GST Powder Feeder Hoppers for Thermal Spray Systems

Key benefits

• Multiple hopper capacities - 1.1 L, 1.5 L and 5 L - allow the powder inventory to be matched to spray duration, material value and changeover frequency.
• Universal variants are suitable for APS, HVOF-LF and HVOF-GF thermal spray processes, reducing the number of dedicated hopper types required in multi-process production.
• Transparent polycarbonate versions provide direct visual control of powder quantity and powder behaviour inside the hopper during setup and operation.
• Aluminium versions provide robust industrial construction and are available in heated configurations for applications requiring powder temperature conditioning.
• Integrated powder agitation helps maintain consistent powder movement and reduce settling or bridging.
• Servo drive with adjustable rotation setting from 0 to 100% in 1% increments supports controlled hopper operation within the powder feeding assembly.
• Universal configurations are designed for carrier-gas working pressure up to 12 atm, supporting demanding plasma and HVOF feeding conditions.
• The hopper family can be integrated into GST powder feeder systems and MP 3000 thermal spray platforms with single or multiple independent powder feed lines.

Typical Hopper Configurations

The following configurations reflect the product family used as the technical basis for this GST category. Final GST article numbers, interfaces and pressure ratings should be confirmed for each production version before publication or quotation.

Hopper Materials and Construction

Aluminium hoppers are intended for industrial installations where mechanical robustness and process versatility are priorities. Selected aluminium configurations can be equipped with powder heating, making them suitable for processes where the powder condition must be stabilized before and during feeding.

Transparent polycarbonate hoppers provide a clear view of the powder inventory. This is useful during material changeover, commissioning and process development because the operator can visually check powder level and observe whether the material is settling or moving inside the hopper. The referenced transparent configurations do not include powder heating.

Powder Agitation and Heating

Stable powder delivery begins with stable powder condition in the reservoir. The referenced hopper configurations include a powder mixing or agitation function. The assembly uses a servo drive with adjustable rotation control from 0 to 100% in 1% increments, allowing the operating setting to be matched to the powder and production task.

Heating is available on selected aluminium configurations. It can be used when powder conditioning is required before transport into the carrier-gas stream. Because powder behaviour varies with particle size distribution, morphology, density and moisture sensitivity, the need for heating and the appropriate agitation setting should be defined for the specific feedstock.

APS and HVOF Process Compatibility

Universal GST hopper configurations are intended for use with atmospheric plasma spray, liquid-fuel HVOF and gas-fuel HVOF powder feeding systems. Their 5-12 atm carrier-gas working-pressure range supports a broad selection of thermal spray process conditions. A dedicated transparent 1.5 L APS version is intended for lower-pressure APS operation at 5-6 atm.

The correct hopper should be selected together with the powder feeder because stable delivery depends not only on hopper volume, but also on the dosing mechanism, carrier-gas flow, powder hose arrangement, injector configuration and the physical properties of the coating material.

Integration with GST MP 3000 Powder Feeders

GST MP 3000 plasma and HVOF systems use a modular powder feeder in which coating powder is loaded into a dedicated hopper and transported to the spray gun or torch by carrier gas. The MP 3000 architecture can be configured with one to four independent powder feed lines, allowing several materials or process recipes to be prepared within the same thermal spray installation.

At system level, GST MP 3000 powder feeder configurations can include hopper quick-change capability, powder level monitoring, carrier-gas mass flow control and optional gravimetric powder-feed measurement. Hopper capacity can therefore be selected as part of the complete process architecture rather than as an isolated component.

How to Select a Powder Feeder Hopper

Hopper selection should be based on the spray process, expected powder consumption per cycle, number of coating materials, frequency of powder changeover and the characteristics of the powder itself. Smaller hoppers can reduce the amount of expensive powder held in the system and simplify frequent material changes, while 5 L versions are better suited to extended production cycles where higher powder inventory is beneficial.

For project selection, GST recommends confirming the thermal spray process, powder feeder model, required carrier-gas pressure, powder material and particle size range, expected feed rate, desired hopper volume, need for visual level inspection, and whether powder heating is required.

Applications

• Atmospheric plasma spray systems applying ceramic, metallic and composite powder coatings.
• HVOF-LF systems for dense wear- and corrosion-resistant coatings using liquid-fuel torches.
• HVOF-GF systems using gaseous fuel and high-pressure powder transport.
• Multi-material coating cells requiring two or more independent powder feed lines.
• Robotic and automated thermal spray production using GST MP 3000 process equipment.
• Process development and laboratory installations where transparent hoppers simplify visual observation and material changeover.
• Production applications requiring heated aluminium hoppers for controlled powder conditioning.