Uniquecoat® i5™
Internal Diameter HVAF Spray Gun
The i5 I.D. spray gun is designed for internal diameter applications, delivering high-performance cemented carbide, metal, and alloy coatings on internal diameters as small as 65 mm.
The i5 operates on propylene, and its highly efficient 100% air-cooling system eliminates the requirement for a chilled water supply.
The i5 internal-diameter spray gun delivers high-performance carbide, metal, and alloy coatings for internal surfaces.
● WC-based coatings with hardness up to 1200 HV300
● Variable nozzle configuration allows spraying internal diameters as small as 65 mm
● Coating porosity typically below 0.5%
● Compressive residual stresses in deposited coatings
● Negligible oxide content — typically only 1.5–2× higher than that of the feedstock material
● Durable, reliable operation with minimal maintenance requirements
Key Features:
● Axial powder injection – efficient, uniform particle heating and acceleration
● 100% air cooling – enables continuous operation without water or nitrogen cooling systems
● Continuous spraying capability – can spray for hours without interruption
● Low operating cost – optimized fuel and air consumption with minimal maintenance
● No oxygen required – safe, environmentally friendly HVAF combustion process
● Highest spray rate in class – delivers exceptional productivity and coating throughput
● Low spare part consumption – long-life nozzles and combustion components reduce cost of ownership
● Fast start-up – ready to spray within seconds for maximum uptime
Uniquecoat i5 I.D. HVAF Gun
Demo Videos of i5 HVAF Gun
i5 HVAF I.D. PROCESS DEMOSTRATION VIDEOS
Hot Grit Blasting and Carbide Coating of a 100 mm ID Tube
This video demonstrates hot grit blasting of a tube’s 100 mm inner diameter using the Uniquecoat i5 HVAF gun, followed by the application of a WC-10Co-4Cr coating. Hot grit blasting is a highly effective method for preparing internal surfaces, as few practical alternatives exist for ID surface preparation. Using fine grit (<100 µm) enables easy removal of abrasive particles with a compressed-air jet during blasting, preventing grit accumulation inside the tube.
Discharge of Powder Stream from the i5 HVAF Gun
This video shows the powder stream of a WC-based powder with a particle size of 2–10 µm exiting the nozzle of the Uniquecoat i5 HVAF gun at a powder feed rate of 5.1 kg/h. The footage clearly demonstrates a well-formed, symmetrical, and stable jet with no pulsation—an essential condition for achieving a high-quality, uniform coating.
Coating Microstructure
TYPICAL i5 COATING CROSS-SECTION MICROGRAPHS
Average Hardness 1110 HV0.3
Average Hardness 1110 HV0.3
Average Hardness 1203 HV0.3 Porosity: 0.03% via image analysis
Average Hardness 1203 HV0.3 Porosity: 0.03% via image analysis
Cross-sectional EDS (energy-dispersive X-ray spectroscopy) elemental mapping
No oxygen enrichment, no decarburization, and uniform W/Co/Cr distribution — all characteristic of a high-quality HVAF coating. The measured composition and morphology indicate minimal carbide decomposition, confirming low thermal input typical for HVAF vs. HVOF.