G series, have proven to be exceptionally effective since, compared to straight-bladed turbines, the curvature of the blades generates up to 25 percent higher throwing speeds!
This helps reduce cycle times and energy consumption and contributes to overall higher cleaning efficiency. To minimize costly downtimes, the wear protection along with impeller, control cage, and throwing blades must be made from wear-resistant materials like heat-treated cast steel or forged tool steel ensuring extremely long uptimes.
How can dust explosions and premature wear be prevented and high temperatures be handled in dust collectors for foundry applications?
Special attention must also be paid to the handling of dust in conjunction with shot blast machines for sand castings. The filter fabric must not only be able to cope with extremely abrasive sand and scale/rust residue in the exhaust air but must also withstand high temperatures of up to 500° F.
That is why many foundry applications use special heat- and abrasion-resistant bag filters instead of the standard pleated cartridge filters.
In the case of non-ferrous casting materials, like aluminum, extra measures must be taken to protect the dust collector against the risk of dust explosions. Wet dust collectors are a suitable solution.
The Rosler Way
At Rosler, we understand that working within the foundry industry is an important, dangerous, and often dirty job. That’s why we design our shot blasting machines with your work piece needs, employee safety, and environmental control measures in mind. Whatever sand castings your process includes, Rosler Metal Finishing can learn about your challenges to develop and deliver a solution. Contact us today to discuss your unique challenges.
Be sure to catch up on our previous posts in the series including: