When Using Grit Instead of Shot in a Blaster

I met with a customer the other day who had an older tired blaster so over time they kept adding more and more grit for cleaning power, which lead to 100% grit over shot. The parts they clean, and the finish required do not require a 100% grit to be effective. So, what is the media choice doing to the machine long run, let's explore.

When using steel grit versus steel shot, you can expect some differences in maintenance requirements due to their distinct properties and impact on equipment. Here are some key considerations:

Steel Grit:

1. Abrasiveness: Steel grit is more abrasive than steel shot, which can lead to faster wear on blast equipment components, such as blast wheels, nozzles, and hoses. Expect to inspect and replace these components more frequently.

2. Dust Generation: Steel grit tends to create more dust compared to steel shot, which can impact the efficiency of the dust collection system. Regular cleaning and maintenance of dust collectors and filters are necessary to maintain optimal performance and air quality.

3. Surface Profile: Steel grit produces a rougher surface profile, which may necessitate more frequent inspection and maintenance of the blast room or cabinet lining to prevent excessive wear and damage. It will also lead to having to apply more coatings in the after process then necessary creating coatings waste.

4.Media Recovery System: The angular shape of steel grit can lead to increased wear and tear on conveyor belts, augers, and separators in the media recovery system. Regular maintenance checks and timely replacement of worn parts are essential.

General Maintenance Tips:

• Regular Inspections: Conduct regular inspections of all equipment components, including blast wheels, nozzles, hoses, dust collectors, and media recovery systems, regardless of the abrasive media used.
• Proper Media Selection: Choose the appropriate media for the specific application and surface preparation requirements to optimize performance and minimize wear on equipment.
• Preventive Maintenance: Implement a preventive maintenance schedule to address potential issues before they lead to equipment failure and downtime.
• Training and Monitoring: Ensure operators are trained to recognize signs of wear and damage and monitor equipment performance to identify maintenance needs promptly.

By understanding these differences and maintaining a proactive approach to equipment upkeep, you can optimize the lifespan and performance of your blast equipment when using either steel grit or steel shot.

Try using a mixed media instead:

Using a mixed media approach in blasting can offer several benefits, combining the strengths of different types of media to achieve optimal results. Here are some key advantages:

1. Enhanced Surface Profile

• Customized Surface Finish: Mixing media like steel grit and steel shot allows for achieving a specific surface profile that balances between roughness and smoothness, suitable for various coatings and applications.

2. Improved Cleaning Efficiency

• Comprehensive Cleaning: Different media can target different types of contaminants effectively. For example, grit can break up and remove tough scale and rust, while shot can provide a smoother finish.
• Reduced Passes: Mixed media can often achieve the desired surface condition in fewer passes, saving time and energy.

3. Balanced Wear on Equipment

• Extended Component Life: Combining less abrasive media (like steel shot) with more abrasive media (like steel grit) can help balance the wear on equipment, potentially extending the life of blast wheels, nozzles, and other components.
• Even Distribution of Wear: The varied shapes and hardness levels of mixed media can lead to more even wear patterns on the equipment.

4. Cost Efficiency

• Optimized Media Use: Mixed media can sometimes be more cost-effective as it maximizes the strengths of each type while potentially reducing overall consumption. For example, using a blend might reduce the need for frequent replenishment of the more expensive media.
• Lower Maintenance Costs: Reduced wear and tear on equipment can lead to lower maintenance costs over time.

5. Versatility

• Adaptability to Different Jobs: Mixed media can provide the flexibility to handle a wider range of blasting jobs without changing the media. This is particularly useful in environments where different types of surface preparations are needed frequently.
• Multi-Material Capability: Blasting with mixed media can be effective on various substrates, including steel, aluminum, and other metals, making it a versatile choice for different industries.

6. Improved Surface Coverage

• Uniform Coverage: Mixed media can improve the coverage uniformity on complex geometries and intricate surfaces, ensuring that all areas are adequately blasted.
• Filling and Smoothing: The combination of different media shapes and sizes can help fill pits and smooth out rough areas more effectively.

7. Enhanced Surface Preparation

• Better Adhesion for Coatings: The mixed media can create a surface that promotes better adhesion for paints, coatings, and other surface treatments, improving the overall quality and longevity of the finish.

Implementation Tips:

• Proportional Mixing: Carefully determine the proportions of each media type to optimize performance based on specific project requirements.
• Monitoring and Adjustment: Regularly monitor the blasting process and adjust the media mix as necessary to maintain the desired results and equipment performance.
• Consistent Quality Checks: Implement quality control measures to ensure the mixed media continues to deliver the expected surface finish and cleanliness.

Using a mixed media approach can significantly enhance the efficiency and effectiveness of your blasting operations, leading to better surface preparation, cost savings, and extended equipment life.

Let's face it, blaster eat themselves from the moment it is powered on. Don't let the wrong media choice cost you more wear and tear and overall effect your bottom line. Use the least aggressive media possible to do the job. Question status quo and retest and verify. An old blaster does not perform to the level of a new blaster, so make sure you are reevaluating when adding new equipment to replace the old.

Need help, LS can test your part and let you know what we recommend for best practice when getting to a desired profile and surface requirements. Call the LS team to learn more.

Melissa Gibson - Sales Manager