Harper’s pusher furnaces and tunnel kilns are designed for processes requiring precise control of temperature and atmosphere, ideal for those with longer residence times that require exact control of the heat up rate of the product (temperature profile) and lower gas/solid reaction. Our focus is on systems that offer the greatest operating life, lowest operating cost, and highest efficiency for the manufacturing of advanced materials.
Our innovative design enhancements consider the delicate pressure control within the system to provide accurate direction of the atmosphere flow path in the kiln. This facilitates evacuation of volatiles and optimizes atmosphere uniformity. Additionally, Harper’s unique gas curtain technology provides zone-to-zone atmosphere definition under specific conditions. Our distinctive stripping chamber design provides optimal isolation of internal tunnel chamber environment from ambient as well as efficient purging of ambient atmosphere entrained within the load entering the furnace without the use of mechanical doors and seals.
Harper approaches the design of a conveyor furnace as a complete system, with the ability to incorporate advanced control systems, skid mounting, gas treatment and handling, turnkey installation and complete field commissioning. Field service can incorporate control instrumentation integration and programming as well as process engineering optimization and support.
Pusher Furnace Design Enhancements
- Advanced graphite pushers for high temperature applications incorporate strategic heating element placement to achieve optimal temperature uniformity and advanced insulation designs to reduce energy consumption
- Precise control of atmosphere dew point along the length of the furnace achieved through sophisticated gas distribution technology
- Optimized design for maintenance and replacement parts and minimization of field installation effort through modular construction
- Multiple independently controlled temperature zones (length and width)
Pusher Furnace Capabilities
- Temperatures to 2800°C
- Electrically heated or gas-, oil- or dual-fuel fired
- Controlled atmospheres including flammables gases, as well as multiple atmospheres
- Process gas circulating and conditioning systems
- Defined residence times and capacity
- Automatic material handling and return systems
- Advanced seal design
- Automatic feed loading and product unloading
Typical Pusher Furnace Applications
- Oxide Reduction
- Solid-solid reaction
- Gas-solid reaction
- Parts processing
- Materials ideal for Pusher Tunnel furnaces – Metal Oxides, Powders, Rare Earths, Technical Ceramics, Energy Device Materials, Nuclear Materials