Centrifugal atomizing metal powder making machine
Centrifugal atomizing metal powder making machine is an important machinery for manufacturing metal powder, which is playing more and more part because of the controllability of the size as well as the shape of the powder and its low production cost.
However, due to technical limitations, gas atomization and ultrasonic atomization are more commonly used in most countries at present.
The output of the gas atomization powder making method is relatively high, but it requires a large amount of inert gas to protect and atomize, so a large amount of inert gas is wasted in the production process, and the production cost is also increased a lot. The powder produced is also quite irregular, and the finished product efficiency is low.
The powder produced by ultrasonic atomization has high sphericity and narrow range, but the output is low. In some western developed countries, Centrifugal atomizing metal powder making machine has gradually replaced gas atomization and ultrasonic atomization. Centrifugal atomization will be a trend in metal powder making in the future. CDOCAST has mature technology in this field. This article will introduce the process of centrifugal atomization.
Configuration of Centrifugal atomizing metal powder making
For the whole process, you need the following devices.
| Process | Equipment structure configuration |
| Melting material | Melting system Induction melting furnace Electric control cabinet |
| Pulverizing | Control cabinet system Electrical control system Online temperature control system Motor control system Online oxygen measurement system Online PLC control display system (Brand: Siemens) |
| Centrifugal atomization system Small melting furnace Atomizing tank (material: SUS304) Atomization chamber cooling system Oxygen and nitrogen control system of atomization chamber Atomization high-speed motor (including high-speed motor and motor cooling system) Atomization chamber vacuum system Spinning disc |
|
| Screening | Screening system Feeder Screening machine control cabinet Rotary vibrating screen Ultrasonic connection controller |
| Packaging | Packaging system Vacuum inflatable packaging machine |
| Auxiliary equipment | Chiller |
| Dust remover |
Brief Introduction of Melting System and Atomization Process
Overview and usage:
This induction melting furnace is a frequency conversion device that converts three-phase power frequency current into single-phase intermediate frequency current, and generates eddy current loss through electromagnetic field induction to achieve the purpose of heating and melting. It is used for smelting, heating up and heat preservation of ferrous or non-ferrous metals and alloy materials such as steel, copper, aluminum, zinc, lead, etc, mainly in foundry smelting industry.
Performance characteristics:
1.The zero-voltage scan soft-start mode can be started or stopped at any time in any state without impact on the power supply;
2.Fast smelting, low production cost; low pollution, meeting environmental protection requirements;
3.It can be melted directly from the cold furnace;the solution can be completely emptied, and it is convenient to change the type of melting material;
4.It is flexible and convenient for power adjustment, which can be adjustedcontinuously and smoothly. The temperature is uniform and easy to control, the oxidation loss is small, and the metal composition is uniform;
5.The furnace shell adopts cast aluminum alloy structure, which occupies a small area; the furnace body is easy to tilt, and electric or manual tilting methods can be selected.
6.It can automatically adjust the matching of the load impedance, without adjusting the compensation capacitance, and always make the equipment run in a good working condition.
Main Parameter of 150kg Intermediate Frequency Melting Furnace for Your Reference
| Input voltage | 380V/3phases | Input power frequency | 50Hz |
| Rated output frequency | 0.8KHZ±20% | Rated output power | 100kw |
| Rated input current | 160A | Rated output voltage | 750V |
| Power transformer capacity | 120KVA | Rated capacity of electric furnace | 150kg |
| Temperature in the furnace | 700 ℃ | Melting rate | 150kg/h |
| Power consumption per ton (excluding heat preservation) | Molten aluminum 620kwh/t | Cooling circulating water flow | 15t/h |
| Cooling water pressure | 0.2MPa | Circulating water temperature | Inlet temperature 2-35℃, outlet water temperature 55℃ |
Product introduction and features
1.The control system adopts the integrated control of large-scale programmable logic array modules. The single board structure avoids the phenomenon that the equipment cannot be operated due to poor contact after multiple board connectors are used for a period of time.
2.The arithmetic processing of various signals and the execution of corresponding actions are carried out automatically according to the program. Use the digital control system to replace the functions to be completed by various relay control loops.
3.The equipment can be started with full loading and cold furnace, which the start success rate is 100%.
4.When the grid voltage fluctuates by 10%, the intermediate frequency output voltage fluctuates no more than ±1%.
5.The cross-sectional area of various internal copper connections is sufficient to reduce power loss.
6.Unique sweep frequency start method, with 100% start success rate.
7.A regulator with fast response characteristics.
8.A unique regulator is designed with a response time of less than 100mS, which is completely suitable for the medium frequency power supply to adapt to the requirements of rapid response in the case of sudden load changes.
9.The constant power output of the power supply can ensure high power factor.
10.The impedance regulator specially designed for the constant power of the power supply can detect the change of impedance, and send this change into the circuit for digital calculation, and automatically adjust the matching of the load impedance, so that the intermediate frequency power supply can achieve constant power output. At the same time, due to the impedance regulator’s use, the operating power factor of the whole set of equipment can reach 0.9 or more in the constant power section of workpiece heating, with perfect and reliable protection function.
11.This control circuit is equipped with various protection measures such as overcurrent, overvoltage, phase lack of incoming line, undervoltage of power supply, low cooling water pressure and high cooling water temperature. Ensure the sensitivity and reliability of various protection functions.
12.Advanced phase sequence self-recognition function.
13.Simple and convenient debugging and maintenance.
14.Most of the parameter settings in the control panel are automatically completed by the internal circuit of the control panel. The user needs to adjust only the parameter settings of a few potentiometers. Therefore, the control board has strong versatility and interchangeability, and the debugging and maintenance are simple and convenient.
Supply scope
Complete set of aluminum shell intermediate frequency furnace equipment configuration
| No. | Item |
| 1 | IF power supply cabinet |
| 2 | Rectifier thyristor |
| 3 | Inverter thyristor |
| 4 | Water-cooled reactor |
| 5 | Electro-magnetic universal circuit breaker |
| 6 | Power switch button |
| 7 | Compensation electric heating capacitor |
| 8 | Aluminum shell furnace body |
| 9 | Reducer and bracket |
| 10 | Tilting furnace control cabinet |
| 11 | Crucible forming mold |
| 12 | Water-cooled cable |
Other auxiliary products of intermediate frequency furnace
| No. | Item | Function and characteristics |
| 1 | Closed cooling tower | Used for cooling the intermediate frequency furnace; small footprint, direct use, no need to dig a pool, fully enclosed soft water circulation cooling, to prevent pipeline blockage caused by debris; avoid the scale of electrical components, which can greatly reduce the failure rate of the intermediate frequency furnace. Extend the service life of the equipment; |
| 2 | Stove switch (hydraulic) | Automatic switching between furnace bodies; no manual assembly and disassembly are required when switching furnaces, and the operation and use are faster and safer; |
| 3 | Intelligent control system | PLC programmable controller, HMI man-machine interface. It can realize automatic operation such as automatic temperature control of intermediate frequency furnace equipment, automatic oven, anti-burning furnace alarm, furnace liquid weighing, etc., which is safer and more convenient to use. |
| 4 | Furnace rectifier transformer | Special transformer for intermediate frequency furnace power supply; compared with ordinary power transformers, it has more stable operation, high impedance resistance, low harmonics, low grid pollution, and more power and energy saving. |
| 5 | Ladle | Furnace liquid container is used for pouring or transferring furnace liquid. |
| 6 | Electric furnace building machine | Electric furnace lining tools: reduce the labor intensity of workers; improve the quality of furnace construction and furnace life cycle. |
| 7 | Crucible for intermediate frequency furnace | Silicon carbide, clay graphite, white corundum crucible |
| 8 | Intermediate frequency furnace lining material | Cast iron, cast steel, molten copper, molten aluminum, induction furnace lining materials. |
Atomization Process：
The basic process of centrifugal atomization Metal powder making machineis that the molten metal from the melting device is guided to the center of the rotating disk through the guiding device. Due to the effect of inertia and centrifugal throwing, the molten metal is distributed in the radial direction and forms a thin liquid film on the rotating disk. When the liquid film reaches the edge of the rotating disk, it is atomized into droplets. These droplets are solidified to form powders, which can produce metal powders of various specifications with high roundness.
Centrifugal atomizing metal powder making machine
Aluminum powder parameters of Centrifugal atomizing metal powder making machine：
1. Powder raw material: metallic aluminum (the melting point of aluminum is 660.4℃, the boiling point of aluminum is 2407℃; the density of aluminum is 2.7×103kg/m3)
2. Furnace capacity: 100kg molten metal/furnace (in terms of the density of metal aluminum)
3. Capacity: 35±5kg/h
4. Powder particle size after atomization: +15-45 microns >60% 5. Powder oxygen content: <300 PPM
Main parts of the Centrifugal atomizing metal powder making machine:
1.The temperature control meter adopts Japanese brand.
2.The electrical switches, contactors, etc. adopt the French Schneider brand.
3. The high-speed motor adopts domestic brands
4. High-speed motor inverter adopts domestic brands
Centrifugal atomizing metal powder making machine acceptance method:
1. Use pure aluminum powder
2. Feeding amount per hour 35±5kg/h
3. Atomization rate +15-45 microns >60%
4. The oxygen content is less than 300 PPM. (Nitrogen purity is 99.999%)
5. The above particle size detection method is tested by Malvern laser particle size analyzer or test sieve method. One of the two passes the test and can be regarded as qualified.
Acceptance project of atomization process:
1. Whether the total amount of atomized powder per hour meets 35±5Kg/Hr.
2. Whether the atomization rate meets +15-45 microns of 60% or more.
3. Oxygen content of aluminum powder ﹤300 PPM
4. Spherical roundness of aluminum powder ﹥80%. (The spherical standard ratio is 1.5)
The purchaser of the above four items of acceptance can self-inspect to confirm whether it meets the standards. If there is any objection, both parties will jointly send samples to a nationally recognized testing agency for testing.
