Compressed air shot peening: why it is preferred over wheel peening

Shot peening is now a well-established technology, particularly used to increase the fatigue strength of manufactured parts and mechanical components.

This process involves “shooting” a controlled jet of metal, glass or ceramic microspheres at very high speed onto the surface of the object to be machined. The high impact caused by the shot introduces a residual compression component, which results in a decisive increase in the fatigue strength of the object.

Why use controlled shot peening?

The advantages of shot peening are many and now widely demonstrated. Precisely because of its high potential, in fact, this technique is now commonly used for multiple machining operations because it allows to: 

  • Increase the fatigue strength of parts;
  • Improve the mechanical properties of components;
  • Reduce the probability of breakage of manufactured parts;
  • Curve or shape surfaces with a high level of precision (particularly useful in the aeronautical or automotive fields);
  • Correct distortions or make surfaces flat and uniform.

Compressed air and wheel peening: which one to choose?

Shot peening can be performed by two techniques or modes:

  • Wheel peening: cheaper and faster processing, but with a lower level of precision.
  • Shot peening by compressed air: more expensive processing, but with a significantly higher level of quality, dictated by the greater precision with which the process is managed.

Although the two techniques originated with different purposes, they have become much closer over time. Nevertheless, they still have substantial differences in terms of results.

Compressed air shot peening, in fact, allows a result with an extremely higher level of precision than wheel peening, which, on the other hand, is more suitable when one prefers to focus on the quantity of the parts to work, rather than their quality.

At this point the question arises: which of the two processes to choose?

As reported earlier, the choice between the two technologies depends on the result to be obtained and the level of precision required.

For the biomedical, aerospace, and automotive sectors, for example, where precision is extremely important, air-assisted shot peening is essential to achieve excellent results and meet the quality requirements.

In any case, the trend in recent years sees compressed air shot peening gaining more and more popularity over wheel peening, not only for quality reasons but also for economic reasons. Because it is a much more accurate process, in fact, compressed-air shot peening allows better fatigue strength achieved on parts and in a significantly more precise manner. This allows for a better economic return, with longer part lifetimes, therefore, higher value and lower cost in the long run.

Why choose compressed air soht peening over wheel peening?

In summary, we can say that compressed air shot peening, compared to wheel peening, allows for:

  • Greater precision of processing;
  • High quality of the workpiece;
  • Increased lifespan of the fatigue-stressed part;
  • More cost-effective in the long run.

Is shot peening a safe surface treatment?

You might think that because of the high pressure with which the grit is shot, shot peening is a technique that risks damaging the machined component. Nothing could be more wrong.

Shot Peening with compressed air allows an unavoidable quality of work, because the entire machining process can be controlled in every step. Precisely for this reason, this technique has already been used for several years in multiple areas where unavoidable quality standards are required

Two striking cases, with profoundly different approaches, are the aeronautical and automotive sectors.

The former, characterized by relatively small production volumes, has focused all its attention on the very high quality of its products to the point of serializing parts and totally controlling every single part produced.
The second, the automotive sector, is characterized by extremely high production volumes that leave room only for statistical controls and, therefore, require extremely high levels of control, standardization and repetitiveness.
This is why the shot peening technique is now considered extremely safe, precise and suitable for the machining of precision components.

It is also important to remember that the attention that the market shows for quality is constantly growing and the specialization of this processing is constantly evolving. Norblast invests every day in research and development to optimize its machines and develop increasingly high-performance, fast and precise techniques and processing methods.

We design high-performance shot peening machines, ideal for machining operations that require high levels of precision. We study the Customer’s needs and requirements to the best of our ability to design tailor-made machines and continuously develop new techniques, for ever greater results.