Shot Peening
Shot Peening relies on a motor-driven impeller to propel steel shot (ranging from 0.2 to 3.0 mm in diameter) at high velocity onto a workpiece's surface. This process induces compressive stress, transforming welding tensile stress into beneficial compressive stress, thereby enhancing the component's fatigue life. Commonly used in industries like automotive, aerospace, and heavy machinery, shot peening is effective for parts such as gears, aircraft components, and bridges. It is often mistakenly believed that only shot peening can achieve strengthening effects, but both shot peening and shot blasting can be used for this purpose, each with its own advantages. For instance, shot peening offers high processing volume and speed, though the blasting angle is fixed and only the initial speed can be adjusted via frequency conversion.
Sand Blasting
On the other hand, uses compressed air to propel steel shot or grit (ranging from 40 to 120 mesh, approximately 0.1 to 2.0 mm in diameter) onto the workpiece. This method is versatile and can remove rust, old coatings, and even oil, making it ideal for surface preparation before painting. It is widely used in shipbuilding, steel structure fabrication, and other applications requiring high-quality surface preparation, such as when using high-strength bolts for connections.
Key Differences:
Method of Propulsion:
Shot peening uses a mechanical impeller, while sand blasting relies on compressed air.
Particle Size:
Shot peening typically uses larger particles, whereas sand blasting employs finer grits.
Application:
Shot peening is preferred for strengthening and stress relief, while sand blasting excels in cleaning and surface preparation.
Both methods have their unique advantages and are essential in various industrial applications, contributing to the durability and quality of the final products.
