Blasting and Spraying with Kermetico HVAF Equipment
When using a HVAF gun for grit blasting, grit particles are accelerated to extremely high velocity and simultaneously heated to over 1,200oC (2,200oF), dramatically improving cleaning and profiling efficiency of the process. Surface preparation by HVAF grit blasting increases production rate 5+ folds with reduction of grit consumption over 10-fold compared to conventional grit blasting with compressed air. Besides, the same setup is needed for blasting and coating spraying when using the same gun, what results in further cuts of time for thermal spray coating.
The standalone HVAF High-Pressure Hot Blasting Grit Feeder is designed to feed Kermetico HVAF guns with grit media.
The HVAF grit feeder includes:
- A set of 3 m (10’) hoses/cables and 4.5 m (15’) powder hose.
- Stand-alone manual control unit.
- A 3.5 litres powder canister.
Typical Specifications
| Power | 110 or 220 VAC, single phase |
| Typical Grit Used | Aluminium oxide, Silicon carbide, Tungsten carbide |
| Grit Particle Size | From #220 to #24 mesh |
| Grit Consumption | 1 – 8kg/hour |
| Canister Volume | 3.5L |
| Blasting Rate | 5 – 20m2/hour |
Safety of Blasting Operations
OSHA warns that workers involved with abrasive blasting may be exposed to dust and toxic metals, putting them at risk for lung damage.
Properly organized HVAF blasting is fully automated and free of any health hazards.
Surface Quality
The bond strength of a coating is critical for thermal spray applications. The bond strength is dependent on the type of coating material, substrate surface preparation and spray parameters.
While spray parameters are optimized carefully, most surface preparation is done by manual grit blasting, with little or no calibration of blast parameters and unpredictable operation cycle time and quality. Blasting is highly dependent on operator skill and often surface finish is only assessed visually, which means that a consistent, reproducible surface profile cannot be guaranteed. Moving a workpiece from a blasting room to the spray shop carries the risk of oxidation or contamination of the blasted surface.
HVAF hot grit blasting, in contrast, is fully automated and provides predictable, high-quality results.
The thermal spray coating is executed immediately after blasting, which minimizes the risk of oxidation.
Example Applications
HVAF Grit Blasting a Pump Case
HVAF Spraying a Tungsten Carbide Coating
HVAF Grit Blasting a Vessel
HVAF Grit Blasting a Roll
HVAF Grit Blasting a Ball Valve
HVAF Grit Blasting a Separator
Related HVAF Coating Information
For related HVAF coating information, view our Coating Material Selection page.
For more information on the equipment or consumables for HVAF Grit Blasting, call us on 07 3823 1004, or email us using our contact form.