In addition to the powder-feeder devices most commonly used in the thermal spray industry, gravity-based devices, rotating wheel devices, and fluidized-bed systems, other systems are currently in limited use or have been used in the past.
With vibratory powder-feed devices, the powder mass is vibrated and passes up a spiral channel that ends with the powder moving into the feed gas stream, as shown in the image. Such devices are commonly used in material transport systems. Their adoption to powder transportation for TS has been extensive in some service shops; however, these designs are not available for the general TS practitioner.
Image – Powder-feeding system: vibrating spiral feeder.
This information is from ASM Handbooks Online, Vol. 5A: Thermal Spray Technology, Coating Structures, Properties, and Materials. To find this information (subscription required), click on the link below and scroll down to Figure 19.
https://dl.asminternational.org/handbooks/edited-volume/12/chapter/133823/Feedstock-Material-Considerations-for-Thermal
