What are the different types of abrasive blasting?
- Vacuum blasting
- Soda blasting
- Steel grit blasting
- Dry-ice blasting
- Pencil blasting
In metal manufacturing, the different types of abrasive blasting are essential in achieving the desired type of surface finish for a material. Typical metals and alloys that undergo abrasive blasting include steel, stainless steel, copper, iron, or aluminum. Aside from creating a type of surface finish, abrasive blasting is also done to eliminate corrosion on the material, prepare it for further coating, remove unwanted substances, and improve its durability.
Although abrasive blasting is oftentimes referred to as “sandblasting” this is just but one type of technique that uses sand material as the medium for blasting. Various other methods exist, like vacuum blasting, steel grit blasting, dry-ice blasting, vacuum blasting, pencil blasting, and many more. All of them vary in the type of medium and the method of application. Continue reading to learn more.
Sandblasting typically involves the silicone dioxide medium or sand silica. In this method, the silica particles are sprayed at high speed and high pressure onto the given specimen. With the use of the machine, the operator will fire the nozzle onto the alloy/metal, making sure that it has been adequately prepared.
This is one of the most common methods of abrasive blasting. It’s fast, efficient, and easy to set up. Depending on the size of the material, the operation can be completed in as fast as a few minutes to an hour, without any compromise on the quality.
For example, if a steel pipe is sandblasted, its surface will become much smoother and cleaner. It also removes the formation of rust or any kind of oxidation that can affect its structural properties.
Unlike the sandblasting technique, vacuum blasting does not involve the direct use of any abrasive material. Instead, the “blasting” is done with the use of vacuum-based equipment that siphons all the unwanted materials, grime, dirt, and other unnecessary materials from the surface of the metal.
The one advantage that vacuum blasting has over the other technique, is that it’s a dust-free method, meaning that there is less cleaning to be done after the operation has already been completed. However, it may not be as practical as sandblasting, since vacuum blasting is much slower and may take time to set up.
As the name suggests, soda blasting involves the use of a soda-based substance — usually a sodium bicarbonate solution or baking soda. Compared to sandblasting, the soda solution doesn’t contain large-sized particles that can cause potential dents under the surface of the metal/alloy specimen. Instead, the solution is considered soft and less harmful to the specimen’s physical structure.
As established before, abrasive blasting techniques are done in the repair of a metal that has corroded portions. But for soda blasting, it’s also ideal for preventing rust formation and creating a shiny, metallic finish. This is effective on ferrous materials or iron-containing materials such as copper, steel, stainless steel, cast iron, or carbon steel.
Steel Grit Blasting
There is another abrasive blasting technique that may also use granules or particles from alloys. A perfect example of this is steel grit blasting which uses minuscule steel grits that are projected onto a specimen’s surface at high-velocity.
Steel grits are a good choice due to their high-cutting abilities — this makes them excellent at removing much harder particles that are deeply embedded onto the specimen’s surface. Like sandblasting, steel grit blasting can be done in a short time, which is ideal in high-volume production of billets, blooms, slabs, or slugs.
Due to the type of medium used in steel grit blasting, however, the very same particles may also lodge into the different crevices on the specimen — especially for materials that have seams or threads. This may affect the quality of the product once it’s already been applied and fitted with other components.
Dry-ice is the main medium found in this blasting method and has similar properties to soda blasting. Particularly, both mediums don’t cause any harmful reactions to the targeted specimen. But one distinct feature with dry-ice blasting is the thermal shock reaction that occurs between the pellets and the metal.
In this case, thermal shock happens due to the low temperature of dry ice pellets that are blasted at high power onto the specimen’s surface. Due to the extreme difference between the two temperatures, the pellets effectively break the bonds that may have formed between the unwanted contaminants and the specimen.
While dry-ice blasting may be efficient, it should be performed in environments that are well-ventilated. This is because too much of the substance can invariably increase the carbon dioxide levels in the location, which may cause potential respiratory issues.
Pencil blasting and steel grit blasting also have similar qualities, in that they both use abrasive materials in the form of alloys. For pencil blasting, these particles are called pulverized aluminum oxide that’s commonly mixed with high-pressure air.
This method is effective at removing corrosion, as well as, cleaning the material in its entirety. It’s suitable for any material that needs high-precision in order to remove any burrs or smoothen rough surfaces.
In this guide, you’ve learned about the different types of abrasive blasting that can be classified according to pencil blasting, sandblasting, grit blasting, vacuum blasting, soda blasting, or dry-ice blasting. Each method has its own advantages and advantages and it depends on the manufacturer to choose the more ideal one.
Regan Steel does total sandblasting on their steel products. If you’re looking for high-quality materials, you may contact us for inquiries! You may also check out our other products and services here.