Pusher Furnace System | 0-1700ºC

INFORMATION

GENERAL

The MELLEN Pusher Furnace is designed for continuous operation, pushing plates around a rectangular work pattern. The plates are pushed across a stainless steel track along the front of the machine, during which time the processed product can be removed and new, unprocessed, material can be added. This allows for continuous batch style materials processing. The product then is pushed towards the back of the machine and inserted into the queue for the main pusher. Once in line with the main pusher, the product is pushed into the furnace.

Pusher furnaces are designed to push at a particular rate and can be designed as single or multi zone systems. Multi zone systems allow for the work to be processed under several different temperatures, and depending on the lengths of the zones, different times at temperature. Pusher furnaces allow for a multi-furnace, multi-step processes to be completed in one system.

MELLEN Pusher furnaces can be designed for a wide range of temperatures and hot zone dimensions. PF series furnaces can be designed for temperatures up to 1700ºC in air. There are several different grades of element that can be used in a Pusher furnace allowing the maximum temperature to be 1100ºC, 1250ºC, 1550ºC, or 1700ºC. Each system is custom designed to match your requirements.

Different maximum temperatures utilize different grades of heating elements to rapidly achieve the desired temperature while keeping the cost to a minimum. Each pusher furnace utilizes an energy efficient insulation package consisting of graded, ceramic fiber high-temperature insulation. There is a thermocouple port in the center of each zone for temperature measurements.

Pusher furnaces are designed to support adjustable rates as well as temperatures. The motion and temperature system is controlled using the ADAPT software. The motion system is all computer-controlled utilizing micro-stepping stepper motors and motor controllers. The push rates range from 0.1-inches per minute up to 5-inches per minute, and can be adjusted further by additional optional gear reducers.

HEATING ELEMENTS

Multiple wire types are used to ensure rapid and efficient heat control of the system at any temperature. Temperatures up to 1100ºC use nickel chrome alloy element wire, up to 1200ºC use iron chromium aluminum alloy, up to 1250ºC use APM wire, up to 1325ºC use heavy gauge iron chromium aluminum alloy, and temperatures up to 1450ºC use platinum wire.

Silicon Carbide heating elements are capable of 1550ºC in air. These elements operate with low surface-watt loading for longer life at elevated temperatures. They are strategically engineered to maximize element life without compromising uniformity of heating within the furnace.

Moly Disilicide heating elements are capable of 1700ºC in air. The heating elements are strategically located within the furnace chamber to maximize uniformity. The maximum temperature is dependent on the grade of the heating elements: Grade I at 1600ºC; Grade II at 1700ºC; Grade III at 1800ºC. The heating elements are field-replaceable for ease of maintenance and are precisely placed to radiate heat uniformly to the internal chamber.

Power requirements can vary based on temperature, diameter, and heated length of the furnace. Estimated power requirements will be provided during the quoting process.

CONTROLLER

Pusher furnaces are controlled using the ADAPT software. The power supply consists of the following major components: a customer specified digital temperature controller; a furnace-specific number of solid state relays or SCRs; appropriate circuit protection and safety interrupts for use in the elevator system; a MELLEN Control Cabinet to house all control system components; all necessary wiring, terminal boards, interconnections, etc. to create a completely operational system.

Still have questions? Please contact MELLEN’s engineers to learn more.