Sandblasting Steel Shot

When steel shot is used in open sandblasting, it faces conditions that differ from closed wheel blast machines. The abrasive is carried by a high-pressure air stream, travels through hoses and nozzles, and strikes the surface in a more scattered pattern. Particles that work well inside a wheel machine may fracture too easily or create uneven coverage in open air. This Sandblasting Steel Shot was developed specifically for that open-blast environment. It is supplied by Shandong Haishan Industrial Technology, a manufacturer with an annual capacity of 100,000 tons and customers in more than 50 countries.

Manufacturing and Screening Steps

The production process starts with high carbon steel, melted and atomized into spherical shot. After heat treatment, the shot passes through multiple screening stages. A final secondary screening removes hollow particles, irregular shapes, and broken pieces. The target hardness is controlled between HRC 42 and 48, which is slightly tighter than the common SS steel shot range of HRC 40–50. This narrower band helps maintain consistent impact behavior and fracture resistance under high-pressure air blasting.

Each batch is tested for chemical composition, hardness, and particle size distribution. Hardness is measured on mounted cross-sections with a Rockwell tester. Sieve analysis follows SAE J444.

Key Technical Data

Chemical composition is checked by direct-reading spectrometer. The values below are typical for this product grade.

Open-environment sandblasting performance

• Fracture resistance under air pressure: The tighter hardness control and removal of defective particles help the shot withstand repeated high-speed impacts against steel surfaces without breaking as quickly as general-purpose shot. This contributes to lower dust generation on site.
• Uniform particle size: Consistent sizing reduces the chance of fine particles clogging the nozzle or coarse particles causing uneven surface profile. The result is a more predictable finish across the blasted area.
• Flow through hoses and guns: Spherical shape and controlled size distribution allow the shot to move smoothly through sandblasting equipment, reducing the risk of blockages during long outdoor jobs.
• Reusable after screening: After collection, the shot can be screened and reused if the particles are still within the required size and shape range. This is different from silica sand or mineral abrasives that break down quickly.

Where This Product Is Used

This shot is intended for open sandblasting operations, particularly outdoor projects where portable equipment is used. Common applications include:

• Removal of rust and old coating from storage tank exteriors
• In-situ bridge maintenance and repainting preparation
• Outdoor refurbishment of construction machinery
• Container exterior cleaning before recoating
• Surface preparation of large steel sculptures and structures
• Pre-blasting of ship hull sections

It is not recommended for closed wheel blast machines such as hook-type or through-type systems, because the particle flow characteristics and impact pattern are optimized for air blasting rather than centrifugal wheel throwing.

Quality Control and Documentation

Every production batch is sampled for chemical composition, hardness, and particle size distribution. The laboratory is equipped with a direct-reading spectrometer, Rockwell hardness tester, and sieve shaker. Certificates of analysis and test reports are supplied with each shipment. Additional documents, including ISO 9001:2015 certification and metallographic reports, are available on request. Batch traceability is maintained from raw material to final shipment.

 

Packaging and Storage

Standard packaging is 25 kg bags with a moisture-resistant PE inner liner inside a woven polypropylene outer bag. 1,000 kg bulk bags on pallets are available for large orders. For export, pallets are prepared to meet ISPM 15 requirements. Store in a dry, covered area, and keep bags off the ground to prevent moisture absorption.

Common Field Questions

What hardness should I expect from sandblasting steel shot?

The product is controlled to HRC 42–48. This range is slightly tighter than the standard SS steel shot range of HRC 40–50, which helps maintain consistent performance under high-pressure air blasting.

Can this shot be used in closed wheel blast machines?

It is not recommended for closed wheel blast machines. The particle flow and impact behavior are tuned for open air blasting. For closed machines, a standard steel shot or grit may be more suitable.

How does this shot compare to silica sand for outdoor blasting?

Silica sand breaks down quickly and generates harmful siliceous dust. Steel shot lasts much longer and can be recycled after screening. It also produces a more consistent surface profile. The initial cost is higher, but the consumption per square meter is usually much lower.

Can the shot be recycled on site?

Yes, after collection, the shot can be screened to remove broken particles and contaminants. Reusable particles can be returned to the blasting pot as long as they are still within the required size and shape range.

What particle size should I choose for open sandblasting?

The best size depends on the surface condition and the required profile. For general rust removal on steel, S230–S390 are common. For lighter cleaning or thin sections, a finer size such as S170 may be appropriate. We can recommend a size after reviewing the project details.

Does this shot produce less dust than ordinary steel shot?

Because the shot is screened to remove hollow and weak particles, and the hardness is controlled to resist fracturing, it typically produces less dust than general-purpose steel shot under the same blasting conditions. Actual dust levels also depend on the workpiece condition and dust collection system.

Particle Size Distribution