Are You Using The Right Abrasive for Your Application?
The abrasive used in the blast cleaning process has a major influence on the efficiency of cleaning and on the profitability of the blast cleaning system. Yet, many companies have never reviewed their abrasive requirements to make sure that they are using the most optimum abrasive to match what they would like to accomplish with the parts they are currently blast cleaning.
As previously mentioned, having the right work mix, consisting of grains of various sizes of abrasive, is critical to the most efficient and consistent blast cleaning operation. Always checking to make sure that the hopper is full also is important to maintaining a proper work mix.In addition, make sure the Air-Wash System and airflow in the machine is adjusted properly to ensure clean, contaminant free abrasive during the blast cycle. Failure to check any of these simple areas will cause longer blast cycles, less clean parts, and higher maintenance costs.
However, the proper selection of abrasive is also critical, not only from the standpoint of blastingresults but also from a maintenance standpoint. An abrasive of good quality will help tokeep operating costs at a minimum.
Abrasives are generally classified in shape as either "shot" or "grit" and are designated as such be the letters "S" for shot and "G" for grit preceding the size number.
Grit is angular in shape presenting numerous sharp cutting edges especially adaptable for matte or etched finishes. It is best to use grit if an anchor pattern is desired on the finished parts so that paint, powder coating, or any coating can adhere to the surface of the metal
Shot is spherical in shape which produces peening to provide a smooth, more attractive finish. Many different sizes and types of shot and grit are available in today's market to meet various requirements and applications. If you have any problems in abrasive selection, one of our representatives will be glad to help you make the selection best suited for your needs.
Smaller sized Shot, such as S-70, S-110, or S-170, is best to use when looking for a fine, smooth shot finish. It is best used in blasting relatively small castings or the removal of light scale from forging or heat treated parts or machined parts. It is also good for the removal of mill scale, rust, and other deposits. Grit, such as G-80, G-50, or G-40, is also good for these applications but will leave a medium etched finish on the parts.
Medium sized Shot, such as S-230, S-280, or S-330, provides a medium light finish and good coverage in the blast cycle. The medium sized Grit, such as G-25, will provide a sharp etch to the parts. These sizes of Shot and Grit are best used in the blasting of grey iron, mall iron, light steel castings, medium forgings heat treated parts and heavy mill scale as well sa heavy rust deposits.
There are larger size Shot and Grit, but the sizes above are the most commonly used in most applications. We recommend the carbon steel shot and grit offered by Metaltec Steel for all of the various sizes of shot or grit. More information can be found on our website.
If concerned about ferrous contamination on your parts or if you are blasting non-ferrous parts you may need to consider using stainless steel shot or grit. Go to our website to review the options offered by Vulkan Blast Shot Technology for stainless steel abrasives.
If you would like additional information or would want an evaluation from one of our blast cleaning experts please