Rotating tube electric furnace for processing powder materials

The rotary tube electric furnace, with its design, achieves uniform heating and efficient processing when processing powder materials, and is widely used in multiple industrial fields. Let’s take a detailed look at the rotary tube electric furnace below!

Rotating tilted tube furnace with gas flow (click on the image to view product details)

1. Working principle and core advantages
Dynamic heating mechanism
The powder rotates with the rotating tube in a horizontal or inclined position, while being radiated by the heat source outside the tube and subjected to convective heat transfer by the airflow inside the tube. This dynamic motion causes the powder particles to continuously roll, avoiding local accumulation and ensuring uniform heat transfer, greatly improving the uniformity of sintering, melting and other processes.

Accurate control of temperature and atmosphere
Temperature uniformity: By using multi-point temperature control systems (such as fuzzy PID algorithm) and nanoscale thermal barrier coatings, the fluctuation of high temperature zones (such as 1700 ℃) is controlled within ± 5 ℃, meeting the requirements of high-precision material preparation.
Atmosphere flexibility: Supports vacuum (up to 10 ⁻ ³ Pa) and inert/oxidizing gas (such as nitrogen, argon, oxygen) environments to prevent powder oxidation or promote specific chemical reactions, suitable for oxygen free sintering of active materials (such as silicon carbide).

Efficient and energy-saving design
The double-layer furnace structure is filled with alumina and ceramic insulation to reduce heat loss, and the surface temperature is far below the safety limit.
High quality heating elements (such as silicon molybdenum rods) quickly heat up and stably output heat, shortening the processing cycle.

2. Key parameter control for powder processing
Rotation speed and inclination angle
The rotation speed (0-10rpm) and furnace inclination angle (such as 15 °) jointly regulate the flow state of the powder. For example, tilting rotation causes the powder to form a dynamic fluidized layer under the action of gravity and centrifugal force, avoiding the problem of uneven density in static sintering.
By adjusting the inclination angle, the powder retention time and discharge speed can be controlled to meet different process requirements.

Vacuum and Atmosphere System
The vacuum pump assembly (such as Roots pump+molecular pump) rapidly extracts air to maintain a high vacuum environment and prevent powder oxidation.
Gas flow meters and regulating valves precisely control the flow rate of inert/reducing gases to meet specific reaction conditions.

Temperature control strategy
Multi stage program temperature control (such as 30 stage programmable) supports a process flow of slow heating (excluding moisture/organic matter), high temperature insulation (promoting densification), and rapid cooling (preventing cracking).
The heating rate (0-20 ℃/min) and holding time are optimized according to the characteristics of the powder, for example, the heating rate of 5-20 ℃/min is commonly used for metal powder sintering.

3. Typical application areas
powder metallurgy
Metal powders (such as iron, copper, and titanium) are sintered and formed in a rotary tube furnace. By controlling temperature, vacuum degree, and rotation parameters, the density and mechanical properties of the products are improved, and they are widely used in the production of components in aerospace and automotive manufacturing.

Preparation of Ceramic Materials
High performance ceramics are prepared by high-temperature sintering of ceramic powders (such as zirconia and silicon nitride). The rotating motion promotes uniform grain growth, improves hardness, wear resistance, and high temperature resistance, and is used in fields such as electronic ceramics and structural ceramics.

Research and development of new energy materials
The positive and negative electrode materials of lithium-ion batteries, such as lithium cobalt oxide and graphite, are sintered in vacuum or inert atmosphere to optimize the crystal structure and improve charge and discharge efficiency and cycle life.
Fuel cell catalyst powder enhances catalytic performance by regulating the distribution of active components through atmosphere control.

Catalyst preparation
In the powder sintering process of hydrogenation catalysts in the petrochemical industry and waste gas treatment catalysts in the environmental protection field, the rotary tube furnace precisely controls the pore structure and specific surface area to enhance the activity and stability of the catalysts.

Rotating tube furnace commonly used for powder sintering (click on the image to view product details)

4. Equipment selection and operation suggestions
Key selection points
Temperature range: Select the highest temperature (such as 1200 ℃ or 1700 ℃) according to the powder processing requirements.
Furnace tube material: High purity corundum tubes are suitable for high-temperature oxidizing environments, while metal tubes (such as stainless steel) are suitable for reducing atmospheres.
Automation level: Prioritize equipment equipped with PLC control systems and remote operation functions to improve production efficiency.

Operation precautions
Preheating and cooling: Slowly raise the temperature to the target temperature to avoid thermal stress damage to the powder; Control the rate during the cooling phase to prevent material cracking.
Atmosphere switching: When switching between vacuum and gas atmospheres, ensure the sealing of the system to prevent air from entering and contaminating the powder.
Maintenance: Regularly clean the residual powder on the inner wall of the furnace tube, check the performance of the heating element and vacuum pump, and extend the service life of the equipment.Click to learn more Customized tube furnaces! Or click on online customer service to learn more about product information!