Wickens Shot Blasting Solutions

All our processes treat a material using external mechanical means – there is always an energy conversion at the surface. Propelling an abrasive media with hard sharp edges can remove material when it collides with the surface. Propelling a spherical media, fully rounded, can compress the surface material relieving stress, or redistributing it. If hard media is vibrated against a softer surface it can produce polishing or smoothing effects. And if softer rounder media is propelled at loose dirt, oil and other surface contaminants, it can produce cleaning effects without a change in the underlying appearance.

We accept that many people use these terms to mean the same thing yet there is a technical difference. Both involve accelerating small particles of relatively hard matter (like steel, glass and grit) to a high velocity, and aiming it at a less hard surface. To some, shot blasting is a process to remove loose surface contaminants, like rust or dirt. To others it means shot peening: the compression of an outer layer of surface material to make it resistant to fatigue and surface corrosion. In some cases, blast cleaning means removing a small layer of good material to give a subsequent coating or weld a better grip on the surface.

These are unlike processes applied to achieve different results. The only similarities are basic: each is a process of propelling media at a high velocity to strike a surface. Shot peening however requires control over a consistent size and shape of media, a consistent velocity of media, a consistent volume of media striking each surface area, and for a consistent length of time. Careful controls yield consistent and repeatable results that are not measurable visually. Blast cleaning is ordinarily less controlled, therefore less expensive, and results can usually be assessed visually.

The answer depends on the result desired, the surface hardness of the material being treated, and the aesthetics desired for the treated part. Wickens Industrial carries many varieties of media, in many sizes and hardness’s: steel shot, stainless (conditioned) cut wire shot, glass bead, aluminum oxide, plastic, baking soda, wheat starch, and of course dry ice (CO2).

Shot peening can be measured using expensive means (such as with X-ray analysis) both destructively and non-destructively. The most widely accepted, non-destructive, commercially acceptable measurement involves use of Almen methods. Wickens Industrial uses nothing but Electronics Inc. ® Almen products – very simply the best in the world. Other blast treatments are generally measured visually: most often as a result of testing and customer assessment. All treatments are carefully controlled and documented like a recipe, for reliable, consistent and repeatable results.

Airless treatments use centrifugal wheels from manufacturers like Bronco™, Goff®, Pangborn® and Wheelabrator™. Centrifugal wheels rotate much like a cooling fan with blades: allowing media placed at the centre of the wheel, to roll along each spinning “blade” gathering velocity. Once the media rolls off the end of the blade, it is moving at maximum velocity until the surface is struck: when impact occurs. This is an excellent method to “blast” lots of media in a short time, but in order to “roll”, the media must be round, or nearly so. Air-based systems use compressed air to accelerate each particle of media to the desired velocity. The media and air is directed using hoses and nozzles for aim. A single nozzle “blasts” less media than a single wheel. In both cases, blasting makes media travel in a straight line. If the surface has a complex shape, sometimes nozzles, used only with air, have to be used to aim at all required angles. To use media that is not generally round requires air-based systems. Similarly, low-mass media like dry ice must use air for propulsion. Wickens Industrial uses both systems in their surface treatment facility, allowing a flexible solution best suited to the customer requirement.

Experimentation. Where it has not been previously determined, reputable job shops can suggest a range of treatments that provide a range of results. Wickens Industrial in consultation with the customer will determine whether centrifugal wheels, direct pressure or suction-style nozzles will achieve the best results.

Wickens Industrial has provided surface preparation processes on ferrous metals, alloys, aluminums, stainless steels, sheet metals, spun metals, castings, wire forms, powdered metals, plastics, stampings, welds, and extrusions.

We know we have to provide value to our customers. They tell us we are competitively priced, turn jobs around quickly, and complete their jobs by the promised times. Our surface preparation shop is ISO 9000:2001 certified to assure consistent quality and service. We also know there are few competitors who offer blast cleaning, shot peening, mass finishing, in one-stop. Some of our customers have asked us to help with transition from job shop to in-house capability – a solution we are happy to provide.