Kermetico HVAF AK5 Compact System for Spraying Metal, Alloy and Cermet Coatings
The Kermetico HVAF AK5 Compact System is used for Spraying Metal, Alloy and Cermet Coatings onto Thin Walls, Inside Diameters and Complex Geometries. As a member of Kermetico AK family, it works with the same AK control system.
The compact Kermetico HVAF AK5 system successfully deposits cermet and metal coatings onto internal diameters 200 mm (8”) or larger.
Two versions of the gun are available: the standard AK5 to be manipulated by a robot or other manipulator and a rotating AK5 gun to spray alloys and cermets onto inside diameters of fixed parts. The AK5 system prevents oxidation and decomposition of the feedstock and also keeps the air clean.
A Micrograph of a NiCrBSi Coating Applied by the Kermetico HVAF AK5 Gun
HVAF Process Description and Advantages
The Kermetico HVAF AK5 system deposits cermet, metal and alloyed powders, heated and accelerated by the combustion products of the air-fuel gas mixture.
When entering the gun, the compressed air cools the gun. Then the preheated air is used for mixing with the fuel for combustion.
The mixture of pre-heated compressed air and fuel gas flows into the combustion chamber through the orifices of a catalytic ceramic insert.
Initial ignition of the mixture results in the heating of the insert above the mixture’s auto-ignition temperature and the hot insert then continuously ignites the mixture.
The spray powder is injected axially into a wide combustion chamber, where the gas flow is very slow, less than 40 m/s (130 ft./sec.)
The long residence time and exposure to favorable heat transfer conditions at high gas pressure, allows the powder to heat efficiently in the chamber.
As an optional tool for accurate feedstock heating, a spray operator may inject controlled amounts of a high heat conductivity gas (hydrogen, helium).
Leaving the chamber, the powder is propelled into the nozzle of chosen length and configuration, where it is accelerated to a velocity that may be from 8,00 to over 1,000 m/s (2,600 to 3,300 ft./sec.), dependent on the chosen nozzle and combustion chamber pressure.
When impacting a substrate, the spray powder particles form a coating.
Blast & Spray
Each Kermetico AK HVAF gun can be used in blast and spray operations.
You can eliminate blasting and masking for blasting in a different booth. Just prepare a part for coating, blast it with any AK gun (it is extremely fast and uniform) and spray with the same gun, spending 10x less time for the blasting operation.
It is much faster and more accurate than manual blasting. Furthermore, using HVAF blasting for surface preparation reduces blast media consumption by 100-times compared to blasting with compressed air.
