What is a shot blasting machine?

A shot blasting machine is an industrial surface treatment equipment that uses high-speed metallic abrasives to clean, strengthen, or roughen the surface of workpieces. By projecting steel shot, steel grit, stainless steel shot, or other abrasives onto the surface at high velocity, it effectively removes rust, mill scale, welding residues, sand, and other contaminants while improving surface quality.

Shot blasting machines are widely used in industries such as metal fabrication, foundry, steel structures, engineering machinery, shipbuilding, and automotive manufacturing. They are one of the most common and mature solutions in the field of industrial surface preparation.

Working Principle of a Shot Blasting Machine

The core component of a shot blasting machine is the blast wheel. Driven by an electric motor, the blast wheel rotates at high speed, accelerating metallic abrasives through centrifugal force and projecting them uniformly onto the workpiece surface.

When the abrasives impact the surface, they generate strong impact and cutting action, achieving the following results:

• Removal of rust, mill scale, and surface contaminants
• Cleaning of casting sand and residues on castings
• Improvement of surface roughness for better coating adhesion
• Surface strengthening to enhance fatigue resistance

After blasting, the abrasives and dust are collected by the recovery system. Qualified abrasives are recycled for reuse, while dust is separated and removed through the dust collection system.

Main Functions of a Shot Blasting Machine

Surface Cleaning
Efficient removal of rust, oxide layers, welding slag, and old coatings from metal surfaces.

Surface Strengthening (Shot Peening)
Introduction of compressive stress on the surface to improve fatigue strength and extend service life.

Surface Roughening
Creation of a uniform surface profile to enhance adhesion for painting, coating, or plating.

Improved Surface Appearance
Produces a clean, uniform, and consistent surface finish.

Common Types of Shot Blasting Machines

Depending on the shape of the workpiece and production requirements, common types include:

Hook Type Shot Blasting Machine – Suitable for medium and large workpieces

Tumble Belt Shot Blasting Machine – Ideal for small castings and forgings

Turntable Shot Blasting Machine – Suitable for single or regularly shaped parts

Through-Type Shot Blasting Line – Designed for continuous processing of steel plates and profiles

Overhead Conveyor Shot Blasting Machine – Suitable for automated production lines

Common Abrasives Used in Shot Blasting

Cast steel shot

Steel grit

Bearing steel shot and grit

Stainless steel shot and grit

Different abrasives provide varying cleaning intensity, surface roughness, and service life, and should be selected based on material type and process requirements.

Application Industries

Foundry and forging industry

Steel structure and bridge construction

Construction and engineering machinery

Automotive and auto parts manufacturing

Shipbuilding and offshore engineering

Pipelines, pressure vessels, and storage tanks

Summary

A shot blasting machine is an efficient, stable, and highly repeatable industrial surface treatment solution. By selecting the appropriate machine type and abrasive, it can meet a wide range of requirements—from heavy-duty rust removal to fine surface preparation—while significantly improving surface quality and subsequent processing performance.