The Difference Between Shot Blast Cleaning and Shot Peening

With similar names and styles of operation, the terms ‘shot blasting’ and ‘shot peening’ are often conflated. In reality, shot blasting and shot peening provide two entirely different functions. This article is going to explain exactly what shot blasting and shot peening are, and the differences between the two.

Abrasive blasting

Before delving into each individual process, we must first discuss what abrasive blasting is. 

Abrasive blasting is the process of shooting a stream of abrasive material against a surface at high pressure. This process can be used with a variety of different abrasive materials, against a variety of different surfaces for a variety of different reasons. Thus, both shot blast cleaning and shot peening are types of abrasive blasting, but the difference stems from their contrasting functions and materials.

Shot blast cleaning

Shot blast cleaning, as expected, is a process used for cleaning. It is an ideal solution for cleaning steel and other ferrous metal surfaces. Aside from a cleaner aesthetic, shot blast cleaning will help to prepare the metal surface for painting or coating.

The process is undertaken using specialist equipment that shoots out rapid streams of an abrasive material. Shot blasting uses a variety of different abrasives, ranging from glass to plastic to aluminium oxide. These tiny abrasives are shot out at high force, slowly chipping away at the unclean surface layer to reveal a cleaner layer underneath.

Shot peening

Shot peening is another form of abrasive blasting, but unlike shot blast cleaning, shot peening is used to relieve residual stress. Residual stress can occur from a manufacturing error. If a metal cools unevenly during a casting process, for example, this can place higher levels of stress upon neighbouring parts. This can be problematic, as stress can compromise structural integrity. If not addressed quickly, cracks will likely start to form.

Shot peening is the method used to remedy this problem. Shot peening works similarly to shot blast cleaning by shooting rapid streams of tiny metal balls at a surface. The metal balls cause tiny indentations in the surface of the object, smoothing out the surface and relieving stress in the components. This process can be likened to getting a massage; force is used on a surface to relieve pressure in certain areas.

The difference

So what are the key differences?

Shot blasting and shot peening have different functions. One is to clean a surface — be it for aesthetic reasons or to provide a surface for effective painting — and the other is to relieve tension.

They also both use different materials. While metal can be used in shot blasting in some cases, you will often find a variety of other abrasives being used. In contrast, shot peening will always operate with metal abrasives.

Here at J Radford Group, we offer a wide range of shot blasting services for cleaning and repair purposes. Utilising a wide range of abrasives and cutting-edge equipment, we bring the highest quality operations to customers all throughout London. All our shot blasting is operated from within our soundproof tents, meaning you can enjoy our services completely noise-free. To enquire further, give our friendly team a call of use the contact us form today.